Aeroflex 2026 User Manual

MULTISOURCE GENERATOR
2026

Operating Manual

Document part no. 46892/439
Issue 3
6 April 2001
MULTISOURCE GENERATOR
2026
10 kHz to 2.4 GHz
Includes information on:
Option 1 − Three internal signal sources. Option 3 − High-stability frequency standard. Option 4 − Rear-panel connections.
This manual applies to instruments with software issues of 10.00 and higher.
© IFR Ltd. 2007
No part of this book may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, or recorded by any information storage or retrieval system, without permission in writing by IFR Ltd.
Printed in the UK
Manual part no. 46892/439
Issue 3
6 April 2001
i
This manual explains how to use the 2026 Multisource Generator.

Intended audience

Persons who have a need for accurately generated signals in the VHF and UHF spectrum. It is assumed that the reader will be familiar with telecommunication terms used in modern
communication systems.

Structure

Chapter 1 Main features and performance data Chapter 2 Installation details Chapter 3 Local operation Chapter 4 Source configuration, coupling and selected applications Chapter 5 GPIB operation with keywords and sample programs Chapter 6 Brief technical description Chapter 7 Instructions for doing acceptance testing
About this manual

Document conventions

The following conventions apply throughout this manual: RF OUTPUT Titles marked on the instrument panel are shown in capital letters.
[SET UP] Key titles are as shown on the key-caps in square brackets. [Carrier Freq] Soft key titles are shown in italics in square brackets; for example, [Carrier Freq]
means the soft key adjacent to the Carrier Freq title box at the side of the menu.
RF Level Messages on the display are shown in italic letters.

Associated publications

Other publications covering specific aspects of this equipment are:
Maintenance Manual (46882/295) Covers maintenance and repair. Service Manual (46880/094) Consists of operating manual (this document) plus
maintenance manual.
ii 46882/439
Contents
PREFACE ...................................................................................................................................................... iv
Precautions ....................................................................................................................................................... v
Précautions ....................................................................................................................................................viii
Vorsichtsmaßnahmen Precauz
Precauciones ....................................................................................................................................................xiv
ioni .....................................................................................................................................................xii
......................................................................................................................................... x
Chapter 1 GENERAL INFORMATION
Chapter 2 INSTALLATION .....................................................................................................................2-1
Chapter 3 LOCAL OPERATION.............................................................................................................3-1
First-time use............................................................................................................................3-9
Individual source operation...................................................................................................3-17
Sweep.......................................................................................................................................3-27
Utilities.....................................................................................................................................3-31
Memory...................................................................................................................................3-45
Error messages .......................................................................................................................3-49
Chapter 4 SETUP.......................................................................................................................................4-1
Combiner setup ........................................................................................................................4-3
Coupling....................................................................................................................................4-5
Applications ..............................................................................................................................4-7
Chapter 5 REMOTE OPERATION.........................................................................................................5-1
Chapter 6 BRIEF TECHNICAL DESCRIPTION..................................................................................6-1
Chapter 7 ACCEPTANCE TESTING .....................................................................................................7-1
Test procedures.........................................................................................................................7-5
Acceptance test results tables................................................................................................7-31
.................................................................................................1-1
INDEX .................................................................................................................................................... I-1
46882/439 iii

PATENT PROTECTION

The 2026 Multisource Generator is protected by the following patents: EP 0322139 GB 2214012 US 4870384 EP 0125790 GB 2140232 US 4609881

PREFACE

iv 46882/439

Precautions

These terms have specific meanings in this manual:
WARNING
information to prevent personal injury.
information to prevent damage to the equipment.
important general information.
Hazard symbols
The meaning of hazard symbols appearing on the equipment is as follows:
Symbol Description
General hazard Toxic hazard
General conditions of use
This product is designed and tested to comply with the requirements of IEC/EN61010-1 ‘Safety requirements for electrical equipment for measurement, control and laboratory use’, for Class 1 portable equipment and is for use in a pollution degree 2 environment. The equipment is designed to operate from an installation category 2 supply.
Equipment should be protected from the ingress of liquids and precipitation such as rain, snow, etc. When moving the instrument from a cold to a hot environment, it is important to allow the temperature of the instrument to stabilize before it is connected to the supply to avoid condensation forming. The instrument must only be operated within the environmental conditions specified in Chapter 1 ‘Performance data’ in the Operating Manual otherwise the protection provided by the equipment may be impaired.
This product is not approved for use in hazardous atmospheres or medical applications. If the equipment is to be used in a safety-related application, e.g. avionics or military applications, the suitability of the product must be assessed and approved for use by a competent person.
WARNING
Electrical hazards (AC supply voltage)
This equipment conforms with IEC Safety Class I, meaning that it is provided with a protective grounding lead. To maintain this protection the supply lead must always be connected to the source of supply via a socket with a grounded contact.
Be aware that the supply filter contains capacitors that may remain charged after the equipment is disconnected from the supply. Although the stored energy is within the approved safety requirements, a slight shock may be felt if the plug pins are touched immediately after removal.
Do not remove covers, no user serviceable parts inside. See list of IFR Ltd International Service Centers at rear of manual.
Fuses
Note that the internal supply fuse is in series with the live conductor of the supply lead. If connection is made to a 2-pin unpolarized supply socket, it is possible for the fuse to become transposed to the neutral conductor, in which case, parts of the equipment could remain at supply potential even after the fuse has ruptured.
46882/439 v
PRECAUTIONS
WARNING
Fire hazard
WARNING
Toxic hazards
WARNING
Beryllia
WARNING
Make sure that only fuses of the correct rating and type are used for replacement. If an integrally fused plug is used on the supply lead, ensure that the fuse rating is commensurate
with the with current requirements of this equipment. See under 'Performance Data' in Chapter 1 for power requirements.
Some of the components used in this equipment may include resins and other materials which give off toxic fumes if incinerated. Take appropriate precautions, therefore, in the disposal of these items.
Beryllia (beryllium oxide) is used in the construction of some of the components in this equipment. This material, if incorrectly handled, could cause a danger to health refer to the Maintenance part of the Service Manual for safe handling precautions.
Beryllium copper
WARNING
Heavy instrument
WARNING
Tilt facility
Some mechanical components within this instrument are manufactured from beryllium copper. This is an alloy with a beryllium content of approximately 5%. It represents no risk in normal use.
The material should not be machined, welded or subjected to any process where heat is involved. It must be disposed of as “special waste”. It must NOT be disposed of by incineration.
The weight of this instrument exceeds the 18 kg (40 lb) guideline for manual handling by a single person. To avoid the risk of injury, an assessment should be carried out prior to handling which takes account of the load, workplace environment and individual capability, in accordance with European Directive 90/269/EEC and associated National Regulations.
When the instrument is in the tilt position, it is advisable, for stability reaso ns, not to stack other instruments on top of it.
Static sensitive components
This equipment contains static sensitive components which may be damaged by handling refer to the Maintenance Manual for handling precautions.
vi 46882/439
Suitability for use
This equipment has been designed and manufactured by IFR Ltd. to provide RF signals from two or three configurable sources. IFR Ltd. has no control over the use of this equipment and cannot be held responsible for events arising from its use other than for its intended purpose.
PRECAUTIONS
46882/439 vii
PRECAUTIONS

Précautions

Les termes suivants ont, dans ce manuel, des significations particulières:
WARNING
contient des informations pour éviter toute blessure au personnel.
contient des informations pour éviter les dommages aux équipements.
contient d'importantes informations d'ordre général.
Symboles signalant un risque
La signification des symboles liés à cet équipement est la suivante:
Symbole Nature du risque
Risques généraux
Danger produits toxiques
Conditions générales d’utilisation
Ce produit a été conçu et testé pour être conforme aux exigences des normes CEI/EN61010-1 “Règles de sécurité pour appareils électriques de mesurage, de régulation et de laboratoire”, pour des équipements Classe I portables et pour une utilisation dans un environnement de pollution de niveau 2. Cet équipement est conçu pour fonctionner à partir d’une alimentation de catégorie II.
Cet équipement doit être protégé de l’introduction de liquides ainsi que des précipitations d’eau, de neige, etc... Lorsqu’on transporte cet équipement d’un environnement chaud vers un environnement froid, il est important de laisser l’équipement se stabiliser en température avant de le connecter à une alimentation afin d’éviter toute formation de condensation. L’doit être utilisé uniquement dans les conditions d’environnement spécifiées dans “Performance data” dans le chapitre 1 du manuel d’utilisation, toute autre utilisation peut endommager les systèmes de protection.
Ce produit n’est pas garanti pour fonctionner dans des atmosphères dangereuses ou pour un usage médical. Si l'équipement doit être utilisé pour des applications en relation avec la sécurité, par exemple des applications militaires ou aéronautiques, la compatibilité du produit doit être établie et approuvée par une personne compétente.
WARNING
!
Securite electrique (tension d'alimentation alternative)
Cet appareil est protégé conformément à la norme CEI de sécurité class 1, c'est-à-dire que sa prise secteur comporte un fil de protection à la terre. Pour maintenir cette protection, le cable d'alimentation doit toujours être branché à la source d'alimentation par l'intermédiaire d'une prise comportant une borne terre.
Notez que les filtres d'alimentation contiennent des condensateurs qui peuvent encore être chargés lorsque l'appareil est débranché. Bien que l'énergie contenue soit conforme aux exigences de sécurité, il est possible de ressentir un léger choc si l'on touche les bornes sitôt après débranchement.
Ne pas enlever les capots, aucune pièce réparable ne se trouve à l'intérieur. Contacter un des Centres de Maintenance Internationaux de IFR Ltd dans la liste jointe à la fin du manuel.
Fusibles
Notez que le fusible d’alimentation interne est en série avec la phase du câble d’alimentation. Si la prise d’alimentation comporte deux bornes non polarisées, il est possible de connecter le fusible au neutre. Dans ce cas, certaines parties de l’appareil peuvent rester à un certain potentiel même après coupure du fusible.
viii 46882/439
PRECAUTIONS
WARNING
Risque lie au feu
WARNING
Danger produits toxiques
WARNING
Le Beryllia
Lors du remplacement des fusibles vérifiez l'exactitude de leur type et de leur valeur. Si le cable d'alimentation comporte une prise avec fusible intégré, assurez vous que sa valeur est
compatible avec les besoins en courant de l'appareil. Pour la consommation, reportez-vous au chapitre 1 "Spécifications".
Certains composants utilisés dans cet appareil peuvent contenir des résines et d'autres matières qui dégagent des fumées toxiques lors de leur incinération. Les précautions d'usages doivent donc être prises lorsqu'on se débarrasse de ce type de composant.
Le Beryllia (oxyde de Beryllium) entre dans la composition de certains composants de cet appareil. Cette matière peut représenter un danger pour la santé s'il elle n'est pas manipulée de façon correcte se référer à la partie "Maintenance" du "Manuel de Maintenance" pour les précautions de manipulation.
WARNING
Bronze au béryllium
WARNING
WARNING
Dans cet équipement,certaines pièces mécaniques sont à base de bronze au béryllium. Il s'agit d'un alliage dans lequel le pourcentage de béryllium ne dépasse pas 5%. Il ne présente aucun danger en utilisation normale.
Toutefois, cet alliage ne doit pas être travaillé, soudé ou soumis à un processus qui implique l'utilisation d'une source de chaleur.
En cas de destruction, il sera entreposé dans un container spécial. IL ne devra pas être détruit par incinération.
Instrument lourd
Le poids de cet appareil est supérieur à la limite de 18 kg (40 lb), fixée pour le transport par une seule personne. Afin d’éviter tout risque de blessure, il est nécessaire de faire, avant le transport, une évaluation de la charge, des contraintes de l’environnement et des capacités de l’individu, en conformité avec la Directive Européenne 90/269/EEC ainsi que les recommandations Nationales concernées.
Position inclinée
Lorsque l'appareil est dans une position inclinée, il est recommandé, pour des raisons des stabilité, de ne pas y empiler d'autres appareils.
46882/439 ix
PRECAUTIONS

Vorsichtsmaßnahmen

Diese Hinweise haben eine bestimmte Bedeutung in diesem Handbuch:
WARNING
dienen zur Vermeidung von Verletzungsrisiken.
dienen dem Schutz der Geräte.
enthalten wichtige Informationen.
Gefahrensymbole
Die Gefahrensymbole auf den Geräten sind wie folgt:
Symbol Gefahrenart
Allgemeine Gefahr Warnung vor giftigen Substanzen
Allgemeine Hinweise zur Verwendung
Dieses Produkt wurde entsprechend den Anforderungen von IEC/EN61010-1 “Sicherheitsanforderungen für elektrische Ausrüstung für Meßaufgaben, Steuerung und Laborbedarf”, Klasse I, transportabel zur Verwendung in einer Grad 2 verunreinigten Umgebung, entwickelt und getestet. Dieses Gerät ist für Netzversorgung Klasse II zugelassen.
Das Gerät sollte vor dem Eindringen von Flüssigkeiten sowie vor Regen, Schnee etc. geschützt werden. Bei Standortänderung von kalter in wärmere Umgebung sollte das Gerät wegen der Kondensation erst nach Anpassung an die wärmere Umgebung mit dem Netz verbunden werden. Das Gerät darf nur in Umgebungsbedingungen wie in Kapitel 1 “Leistungsdaten (Performance data)” der Bedienungsanleitung beschrieben, betrieben werden; ansonsten wird der vom Gerät vorgesehene Schutz des Anwenders beeinträchtigt.
Dieses Produkt ist nicht für den Einsatz in gefährlicher Umgebung (z.B. Ex-Bereich) und für medizinische Anwendungen geprüft. Sollte das Gerät für den Einsatz in sicherheitsrelevanten Anwendungen wie z.B. im Flugverkehr oder bei militaerischen Anwendungen vorgesehen sein, so ist dieser von einer für diesen Bereich zuständigen Person zu beurteilen und genehmigen.
WARNING
!
Elektrische Schläge (Wechselspannungsversorgung)
Das Gerät entspricht IEC Sicherheitsklasse 1 mit einem Schutzleiter nach Erde. Das Netzkabel muß stets an eine Steckdose mit Erdkontakt angeschlossen werden.
Filterkondensatoren in der internen Spannungsversorgung können auch nach Unterbrechung der Spannungszuführung noch geladen sein. Obwohl die darin gespeicherte Energie innerhalb der Sicherheitsmargen liegt, kann ein leichter Spannungsschlag bei Berührung kurz nach der Unterbrechung erfolgen.
Entfernen Sie keine Gehäuseabdeckungen, es befinden sich keine austauschbaren Teile im Gerät. Eine Liste der IFR Servicestellen finden Sie auf der Rückseite des Handbuches.
Sicherungen
Die interne Sicherung in der Spannungszuführung ist in Reihe mit der spannungsführenden Zuleitung geschaltet. Bei Verbindung mit einer zweiadrigen, nicht gepolten Steckdose kann die Sicherung in der Masseleitung liegen, so daß auch bei geschmolzener Sicherung Geräteteile immer noch auf Spannungspotential sind.
x 46882/439
PRECAUTIONS
WARNING
Feuergefahr
WARNING
Warnung vor giftigen Substanzen
WARNING
Beryllium Oxid
WARNING
Es dürfen nur Ersatzsicherungen vom gleichen Typ mit den korrekten Spezifikationen entsprechend der Stromaufnahme des Gerätes verwendet werden. Siehe hierzu die Leistungsdaten (Performance Data) in Kapitel 1.
In einigen Bauelementen dieses Geräts können Epoxyharze oder andere Materialien enthalten sein, die im Brandfall giftige Gase erzeugen. Bei der Entsorgung müssen deshalb entsprechende Vorsichtsmaßnahmen getroffen werden.
Beryllium Oxid wird in einigen Bauelementen verwendet. Bei inkorrekter Handhabung kann dieses Material Gesundheitsschäden verursachen. Siehe hierzu
die Hinweise zur Handhabung im Service-Handbuch.
Beryllium Kupfer
In diesem Gerät sind einige mechanische Komponenten aus Berylium Kupfer gefertigt. Dies ist eine Verbindung welche aus einem Berylliumanteil von ca. 5 % besteht. Bei normaler Verwendung besteht kein Gesundheitsrisiko.
Das Metall darf nicht bearbeitet, geschweißt oder sonstiger Wärmebehandlung ausgesetzt werden. Es muß als Sondermüll entsorgt werden. Es darf nicht durch Verbrennung entsorgt werden.
WARNING
WARNING
Schweres Gerät
Das Gewicht dieses Geräts liegt über der 18 kg (40 lb) Grenze für Transport durch eine einzelne Person. Zur Vermeidung von Verletzungen sollten vor einem Transport die Arbeitsumgebung und die persönlichen Möglichkeiten im Verhältnis zur Last abgewogen werden, wie in der EU­Regelung 90/269/EEC und nationalen Normen beschrieben.
Schrägstellung
Bei Schrägstellung des Geräts sollten aus Stabilitätsgründen keine anderen Geräte darauf gestellt werden.
46882/439 xi
PRECAUTIONS

Precauzioni

Questi termini vengono utilizzati in questo manuale con significati specifici:
WARNING
riportano informazioni atte ad evitare possibili pericoli alla persona.
riportano informazioni per evitare possibili pericoli all'apparecchiatura.
riportano importanti informazioni di carattere generale.
Simboli di pericolo
Significato dei simboli di pericolo utilizzati nell'apparato:
Simbolo Tipo di pericolo
Pericolo generico
Pericolo sostanze tossiche
Condizioni generali d'uso.
Questo prodotto è stato progettato e collaudato per rispondere ai requisiti della direttiva IEC/EN61010-1 'Safety requirements for electrical equipment for measurement, control and laboratory use' per apparati di classe I portatili e per l'uso in un ambiente inquinato di grado 2. L'apparato è stato progettato per essere alimentato da un alimentatore di categoria II.
Lo strumento deve essere protetto dal possibile ingresso di liquidi quali, ad es., acqua, pioggia, neve, ecc. Qualora lo strumento venga portato da un ambiente freddo ad uno caldo, è importante lasciare che la temperatura all'interno dello strumento si stabilizzi prima di alimentarlo per evitare formazione di condense. Lo strumento deve essere utilizzato esclusivamente nelle condizioni ambientali descritte nel capitolo 1 'Performance Data' del manuale operativo, in caso contrario le protezioni previste nello strumento potrebbero risultare non sufficienti.
Questo prodotto non è stato approvato per essere usato in ambienti pericolosi o applicazioni medicali. Se lo strumento deve essere usato per applicazioni particolari collegate alla sicurezza (per esempio applicazioni militari o avioniche),occorre che una persona o un istituto competente ne certifichi l'uso.
WARNING
!
Pericoli da elettricità (alimentazione c.a.)
Quest' apparato è provvisto del collegamento di protezione di terra e rispetta le norme di sicurezza IEC, classe 1. Per mantenere questa protezione è necessario che il cavo, la spina e la presa d'alimentazione siano tutti provvisti di terra.
Il circuito d'alimentazione contiene dei filtri i cui condensatori possono restare carichi anche dopo aver rimosso l'alimentazione. Sebbene l'energia immagazzinata è entro i limiti di sicurezza, purtuttavia una leggera scossa può essere avvertita toccando i capi della spina subito dopo averla rimossa.
Non rimuovere i coperchi, utilizzare solo parti di scorta originali. Vedi elenco internazionale dei Centri di Assistenza in fondo al manuale.
Fusibili
Notare che un fusibile è posto sul filo caldo del cavo di alimentazione. Qualora l’alimentazione avvenga tramite due poli non polarizzati, è possibile che il fusibile vada a protezione del neutro per cui anche in caso di una sua rottura, l’apparato potrebbe restare sotto tensione.
xii 46882/439
PRECAUTIONS
WARNING
Pericolo d'incendio
WARNING
Pericolo sostanze tossiche
WARNING
Berillio
Assicurarsi che, in caso di sostituzione, vengano utilizzati solo fusibili della portata e del tipo prescritto.
Se viene usata una spina con fusibili, assicurarsi che questi siano di portata adeguata coi requisiti di alimentazione richiesti dallo strumento. Tali requisiti sono riportati nel cap. 1 "Performance data".
Alcuni dei componenti usati in questo strumento possono contenere resine o altri materiali che, se bruciati, possono emettere fumi tossici. Prendere quindi le opportune precauzioni nell'uso di tali parti.
Berillio (ossido di berillio) è utilizzato nella costruzione di alcuni componenti di quest'apparato. Questo materiale, se maneggiato non correttamente, può causare danni alla salute. Far riferimento
ai capitoli di manutenzione del Manuale di Servizio per le precauzioni richieste.
WARNING
Rame berillio
WARNING
WARNING
Alcuni componenti meccanici in questo strumento sono realizzati in rame berillio. Si tratta di una lega con contenuto di berillio di circa il 5%, che non presenta alcun rischio in usi normali.
Questo materiale non deve essere lavorato, saldato o subire qualsiasi processo che coinvolge alte temperature.
Deve essere eliminato come "rifiuto speciale". Non deve essere eliminato tramite "inceneritore".
Strumento pesante
Il peso di questo strumento supera i 18 kg (40 lb) raccomandati come limite per il trasporto manuale da parte di singola persona. Per evitare rischi di danni fisici è bene quindi considerare il carico complessivo, le condizioni del trasporto e le capacità individuali in accordo con la direttiva comunitaria 90/269/EEC e con eventuali regolamenti locali.
Posizionamento inclinato
Quando lo strumento è in posizione inclinata è raccomandato, per motivi di stabilità, non sovrapporre altri strumenti.
46882/439 xiii
PRECAUTIONS

Precauciones

Estos términos tienen significados específicos en este manual:
WARNING
contienen información referente a prevención de daños personales. contienen información referente a prevención de daños en equipos. contienen información general importante.
Símbolos de peligro
Los significados de los símbolos de peligro que aparecen en los equipos son los siguientes:
Símbolo Naturaleza del peligro
Peligro general
Aviso de toxicidad
Condiciones generales de uso
Este producto ha sido diseñado y probado para cumplir los requerimientos de la normativa IEC/EN61010-1 "Requerimientos de la normativa para equipos eléctricos de medida, control y uso en laboratorio", para equipos clase II portátiles y para uso en un ambiente con un grado de contaminación 2. El equipo ha sido diseñado para funcionar sobre una instalación de alimentación de categorías II.
Debe protegerse el equipo de la entrada de líquidos y precipitaciones como nieve, lluvia, etc. Cuando se traslada el equipo de entorno frío a un entorno caliente, es importante aguardar la estabilización el equipo para evitar la condensación. Sólo debe utilizarse el aparato en las condiciones ambientales especificadas en el capítulo 1 "Especificaciones" o "Performance Data" del Manual de Operación/Funcionamiento, en caso contrario la propia protección del equipo puede resultar dañada.
Este producto no ha sido aprobado para su utilización en entornos peligrosos o en aplicaciones médicas. Si se va a utilizar el equipo en una aplicación con implicaciones en cuanto a seguridad, como por ejemplo aplicaciones de aviónica o militares, es preciso que un experto competente en materia de seguridad apruebe su uso.
WARNING
!
Nivel peligroso de electricidad (tensión de red)
Este equipo cumple las normas IEC Seguridad Clase 1, lo que significa que va provisto de un cable de protección de masa. Para mantener esta protección, el cable de alimentación de red debe de conectarse siempre a una clavija con terminal de masa.
Tenga en cuenta que el filtro de red contiene condensadores que pueden almacenar carga una vez desconectado el equipo. Aunque la energía almacenada está dentro de los requisitos de seguridad, pudiera sentirse una ligera descarga al tocar la clavija de alimentación inmediatamente después de su desconexión de red.
No quitar las tapas, en el interior no existen piezas reemplazables por el usuario. Vea la lista de Centros de Servicios Internacionales en la parte trasera del manual.
Fusibles
Se hace notar que el fusible de alimentación interno está enserie con el activo del cable de alimentación a red. Si la clavija de alimentación de red cuenta con sólo dos terminales sin polaridad, el fusible puede pasar a estar en serie con el neutro, en cuyo caso existen partes del equipo que permanecerían a tensión de red incluso después de que el fusible haya fundido.
xiv 46882/439
PRECAUTIONS
WARNING
Peligro de incendio
WARNING
Aviso de toxicidad
WARNING
Berilio
Asegúrese de utilizar sólo fusibles del tipo y valores especificados como recuesto. Si se utiliza una clavija con fusible incorporado, aseg úrese de que los valores del fusible
corresponden a los requeridos por el equipo. Ver sección de especificaciones del capítulo 1 para comprobar los requisitos de alimentación.
Alguno de los componentes utilizados en este equipo pudieran incluir resinas u otro tipo de materiales que al arder produjeran sustancias tóxicas, Por tanto, tome las debidas precauciones en la manipulación de esas piezas.
Berilio (óxido de berilio) Este material es utilizado en la fabricación de alguno de los componentes de este equipo.
Si se manipulase incorrectamente podria causar daños a la salud En la sección de mantenimiento y reparación encontrará normas de manejo de seguridad.
WARNING
Berilio-cobre
WARNING
Instrumento pesado
WARNING
Tener en cuenta con el equipo Inclinado
Algunos componentes mecánicos contenidos en este instrumento incorporan berilio-cobre en su proceso de fabricación. Se trata de una aleación con un contenido aproximado de berilio del 5%, lo que no representa ningún riesgo durante su uso normal.
El material no debe ser manipulado, soldado, ni sometido a ningún proceso que implique la aplicación de calor.
Para su eliminación debe tratarse como un "residuo especial". El material NO DEBE eliminarse mediante incineración.
El peso de este instrumento excede de los 18 kg (40 lb), lo que debe tenerse en cuenta si va ser transportado manualmente por una sola persona. Para evitar el riesgo de lesiones, antes de mover el equipo deberá evaluar la carga, el entorno de trabajo y la propia capacidad, de acuerdo con la Directiva Europea 90/269/EEC y el Reglamento Nacional Asociado.
Si utiliza el equipo en posición inclinada, se recomienda, por razones de estabilidad, no apilar otros equipos encima de él.
46882/439 xv
Contents
Chapter 1

GENERAL INFORMATION

Introduction....................................................................................................................................1-1
Main features .................................................................................................................................1-2
Operation Display Frequency selection Output
odulation..............................................................................................................................1-2
M Increm Frequency sweep Mem Program Calibration data Spectral purity
Calibration Perform Versions, options and accessories
................................................................................................................................1-2
....................................................................................................................................1-2
................................................................................................................1-2
.....................................................................................................................................1-2
enting...........................................................................................................................1-3
....................................................................................................................1-3
ory...................................................................................................................................1-3
ming ..........................................................................................................................1-3
.......................................................................................................................1-3
.........................................................................................................................1-3
..............................................................................................................................1-3
ance data ...........................................................................................................................1-4
..................................................................................................1-9

Introduction

The 2026 is a multisource signal generator offering as standard two signal sources in one instrument. Up to three sources may be fitted, each of which is a fully functional modulated signal generator. Each source can either be routed to its own individual RF output or switched to the input of an RF combiner network before being fed to a separate combined RF output. All sources cover the frequency range 10 kHz to 2.4 GHz. An additional RF input is provided to enable the output from an external RF signal generator to be combined with the signals from up to two internal sources.
Each signal source can be controlled independently in frequency and level, and each has its own amplitude, frequency, phase, FSK and pulse modulation capability. All parameters can be entered from the front-panel keyboard and a rotary control can be used to adjust most settings. The instrument includes a GPIB interface which allows remote control of all standard signal generator functions except the supply switch.
The instrument is provided with built-in tests specifically for use with two or three combined sources such as for amplifier and receiver intermodulation tests and receiver selectivity tests. The sources may be locked together, offset in frequency (additionally with a harmonic or sub-harmonic relationship) as well as level.
Microprocessor control ensures that the instrument is flexible and easy to use and allows programming by the General Purpose Interface Bus (GPIB) or RS-232 serial bus. The GPIB is designed to IEEE Standard 488.2 and is a means of sending commands to an instrument, via a data bus, from a remote controller or personal computer. The instrument can therefore be used manually or as part of a fully automated test system.
46882/439 1-1
GENERAL INFORMATION

Main features

Operation

Selection of parameters on the screen may involve one or more of the numeric, hard or menu selection keys or the rotary control knob. Parameters may be set to specific values by numeric key
entry, while values may be varied in steps of any size using the [ moving the control knob, set to a particular sensitivity.

Display

The display is a dot matrix liquid crystal panel, with backlighting. Display contrast and brightness may be varied to accommodate differing lighting conditions and the setting saved in memory.

Frequency selection

Carrier frequency is either selected directly via the keyboard or remotely via the interfaces. Frequency resolution is 1 Hz across the complete frequency range of 10 kHz to 2.4 GHz. A series of carrier frequencies can be stored in non-volatile memory for recall when required.

Output

Peak RF output levels from each signal source of up to +24 dBm can be set up to 1.2 GHz (+20 dBm up to 2.4 GHz) by direct keyboard entry with a resolution of 0.1 dB down to
137 dBm. The peak output level from the combiner is +4 dBm up to 1.2 GHz (0 dBm up to
2.4 GHz). RF ON/OFF keys are provided to disable each individual output as well as the combined output.
A choice of level units is available to the user and provision is made for the conversion of units (for example, dBm to μV) by a simple keypress.
An electronic trip protects each independent signal source output against reverse power of up to 50 W. This prevents damage to output circuits when RF transmitter or DC power supply is accidentally applied to an RF OUTPUT connector.
To facilitate testing of receiver squelch systems, an attenuator hold function allows control of the RF output without introducing RF level drop-outs from the step attenuator.
Ø][×] keys or altered by

Modulation

Comprehensive amplitude, frequency and phase modulations are available. Pulse modulation can be applied to the carrier from an external pulse source. The instrument also produces FSK modulated outputs. An internal modulation oscillator is provided, having a frequency range of
0.01 Hz to 20 kHz. Sine, triangle and square waveforms are available. The oscillator is capable of generating one or two modulation tones simultaneously in one modulation channel. A BNC connector on the front panel offers access to the internal LF signal as well as providing an input for external modulation signals to be combined with the internal signals. These sources can be combined to give a number of modulation modes. The pulse modulation can be used in combination with the other forms of modulation.
The frequency modulation range provides a 1 dB bandwidth of typically 100 kHz and provides FM deviation of 0 to 100 kHz. AC or DC coupled FM can be selected. Phase modulation is provided with a 3 dB bandwidth of 10 kHz and deviation range of 0 to 10 radians.
Amplitude modulation with a 1 dB bandwidth of typically 30 kHz and with modulation depths of up to 99.9% is available with a resolution of 0.1%. Pulse modulation is available as standard with typical rise and fall times of less than 10 μs and 40 dB on/off ratio.
The instrument also accepts one or two logic level inputs to produce a 2-level or 4-level FSK modulated output. The required FM deviation is set by keyboard entry.
The external input voltage required for specified modulation is 1 V RMS (1.414 V peak). To accommodate other signal levels, Automatic Level Control (ALC) can be selected which provides correctly calibrated modulation for inputs between 0.75 and 1.25 V RMS.
A modulation ON/OFF soft key simplifies the testing of signal-to noise-ratio.
1-2 46882/439

Incrementing

All major parameters can be incremented or decremented in step sizes entered via keyboard entry or remotely. If no step size is entered for a parameter, the steps are preset to 1 kHz for carrier frequency, 1 kHz for modulation oscillator, 1 kHz for FM deviation, 0.1% for AM depth, 0.01 rad for ΦM and 1 dB for output level.
In addition, the rotary control knob can be used to vary the parameter with the sensitivity of the knob being changed by means of the [×10] and [÷10] keys.
Control knob operation can be assigned for the adjustment of one parameter, while another parameter is adjusted by the increment and decrement keys. By this means two parameters, for example carrier frequency and RF level, can be adjusted simultaneously.

Frequency sweep

The sweep capability of the instrument allows comprehensive testing of systems. Four parameters are used to specify sweep; start, stop, step size and time per step, all of which may be specified by the user. The sweep can be paused at any time and the frequency and level manually altered. During the sweep the RF level can be altered using the rotary control. Sweep triggering can be single shot or continuous and can be initiated directly or on the detection of a trigger. The triggering signal may either be programmed or from a TTL signal applied to the rear-panel TRIGGER 1 input. When frequency coupling is enabled, the coupled sources will track with the swept source.
GENERAL INFORMATION

Memory

The instrument provides both non-volatile and volatile memory for storing instrument settings. The non-volatile memory provides 100 full instrument settings and 100 settings of carrier frequency only. The volatile memory (RAM) also provides 100 instrument settings. Any one of the non-volatile instrument settings can be selected as the power-up setting for the instrument.
Software protection
To prevent accidental interference with the contents of internal memories, internal data is protected.
Programming
A GPIB interface is fitted so that all functions are controllable via the interface bus which is designed to the IEEE Standard 488.2. The instrument can function both as talker and listener. The instrument also has an RS-232 interface which uses the common GPIB command set to control the instrument and also allow new software upgrades or applications to be downloaded into the instrument.
Calibration data
All alignment data is digitally derived. Realignment can be undertaken, without removing covers, by protected front-panel functions or via the GPIB interface.
Spectral purity
With an SSB phase noise performance of typically −121 dBc/Hz at 20 kHz offset from a 1 GHz carrier, these instruments can be used for both in-channel and adjacent channel receiver measurements. Harmonically-related signals and non-harmonics are typically better than 30 dBc and 60 dBc respectively.
Calibration
This instrument has a recommended two-year calibration interval after which it should be returned for recalibration (for addresses refer to ‘International Service Centers’ section at end of manual).
46882/439 1-3
GENERAL INFORMATION

Performance data

Carrier frequency
Range: 10 kHz to 2.4 GHz with a resolution of 1 Hz. Accuracy: As frequency standard.
RF output
Range
Individual outputs:
Combined output:
Resolution: 0.1 dB. RF level units:
Accuracy:
* This specification does not apply to external RF input signals to combiner. † Level accuracy is unspecified below 100 kHz for levels greater than +6 dBm.
RF level tracking* (over a temperature range of +17°C to +27°C):
Attenuator hold: Inhibits operation of the step attenuator from the level at which the key
Level accuracy is unspecified below 1 MHz.
137 dBm to +24 dBm (output power above +20 dBm is uncalibrated for carrier frequencies above 1.2 GHz).
137 dBm to +4 dBm (settable to +10 dBm) (output power above 4 dBm is uncalibrated for carrier frequencies above 1.2 GHz; output power is uncalibrated at all levels for carrier frequencies below 1 MHz).
Maximum output is reduced by 5 dB when pulse modulation is selected and/or by up to 6 dB when AM is selected, dependent upon set AM depth.
Units may be set to μV, mV, EMF or PD; dB relative to 1 μV, 1 mV, EMF or PD; or dBm. Conversion between dB and linear units may be achieved by pressing the appropriate units key (dB or V, mV, μV). The output level can be normalized for 75 Ω operation with an external impedance converter (applies to all outputs simultaneously).
Up to 1.2 GHz (over temperature range 17°C to 27°C):
RF level
Individual outputs ±0.8 dB ±1.0 dB
RF level
Combiner output ±1.0 dB
Up to 2.4 GHz (over temp range of 17°C to 27°C):
RF level
Individual outputs ±1.6 dB ±2.0 dB
RF level
Combiner output ±2.0 dB
Temp stability <1.2 GHz >1.2 GHz
dB/°C
The relative level accuracy between any two or more combined signals of equal amplitude is typically:
18 to +4 dBm <18 dBm
is enabled. Usable for a level reduction of at least 10 dB. Typical accuracy ±3 dB.
127 dBm to +6 dBm
>127 dBm to
+4 dBm‡
127 dBm to +6 dBm
>127 dBm to
0 dBm
<±0.02 <±0.04
1 MHz1.2 GHz 1.2 GHz2.4 GHz
±0.3 dB ±0.6 dB ±0.6 dB ±1.2 dB
+6 dBm to +24 dBm†
+6 dBm to
+20 dBm
1-4 46882/439
GENERAL INFORMATION
VSWR
Individual outputs:
Combined output: Output VSWR is less than 1.22:1 for carrier frequencies between
Output connector: Output protection
Individual outputs:
Combined output:
Spectral purity
Harmonics:
Individual outputs:
Combined output:
Non-harmonics (for offsets >3 kHz):
Isolation: Better than 80 dB between individual outputs in use.
Intermodulation:
For output levels less than 5 dBm, output VSWR is less than 1.5:1 for carrier frequencies up to 1.2 GHz and less than 1.7:1 up to 2.4 GHz.
1 MHz and 1.2 GHz, and less than 1.32:1 up to 2.4 GHz. 50 Ω, type N connector to MIL 390123D.
Protected from a source of reverse power up to 50 W from 50 Ω, or 25 W from a source VSWR of 5:1. Protection circuit can be reset from the front panel or via the GPIB or RS-232 interface.
No reverse power protection. Maximum total safe power 0.5 W.
Typically better than 30 dBc for RF levels up to +6 dBm and typically better than 25 dBc for RF levels up to +18 dBm (+14 dBm above
1.2 GHz). Typically better than 30 dBc for RF levels up to 14 dBm and typically
better than 25 dBc for RF levels up to +4 dBm (0 dBm above
1.2 GHz). Harmonics unspecified below 1 MHz. Better than 70 dBc for carrier frequencies up to 1 GHz;
better than 64 dBc for carrier frequencies above 1 GHz; better than 60 dBc for carrier frequencies above 2 GHz.
Better than 60 dB from a used individual output to the combiner output. Better than 40 dB between the combiner output and an unused individual output.
At an RF output level of 0 dBm on the combiner into a load VSWR of 2:1 or better:
Frequency range 2-tone intermod*
10 MHz to 2.4 GHz
5 MHz to 10 MHz
Usable but unspecified down to 1 MHz
<−80 dBc <−75 dBc
*Third-order intermodulation products.
Residual FM (FM off): Less than 4.5 Hz RMS deviation in a 300 Hz to 3.4 kHz unweighted
SSB phase noise:
Carrier leakage:
External RF input: The following applies when an external input is connected at the
Insertion loss: Frequency range: Return loss: Max input power:
Intermodulation levels reduce with reducing RF levels.
bandwidth at a carrier frequency of 1 GHz. Typically <1 Hz at 249 MHz, <2 Hz at 501 MHz, <3 Hz at 1001 MHz,
<6 Hz at 2001 MHz. Better than 124 dB/Hz at 20 kHz offset from a 470 MHz carrier.
Typically better than 121 dBc/Hz at 20 kHz offset from a 1 GHz carrier.
Less than 0.5 μV PD at the carrier frequency into a 2-turn 25 mm diameter loop 25 mm from the surface of the signal generator.
rear panel and the combiner is set up for ‘independent’ external RF input.
14.75 dB ±1 dB. 10 kHz to 4 GHz (usable to 5 GHz). >20 dB to 2.4 GHz.
0.5 W.
46882/439 1-5
GENERAL INFORMATION
Modulation
Frequency modulation
Deviation: 0 to 100 kHz. Resolution: 3 digits or 1 Hz. Accuracy: ±5% at 1 kHz modulation rate. Bandwidth (1 dB): DC to 100 kHz (DC coupled),
Group delay: Carrier frequency offset: Less than 1% of the set frequency deviation when DC coupled. Distortion: Less than 1% at 1 kHz rate for deviations up to 100 kHz,
Modulation source: Internal modulation oscillator or external via front-panel BNC.
FSK
Modes: Data source: Frequency shift: Variable up to ±100 kHz. Accuracy: As FM deviation accuracy. Timing jitter: Filter:
FM, AM or phase modulation can be applied to the carriers generated by each signal source from independent internal or external modulation sources. The internal modulation sources are capable of generating two simultaneous signals into any one of the modulation channels. Each internal and external modulation source can be enabled simultaneously to produce combined amplitude and frequency (or phase) modulation. Pulse modulation can be applied to each of the carriers from external pulse sources. The pulse modulation can be used in combination with the other forms of modulation. 2-level or 4-level FSK modulation can be applied to each carrier using data from an external source.
10 Hz to 100 kHz (AC coupled), 20 Hz to 100 kHz (AC coupled with ALC).
Less than 5 μs to 100 kHz.
typically 0.3% at 1 kHz rate for deviations up to 10 kHz. Less than 3% at 1 kHz rate and deviations up to 100 kHz for carrier frequencies below 50 MHz.
2-level or 4-level FSK. External data via rear-panel 25-way D-type connector.
±3.2 μs.
th
8
-order Bessel, −3 dB at 20 kHz.
Phase modulation
Deviation range: 0 to 10 radians. Resolution: 3 digits or 0.01 radians. Accuracy at 1 kHz: ±5% of indicated deviation excluding residual phase modulation. Bandwidth (3 dB): 100 Hz to 10 kHz. Distortion: Less than 3% at 10 radians at 1 kHz modulation rate. Typically
Modulation source: Internal LF generator or external via front panel BNC.
Amplitude modulation
Individual outputs For carrier frequencies <500 MHz, usable to 1.5 GHz. Combined output Unspecified below 5 MHz; usable to 1 MHz. Otherwise as for
Range: 0 to 99.9%. Resolution: 0.1%. Accuracy*: ±5% of set depth at 1 kHz rate, over temperature range 17°C to
Bandwidth (1 dB): DC to 30 kHz (DC coupled),
Distortion*: <1.5% at 1 kHz rate for modulation depths up to 30%,
Modulation source: Internal LF generator or external via front panel BNC.
<0.5% for deviations up to 1 radian at 1 kHz.
individual outputs.
27°C. Temperature coefficient <0.02%/°C.
10 Hz to 30 kHz (AC coupled), 20 Hz to 30 kHz (AC coupled with ALC).
<2.5% at 1 kHz rate for modulation depths up to 80%.
1-6 46882/439
GENERAL INFORMATION
ΦM on AM:
*For RF levels not exceeding +10 dBm (individual output) or 4 dBm (combined output).
Pulse modulation
Carrier frequency range: 32 MHz to 2.4 GHz, usable to 10 MHz. RF level range: Maximum guaranteed output is reduced by 5 dB when pulse
RF level accuracy: When pulse modulation is enabled, adds ±0.5 dB to the RF level
Control:
On-off ratio: Rise and fall time: Overshoot: Less than 1 dB
Modulation oscillator
Frequency range: 0.01 Hz to 20 kHz with a resolution of 0.01 Hz. Frequency accuracy: As frequency standard. Distortion: Less than 0.1% THD at 1 kHz. Waveforms: Sine to 20 kHz, triangle or square wave to 3 kHz. Square wave jitter: Audio output: The modulation oscillator signal from each source is available from
External modulation
Input level: 1 V RMS (1.414 V peak) sine wave for set deviation. Maximum safe
Input impedance: Modulation ALC: Levels the applied external modulation over the range 0.75 to 1.25 V
Sweep mode:
Control parameters:
Step time: Trigger:
Frequency standard
TCXO: 10 MHz. Temperature stability: Better than ±5 in 10 Aging rate: Less than ±1 in 10 External input/output: Rear-panel BNC connector accepts an input of 1 MHz or 10 MHz at
Remote control
GPIB interface
Capabilities:
Typically 0.1 radian at 30% depth at 470 MHz.
modulation is selected.
accuracy specification. Front-panel BNC connector with an input impedance of 10 k Ω nominal.
A logical ‘1’ (3.5 to 5 V) turns the carrier on, a logical ‘0’ (0 to 1 V) turns the carrier off. Maximum input is ±15 V.
Better than 45 dB below 1.2 GHz, better than 40 dB above 1.2 GHz. Less than 10 μs.
The internal modulation oscillator for each signal source is capable of generating one or two modulation tones simultaneously in one modulation channel.
Less than 6.4 μs on any edge.
the modulation input/output BNC connector at a nominal level of 2 V RMS EMF from a 600 Ω source impedance.
A front-panel external modulation input/output BNC connector is provided.
input is ±15 V. 100 kΩ nominal.
RMS sine wave. High and low indicators in display indicate when the input is outside leveling range.
The carrier frequency of one source can be swept. To enable more than one source to be swept the coupling facility must be invoked.
Start/stop values of carrier frequency, frequency step size and time per step.
50 ms to 10 s per step. A trigger input is available on a rear-panel BNC connector and can
be used in single, continuous, start/stop or single-step mode.
7
over the operating range 0 to 55°C.
6
per year.
220 mV RMS to 1.8 V RMS into 1 kΩ. Rear-panel BNC connector provides an output of 10 MHz at a
nominal level of 2 V pk-pk into 50 Ω.
All signal source parameters except the supply switch are remotely programmable.
Designed in accordance with IEEE 488.2. Complies with the following subsets as defined in IEEE Std 488.1:
SH1, AH1, T6, L4, SR1, RL1, PP0, DC1, DT1, C0, E2.
46882/439 1-7
GENERAL INFORMATION
RS-232:
Connector: Baud rate: Handshake:
Electrical interface:
Electromagnetic compatibility
Safety
Rated range of use
Conditions of storage and transport
All signal source parameters except the supply switch are remotely programmable.
9-way male D-type 300 to 9600 bit/s. Hardware: DTR, RTS, CTS and DSR.
Software: XON and XOFF. Interface to EIA-232-D.
Conforms with the protection requirements of Council Directive 89/336/EEC.
Conforms with the limits specified in the following standards: IEC/EN 61326-1 : 1997, RF Emission Class B, Immunity Table 1, Performance Criterion B
Conforms with the requirements of EEC Council Directive 73/23/EEC and Standards IEC/EN 61010-1 : 1993.
This instrument complies with the requirements of BS EN 61010-1/IEC 61010-1, for Class 1 portable equipment and is for use in a pollution degree 2 environment. The equipment is designed to operate from an installation category 2 supply.
Unless otherwise indicated, specification is met over the temperature range 0 to +55°C (32 to 131°F), humidity up to 93% at +40°C (104°F) and elevation up to 3050 m (10 000 ft).
The instrument can be stored at temperatures of −40 to +71°C (-40 to 160°F), in humidities up to 93% at +40°C (104°F) and at elevations up to 4600 m (15 000 ft).
Power requirements Calibration interval
Dimensions and weight Height Width Depth Weight
90 to 132 V, or 188 to 255 V at 47 to 63 Hz, 250 VA maximum. 2 years.
177 mm 419 mm 488 mm 16 kg 7 in 16.5 in 19.2 in 35 lb
(Dimensions over projections but excluding front panel handles.)
Options
Option 1: 3-source generator
Includes three signal sources.
Option 3: High stability frequency standard
Replaces the internal TCXO with a high stability OCXO. Specification as standard instrument with the following exceptions:
Aging rate: Stability: Better than ±5 in 10 Warm-up time: Within 2 in 10
<±2.5 in 10
20°C.
Option 4: Rear output connections (all inputs/outputs)
All front-panel connectors are relocated on the rear panel for rack mounted operation. The specification is not altered.
7
per year, <±5 in 109 per day after 2 months’ continuous use.
8
over the temperature range 0 to 50°C.
7
of final frequency 10 minutes after switch-on at a temperature of
1-8 46882/439

Versions, options and accessories

When ordering please quote the full ordering number information.
Ordering numbers Versions
2026 10 kHz to 2.4 GHz MultiSource Generator with two signal sources.
Options
Option 1 Three internal signal sources. Option 3 High-stability frequency standard. Option 4 Rear-panel outputs.
Supplied accessories
AC power supply lead (see ‘Power cords’, Chapter 2).
46882/439 Operating manual (this document).
Optional accessories
54311/208 50/75 Ω adapter. 46882/295 Maintenance Manual 46880/094 Service manual (consists of Operating manual (this document) plus
Maintenance manual). 43129/189 GPIB lead assembly, 1.5 m. 46884/649 RS-232 cable, 9-way female to 25-way female, 1.5 m. 46884/650 RS-232 cable, 9-way female to 9-way female, 1.5 m. 46884/293 Rack-mounting kit (with slides) for rack cabinets with depths from
480 to 680 mm. 46884/294 Rack-mounting kit (with slides) for rack cabinets with depths from
680 to 840 mm. 46884/931 Rack-mounting kit containing front mounting brackets only. 46662/614 Soft carrying case. 59999/724 TEM cell. 54112/165 Hard carrying case.
GENERAL INFORMATION
46882/439 1-9
GENERAL INFORMATION
46882/439 1-11
Contents
Chapter 2

INSTALLATION

Mounting arrangements.................................................................................................................2-2
Installation requirem
Ventilation
Class I power cords Goods-in checks Connecting to supply
.........................................................................................................................................2-5
Fuse General purpose interface bus (GPIB)
GPIB cable connection
GPIB connector contact assignm
IEEE to IEC conversion
Interface bus connection RS-232 interface
RS-232 connector Auxiliary port connector
FSK operation Rack m Routine safety testing and inspection Cleaning
Putting into storage
ounting...............................................................................................................................2-9
.......................................................................................................................................2-10
Cleaning the LCD window
ents................................................................................................................2-2
..............................................................................................................................2-2
.................................................................................................................2-2
.............................................................................................................................2-5
.....................................................................................................................2-5
...........................................................................................2-5
...........................................................................................................2-5
ents......................................................................................2-6
..........................................................................................................2-6
.........................................................................................................2-7
............................................................................................................................2-7
...................................................................................................................2-7
................................................................................................................2-7
.........................................................................................................................2-8
.............................................................................................2-9
...................................................................................................2-10
......................................................................................................................2-10
List of tables
Table 2-1 Auxiliary port contact assignments ..............................................................................2-8
Table 2-2 Auxiliary port inputs for 2FSK.....................................................................................2-8
Table 2-3 Auxiliary port inputs for 4FSK
List of figures
Fig. 2-1 GPIB connector contact assignments (viewed from rear of instrument).........................2-6
Fig. 2-2 IEEE to IEC conversion..................................................................................................2-6
Fig. 2-3 RS-232 connector (viewed from Fig. 2-4 25-way
.....................................................................................2-8
rear of instrument) ......................................................2-7
AUXILIARY PORT connector.......................................................................... 2-7
46882/439 2-1
INSTALLATION
WARNING
Initial visual inspection
After unpacking the instrument, inspect the shipping container and its cushioning material for signs of stress or damage. If damage is identified, retain the packing material for examination by the carrier in the event that a claim is made. Examine the instrument for signs of damage; do not connect the instrument to a supply when damage is present, internal electrical damage could result in shock if the instrument is turned on.

Mounting arrangements

Excessive temperatures may affect the performance of the instrument. Completely remove the plastic cover, if one is supplied over the case, and avoid standing the instrument on or close to other equipment which is hot.

Installation requirements

Ventilation

This instrument is forced-air cooled by a fan mounted on the rear panel. Air must be allowed to circulate freely through the ventilator grills located on the side and underside of the instrument. Before switching on the instrument, ensure that the fan outlet on the rear panel is not restricted (i.e. clearance of at least 75 mm (3 in) at the rear, 25 mm (1 in) at each side, 15 mm (0.5 in) on the underside). Failure to provide adequate clearances will increase internal temperatures and reduce the instrument’s reliability, so that its performance may not meet specification.
Class I power cords (3-core)
General
When the equipment has to be plugged into a Class II (ungrounded) 2-terminal socket outlet, the cable should either be fitted with a 3-pin Class I plug and used in conjunction with an adapter incorporating a ground wire, or be fitted with a Class II plug with an integral ground wire. The ground wire must be securely fastened to ground. Grounding one terminal on a 2-terminal socket will not provide adequate protection.
In the event that a molded plug has to be removed from a lead, it must be disposed of immediately. A plug with bare flexible cords is hazardous if engaged in a live socket outlet.
Power cords with the following terminations are available from IFR Ltd. Please check with your local sales office for availability.
2-2 46882/439
This equipment is provided with a 3-wire (grounded) cordset which includes a molded IEC 320 connector for connection to the equipment. The cable must be fitted with an approved plug which, when plugged into an appropriate 3-terminal socket outlet, grounds the case of the equipment. Failure to ground the equipment may expose the operator to hazardous voltage levels. Depending upon the destination country, the color coding of the wires will differ:
Wire ended
INSTALLATION
Country IEC 320 plug type IFR part number
GREEN/YELLOW EARTH
Universal Straight through 23424-158 Universal Right angled 23424-159
BROWN LIVE
BLUE NEUTRAL
North America Harmonized
Line (Live) Black Brown Neutral White Blue Ground (Earth) Green Green/Yellow
HARMONISED-WIRE ENDED
C3509
British
Country IEC 320 plug type IFR part number
United Kingdom Straight through 23422-001 United Kingdom Right angled 23422-002
The UK lead is fitted with an ASTA approved molded plug to BS 1363. A replaceable 13 A fuse to BS 1362 is contained within the plug. This
fuse is only designed to protect the lead assembly. Never use the plug with the detachable fuse cover omitted or if the cover is damaged.
The fuse(s) or circuit breaker to protect the equipment is fitted at the back of the equipment.
EARTH
NEUTRAL
LIVE
UNITED KINGDOM
C3510
North American
Country IEC 320 plug type IFR part number
North American Straight through 23422-004 North American Right angled 23422-005
The North American lead is fitted with a NEMA 5-15P (Canadian CS22.2 No 42) plug and carries approvals from UL and CSA for use in the USA and Canada.
Continental Europe
Country IEC 320 plug type IFR part number
Europe Straight through 23422-006 Europe Right angled 23422-007
The Continental European lead is fitted with a right angle IEC83 standard C4 plug (CEE 7/7) which allows it to be used in sockets with either a male earth pin (standard C 3b) or side earth clips (standard C 2b) the latter is commonly called the German ‘Schuko’ plug. In common with other Schuko style plugs, the plug is not polarized when fitted into a Schuko socket. The lead carries approvals for use in Austria, Belgium, Finland, France, Germany, Holland, Italy, Norway and Sweden. Note that this plug will not fit Italian standard CEI 23 not be used in Denmark given that the earth connection will not be made.
EARTH
NEUTRAL
U.S./CANADA/KOREA
EARTH
LIVE
NEUTRAL
EARTH
CONTINENTAL
EUROPE
-16 outlets. The lead should
LIVE
C3511
C3512
46882/439 2-3
INSTALLATION
Français
Deutsch
Le câble d’alimentation d’Europe Continentale est muni d’un connecteur mâle à angle droit type CEI83, standard C4 (CEE 7/7), qui peut être utilisé dans une prise femelle à ergot de terre (standard C 3b) ou à clips latéraux (standard C 2b), cette dernière étant communément appelée prise “Schuko” allemande. De la même façon que les autres connecteurs de type Schuko, celui
-ci
n’est pas polarisé lorsqu’il s’adapte à une prise femelle Schuko. Ce câble d’alimentation est homologué en Allemagne, Autriche, Belgique, Finlande, France, Hollande, Italie, Norvège et Suède. A noter que ce connecteur n’est pas compatible avec les prises de courant italiennes au standard CEI 23
-16. Ce câble ne doit pas être utilisé au Danemark à cause du défaut de connexion
de masse.
Das kontinentaleuropäische Netzkabel ist mit einem rechtwinkeligen Stecker nach IEC83 C4 (CEE7/7) Standard versehen, welcher sowohl in Steckdosen mit Erde
-Stift (Standard C 3b) oder
seitlichen Erdeklemmen, im allgemeinen “Schukosteckdose” genannt, paßt. Üblicherweise ist der Schukostecker bei Verwendung in Schukosteckdosen nicht gepolt. Dieses Netzkabel besitzt Zulassung für Österreich, Belgien, Finnland, Frankreich, Deutschland, Holland, Italien, Norwegen und Schweden.
Hinweis: Dieser Schukostecker paßt nicht in die italienischen Standardsteckdosen nach CEI 23
-16
Norm. Dieses Netzkabel sollte nicht in Dänemark verwendet werden, da hier keine Erdeverbindung hergestellt wird.
Español
El cable de alimentación tipo Europeo Continental dispone de una clavija C4 normalizada IEC83 (CEE 7/7) que permite su utilización tanto en bases de enchufe con toma de tierra macho (tipo C 3b) o con toma de tierra mediante contactos laterales (tipo C 2b) que, en este último caso, suele denominarse “Schuko”. Al igual que cualquier otra clavija tipo Schuko, las conexiones a red no están polarizadas cuando se conectan a una base tipo Schuko. El cable lleva autorización para su uso en Austria, Bélgica, Finlandia, Francia, Alemania, Holanda, Italia, Noruega y Suecia. Observe que este cable no se adapta a la norma italiana CEI 23
-16. El cable no debe utilizarse en
Dinamarca en el caso de no efectuarse conexión a tierra.
Italiano
I cavi d’alimentazione per l’Europa continentale vengono forniti terminati con una spina ad angolo retto del tipo C4 secondo lo standard IEC83 (CEE 7/7) che può essere usato in prese in cui la terra può essere fornita o tramite connettore maschio (C 3b) o tramite clips laterali (C 2b), quest’ultima comunemente detta di tipo tedesca “Schuko”. Questa spina, quando collegata ad una presa Schuko, non è polarizzata.
Il cavo può essere usato in Austria, Belgio, Finlandia, Francia, Germania, Olanda, Norvegia, Svezia ed Italia. E’ da notare che per l’Italia questo non risponde allo standard CEI 23
-16.
Questa spina non dovrebbe invece essere usata in Danimarca in quanto non realizza il collegamento di terra.
2-4 46882/439

Goods-in checks

The following goods-in check verifies that the instrument is functioning correctly, but does not verify conformance to the listed specification. To verify that the instrument conforms to the specification given in Chapter 1, refer to Chapter 7, ‘Acceptance testing’.
(1) Ensure that the correct fuse is fitted (accessible from the rear panel) and connect the
instrument to the supply. (2) Switch on and check that a display is present. (3) If the instrument appears to be completely dead, carry out the following: Check that the mains power supply line is providing power to the instrument. Check that the mains fuses have not blown.

Connecting to supply

Ensure that the AC supply is correctly connected to the POWER SUPPLY socket. For supplies in the range 90132 V and 188264 V the PSU automatically selects the appropriate range. There is no manual voltage range selection provided.
Fuse
INSTALLATION
For the AC voltage range of 90264 V the fuse rating is 4 A-T (time lag). The AC fuse is a cartridge type measuring 20 mm
The fuse-holder is integral with the rear-panel 3-pin supply plug. For access to change the fuse, use a screwdriver to lever out the holder.
× 5 mm.

General purpose interface bus (GPIB)

The GPIB interface built into the instrument enables the signal generators to be remotely controlled to form part of an automatic measuring system.
GPIB cable connection
Connection to other equipment which has a 24-way connector to IEEE Standard 488 is made using the rear-panel GPIB 1 socket. For this purpose, the GPIB cable assembly, available as an optional accessory, (see Chapter 1, ‘Versions, options and accessories’) may be used. A second socket, GPIB 2, may be fitted as an option (not yet implemented).
46882/439 2-5
INSTALLATION
GPIB connector contact assignments
The contact assignments of the GPIB cable connector are as given in the table below and shown in Fig. 2-1.
Contact Function Contact Function
10 11 12
Fig. 2-1 GPIB connector contact assignments (viewed from rear of instrument)
IEEE to IEC conversion
An optional IEEE to IEC adapter is also available (contact your local distributor) for interfacing with systems using a 25-way bus connector to IEC Recommendation 625. The method of use is shown in Fig. 2-2.
1 2 3 4
Data I/O 1 Data I/O 2 Data I/O 3
Data I/O 4 5 6 7 8 9
EOI
DAV
NRFD
NDAC
IFC
SRQ
ATN
13 14 15 16 17 18 19 20 21 22 23 24
DataI/O 5 DataI/O 6 DataI/O 7 DataI/O 8 REN Pair with 6 Pair with 7 Pair with 8 Pair with 9 Pair with 10 Pair with 11 Logic ground
Ground shield
12 1
24 13
24
INSTRUMENT (IEEE CONNECTOR)
INSTRUMENT (IEEE CONNECTOR)
IEEE to IEC
ADAPTER
46883/408
IEEE LEAD
25
IEC LEAD
EQUIPMENT
WITH IEEE
CONNECTOR
EQUIPMENT
WITH IEC
CONNECTOR
C4577
Fig. 2-2 IEEE to IEC conversion
2-6 46882/439
Interface bus connection
The cables for the interface bus use special male-to-female connectors at both ends. This allows several connectors to be stacked one on top of another permitting several cables to be connected to the same source and secured by a lockscrew mechanism. Too large a stack, however, may form a cantilevered structure which might cause damage and should be avoided. The piggyback arrangement permits star or linear interconnection between the devices with the restriction that the total cable length for the system must be:
(1) No greater than 20 m (65 ft). (2) No greater than 2 m (6 ft) times the total number of devices (including the controller)
connected to the bus.
RS-232 interface
The RS-232 interface built into the instrument is used to reprogram the internal flash memory, and may also be used to control the instrument using the common GPIB command set.
RS-232 connector
The rear-panel male D-type RS-232 connector is shown in Fig. 2-3.
INSTALLATION
1
6
5
9
Fig. 2-3 RS-232 connector (viewed from rear of instrument)
The pin-outs for the 9-way RS-232 connector are shown below:
Contact Signal 1 DCD Data carrier detect
2 RXD Receive data 3 TXD Transmit data 4 DTR Data terminal ready 5 SG Signal ground 6 DSR Data set ready 7 RTS Request to send 8 CTS Clear to send 9 RI Ring indicator
The RS-232 interface can be connected to a personal computer’s AT connector using a null-modem cable. A suitable cable is available from IFR − see Chapter 1, ‘Versions, options and accessories’.

Auxiliary port connector

The rear-panel 25-way female D-type AUXILIARY PORT connector is shown in Fig. 2-4. This is used for FSK operation.
13
25
Fig. 2-4 25-way AUXILIARY PORT connector
46882/439 2-7
1
C0681
14
INSTALLATION
FSK operation
Data for FSK operation is carried on the contacts of the AUXILIARY PORT as shown by Table 2-1 below. The unused contacts are left unconnected.
Table 2-1 Auxiliary port contact assignments
CONTACT FUNCTION
14 15 16 17 18 19 12 0 V
Source A FSK A Source A FSK B Source B FSK A Source B FSK B Source C FSK A Source C FSK B
The frequency shifts produced by the applied data are as shown in Table 2-2 below for 2FSK and in Table 2-3 below for 4FSK.
Table 2-2 Auxiliary port inputs for 2FSK
FSK A FSK B SOURCE A pin 14 pin 15 SOURCE B pin 16 pin 17 SHIFT SOURCE C pin 18 pin 19 LOGIC LEVELS 1 *0 +D 0 *0
D
where D is the set deviation value. *Tie FSK B as 0 or leave floating.
Table 2-3 Auxiliary port inputs for 4FSK
FSK A FSK B SOURCE A pin 14 pin 15 SOURCE B pin 16 pin 17 SHIFT SOURCE C pin 18 pin 19 1 0 +D LOGIC LEVELS 1 1 +D/3 0 1 0 0
where D is the set deviation value.
D/3
D
2-8 46882/439

Rack mounting

The instrument, which is normally supplied for bench mounting, may be mounted in a standard 19 inch rack (see Chapter 1, ‘Versions, options and accessories’). There are two slide rack mounting kits to accommodate different depths of cabinet. These kits include full fitting instructions. A rack mounting kit without slides is also available which contains front-panel mounting brackets only.

Routine safety testing and inspection

In the UK the ‘Electricity at Work Regulations’ (1989) section 4(2) places a requirement on the users of equipment to maintain it in a safe condition. The explanatory notes call for regular inspections and tests together with a need to keep records.
The following electrical tests and inspection information is provided for guidance purposes and involves the use of voltages and currents that can cause injury. It is important that these tests are only performed by competent personnel.
Prior to carrying out any inspection and tests the equipment must be disconnected from the mains supply and all external signal connections removed. All tests should include the equipment’s own supply lead, all covers must be fitted and the supply switch must be in the ‘ON’ position.
The recommended inspection and tests fall into three categories and should be carried out in the following sequence:
1. Visual inspection
2. Earth bonding test
3. Insulation resistance test.
INSTALLATION
1. Visual inspection
A visual inspection should be carried out on a periodic basis. This interval is dependent on the operating environment, maintenance and use, and should be assessed in accordance with guidelines issued by the Health and Safety Executive (HSE). As a guide, this equipment, when used indoors in a relatively clean environment, would be classified as ‘low risk’ equipment and hence should be subject to safety inspections on an annual basis. If the use of the equipment is contrary to the conditions specified, you should review the safety re-test interval.
As a guide, the visual inspection should include the following where appropriate: Check that the equipment has been installed in accordance with the instructions provided (e.g. that
ventilation is adequate, supply isolators are accessible, supply wiring is adequate and properly routed).
The condition of the mains supply lead and supply connector(s).
The correct rating and type of supply fuses.
Security and condition of covers and handles.
Check the presence and condition of all warning labels and markings and supplied safety
information.
Check the wiring in re-wireable plugs and appliance connectors.
Check the cleanliness and condition of any ventilation fan filters.
Check that the mains supply switch isolates the equipment from the supply.
Check the supply indicator functions (if fitted).
If any defect is noted this should be rectified before proceeding with the following electrical tests.
2. Earth bonding tests
Earth bonding tests should be carried out using a 25 A (12 V maximum open circuit voltage) DC source. Tests should be limited to a maximum duration of 5 seconds and have a pass limit of
0.1 Ω after allowing for the resistance of the supply lead. Exceeding the test duration can cause damage to the equipment. The tests should be carried out between the supply earth and exposed
46882/439 2-9
INSTALLATION
case metalwork, no attempt should be made to perform the tests on functional earths (e.g. signal carrying connector shells or screen connections) as th is will result in damage to the equipment.
3. Insulation tests
A 500 V DC test should be applied between the protective earth connection and combined live and neutral supply connections with the equipment supply switch in the ‘on’ position. It is advisable to make the live/neutral link on the appliance tester or its connecto r to avoid the possibility of returning the equipment to the user with the live and neutral poles linked with an ad-hoc strap. The test voltage should be applied for 5 seconds before taking the measurement.
IFR Ltd employs reinforced insulation in the construction of its products and hence a minimum pass limit of 7 MΩ should be achieved during this test.
Where a DC power adapter is provided with the equipment, the adapter must pass the 7 MΩ test limit.
We do not recommend dielectric flash testing during routine safety tests. Most portable appliance testers use AC for the dielectric strength test which can cause damage to the supply input filter capacitors.
4. Rectification
It is recommended that the results of the above tests are recorded and checked during each repeat test. Significant differences between the previous readings and measured values should be investigated.
If any failure is detected during the above visual inspection or tests, the equipment should be disabled and the fault should be rectified by an experienced Service Engineer who is familiar with the hazards involved in carrying out such repairs.
Safety critical components should only be replaced with equivalent parts, using techniques and procedures recommended by IFR Ltd.
The above information is provided for guidance only. IFR Ltd designs and constructs its products in accordance with International Safety Standards such that in normal use they represent no hazard to the operator. IFR Ltd reserves the right to amend the above information in the course of its continuing commitment to product safety.

Cleaning

Before commencing any cleaning, switch off the instrument and disconnect it from the supply. The exterior surface of the case may be cleaned using a soft cloth moistened in water. Do not use aerosol or liquid solvent cleaners.
Cleaning the LCD window
To prevent damage to the LCD window, care should be taken not to scratch the surface during use and also when cleaning. The LCD window should be cleaned by wiping a slightly damp, soft, lint-free cloth gently over the surface.

Putting into storage

If the instrument is to be put into storage, ensure that the following conditions are maintained: Temperature range: Humidity: Less than 93% at 40°C
40 to 70°C
2-10 46882/439
Contents
Chapter 3

LOCAL OPERATION

Introduction....................................................................................................................................3-4
Conventions...................................................................................................................................3-4
Front-panel controls and connectors Rear-panel connectors
First-time use
Switching on Display Selecting functions and keyboard entry
eter adjustment...................................................................................................................3-13
Param Displaying shifts
biner summary......................................................................................................................3-15
Com
Individual source operation
Signal source selection Carrier frequency selection
Carrier on/off
RF level selection
Choice of units Reverse power protection
odulation selection....................................................................................................................3-19
M
odulation modes .......................................................................................................................3-19
M Mode selection
Sig gen screens
Internal waveform
odulation source adjustment.............................................................................................. 3-21
M
External source coupling
DCFM nulling
odulation ON/OFF....................................................................................................................3-23
M
plitude modulation selection..................................................................................................3-23
Am Frequency Phase m Pulse m FSK selection
Sw
eep...........................................................................................................................................3-27
Sweep operation
Sweep control
Utilities
Utility m Selection m Display adjustm Frequency standard selection (m Carrier phase adjustm RF level units selection (m
75 Ω impedance selection (menu 1) ..................................................................................3-34
50 Ω / Power-up options (m Default settings
odulation mode selection (menu 1) ..........................................................................................3-36
M
ote control selection (menu 1)..............................................................................................3-37
Rem Background error reporting (m Protection locking and unlocking (m Selection m Software inform Hardware inform Patent inform Display blanking (m
................................................................................................................................3-9
..................................................................................................................................3-9
...........................................................................................................................................3-9
modulation selection ..................................................................................................3-24
odulation selection..........................................................................................................3-24
odulation selection...........................................................................................................3-24
...............................................................................................................................3-25
........................................................................................................................................3-31
enu selection..................................................................................................................3-31
enu 1.......................................................................................................................... 3-31
enu 2.......................................................................................................................... 3-39
ation (menu 2)........................................................................................................3-40
....................................................................................................................3-6
..........................................................................................................................3-14
.................................................................................................................3-17
..........................................................................................................3-17
........................................................................................................................3-18
.........................................................................................................................3-18
......................................................................................................................3-18
.............................................................................................................................3-19
.....................................................................................................................3-20
selection......................................................................................................... 3-21
..............................................................................................................3-22
.......................................................................................................................3-22
...........................................................................................................................3-27
.......................................................................................................................3-28
ent (menu 1).......................................................................................................3-31
ent (menu 1)..............................................................................................3-33
enu 1) ................................................................................................3-33
enu 1)..........................................................................................................3-35
............................................................................................................................3-35
ation (menu 2)....................................................................................................3-39
ation (menu 2) ..................................................................................................3-40
enu 2)...........................................................................................................3-40
..............................................................................................3-4
.......................................................................................3-12
......................................................................................................3-17
.....................................................................................................3-18
enu 1) .......................................................................................3-32
enu 1)..........................................................................................3-37
enu 1).................................................................................3-38
46882/439 3-1
LOCAL OPERATION
Latch access utility (menu 2) .......................................................................................................3-41
Elapsed time (menu 2) .................................................................................................................3-41
RPP trip count utility (menu 2) Display test utility (m
/knob tests (menu 2)..............................................................................................................3-43
Key Calibration utility (m
Memory
Mem Storing data Mem
Mem
Mem Mem Recalling data
Error messages
Error handling
Background errors:
Foreground errors:
Error m
GPIB errors
Source-specific errors
....................................................................................................3-42
enu 2).........................................................................................................3-42
enu 2)..........................................................................................................3-43
.......................................................................................................................................3-45
ory stores..............................................................................................................................3-45
..................................................................................................................................3-46
ory protection.......................................................................................................................3-46
ory protection summary................................................................................................3-46
ory protection menu......................................................................................................3-47
ory recall..............................................................................................................................3-47
...............................................................................................................................3-48
...........................................................................................................................3-49
..............................................................................................................................3-49
...............................................................................................................3-49
................................................................................................................3-49
essage priority: .........................................................................................................3-49
...........................................................................................................................3-49
...........................................................................................................3-50
List of tables
Table 3-1 Instrument default settings..........................................................................................3-36
Table 3-2 Background errors (500−599) in priority order..........................................................3-50
Tabl Tabl
List of figures
Fig. 3-1 2026 front panel ............................................................................................................3-4
Fig. 3-2 2026 rear panel..............................................................................................................3-6
Fig. 3-3 2026 Sig Gen m Fig. 3-4 Division of the Sig Gen m Fig. 3-5 Steps m Fig. 3-6 Total shift m Fig. 3-7 Com Fig. 3-8 Sig Gen m
Fig. 3-9 RPP tripped..................................................................................................................
Fig. 3-10 M Fig. 3-11 Sig Gen m Fig. 3-12 Sig Gen m Fig. 3-13 Internal source waveform Fig. 3-14 M Fig. 3-15 External source coupling m Fig. 3-16 Sig Gen m Fig. 3-17 Sig Gen m Fig. 3-18 Sweep control screen in fixed m Fig. 3-19 Carrier sweep m Fig. 3-20 Sweep control screen in sweep mode (B and C sources coupled to A source) Fig. 3-21 Utilities selection m Fig. 3-22 Display adjustm Fig. 3-23 Frequency standard selection m Fig. 3-24 Carrier phase adjustm Fig. 3-25 RF level units selection m Fig. 3-26 50 ohm Fig. 3-27 Power up options m Fig. 3-28 M Fig. 3-29 Rem Fig. 3-30 Current background errors display
e 3-3 Foreground errors (0−399) .........................................................................................3-51
e 3-4 GPIB errors (400−499)...............................................................................................3-53
enu in normal operation showing default display................................3-9
enu (main display) into fields............................................3-11
enu ..................................................................................................................3-14
enu...........................................................................................................3-15
biner summary (for instrument with three sources fitted)....................................3-15
enu with amplitude modulation selected for the A source .........................3-17
3-18
odulation mode selection menu................................................................................3-19
enu with two internal modulation channels................................................3-20
enu with internal and external modulation sources....................................3-20
menu..................................................................................3-21
odulation source phase adjustment menu.................................................................3-21
enu...................................................................................3-22
enu with two modulation channels.............................................................3-23
enu with 4FSK selected..............................................................................3-25
ode............................................................................3-27
ode menu...........................................................................................3-27
...........3-28
enu 1............................................................................................3-31
ent utility............................................................................................3-32
enu.............................................................................3-32
ent utility...................................................................................3-33
enu......................................................................................3-34
/75 ohm calibration menu................................................................................3-34
enu...............................................................................................3-35
odulation mode selection menu................................................................................3-36
ote control utility..................................................................................................3-37
(showing example errors)....................................3-38
3-2 46882/439
LOCAL OPERATION
Fig. 3-31 Lock and unlock utility (during password entry)........................................................3-38
Fig. 3-32 Utilities selection menu 2............................................................................................3-39
Fig. 3-33 Software status display Fig. 3-34 Hardware status display Fig. 3-35 Patent inform
ation display...........................................................................................3-40
Fig. 3-36 Display blanking utility...............................................................................................
Fig. 3-37 Latch access utility......................................................................................................
Fig. 3-38 Elapsed tim
e utility......................................................................................................3-42
Fig. 3-39 RPP trip count utility...................................................................................................
Fig. 3-40 Display test utility .......................................................................................................
Fig. 3-41 Keyboard/knob test utility...........................................................................................3
Fig. 3-42 Calibration m Fig. 3-43 Mem Fig. 3-44 Mem Fig. 3-45 Mem Fig. 3-46 Mem
ory store menu.....................................................................................................3-46
ory write protection summary.............................................................................3-46
ory write protection menu...................................................................................3-47
ory recall menu ...................................................................................................3-48
enu.........................................................................................................3-43
................................................................................................3-39
..............................................................................................3-40
3-41 3-41
3-42 3-42
-43
46882/439 3-3
LOCAL OPERATION

Introduction

This chapter explains how to:
Set up the multisource generator to produce a typical basic signal.
Select the main operating parameters; carrier frequency, output level and type of modulation.
Use the full range of supporting facilities.

Conventions

The following conventions are used in this chapter: RF OUTPUT Titles marked on the instrument panel are shown in capital letters [SETUP] Hard key titles are shown in square brackets, and
[Carrier Freq] Soft key titles are shown in italics in square brackets; for example, [Carrier
Freq] means the soft key adjacent to the Carrier Freq title box at the side of the
menu.
RF Level Messages appearing on the screen are shown in italic letters.
Front-panel controls and connectors
Parameters are selected by means of hard keys (which have their function printed on them), soft keys (which do not have any notation), a numerical key pad and a rotary control knob; see Fig. 3 below. The hard keys have functions which do not change, whereas the soft key functions are determined by the menu which is being displayed. The numerical keys are used to set parameters
to specific values which can also be varied in steps of any size by using the [ rotary control knob.
Ø][×] keys or the
-1
-1 2026 front panel
Fig. 3
3-4 46882/439
LOCAL OPERATION
SUPPLY Switches the AC supply voltage on and off.
1
[A], [B], [C] This key is repeated for each signal source. It selects A, B or C
2
as the current signal source for parameter display and adjustment. The C source is optional.
[SETUP] Displays the Setup Menu used for signal source configuration
3
[SIG GEN] Displays the main, Sig Gen, menu.
4
[SWEEP] Displays the Sweep Control screen for the current source.
5
[UTIL] Displays the Utilities Selection Menu.
6
[MEM] Displays the Memory Store/Recall Menu.
7
8
[TOTAL Δ] Soft keys Twelve function keys change notation as the menus change.
9
Numerical key pad For entering the value of a selected parameter. Minus sign and
10
[ENTER]/Units keys Determine the units of the set parameters and also used to
11
[KNOB LOCK] Pressing this key assigns control knob operation to the
12
Control knob When enabled by the [KNOB ON/OFF] key, adjusts the value
13
[KNOB ON/OFF] Enables or disables the control knob.
14
15
[×10]
16
[÷10]
17
[SET Δ] [×] Increments the value of the selected parameter.
18
[Ø] Decrements the value of the selected parameter.
19
PULSE INPUT
20
MOD I/O
21
and for selecting an application mode..
Displays the Total Shift Menu for the current source.
decimal point are included.
terminate a numerical entry.
currently selected function.
of the selected parameter.
When control knob enabled, decreases knob resolution by a factor of 10.
When control knob enabled, increases knob resolution by a factor of 10.
Displays the Steps Menu for the current source.
10 kΩ BNC connector (fitted to each signal source) which accepts a pulsed input.
100 kΩ BNC connector (fitted to each signal source) which allows an external modulating signal to be applied. Also provides a modulation oscillator output from a 600 Ω source impedance. With Option 4 this connector is fitted on th e rear panel.
22
[Σ] [RF ON/OFF] Enables or disables the associated signal source RF OUTPUT
23
RF OUTPUT
24
Displays the Combiner Summary.
or the COMBINED RF OUTPUT connector. 50 Ω type
-N connector (fitted to each signal source). Protected
against the application of reverse power of up to 50 W. With Option 4 this connector is fitted on th e rear panel.
COMBINED RF
25
OUTPUT
50 Ω type
-N connector. Note that maximum reverse power at
this connector is 0.5 W. With Option 4 this connector is fitted on the rear panel.
46882/439 3-5
LOCAL OPERATION
Rear-panel connectors
The rear-panel connectors are shown in Fig. 3-2 below.
-2 2026 rear panel
Fig. 3
COMBINED RF
1
OUTPUT (optional)
An Option 4 50 Ω type
-N connector. When fitted, replaces the
front-panel connector.
PULSE INPUT
2
(optional) MOD I/O (optional)
3
RF OUTPUT
4
(optional) EXT STD I/P BNC connector for the input of an external standard frequency
5
INT STD O/P BNC connector for the output of the internal 10 MHz standard.
6
RS232 9
7
GPIB 1 24
8
POWER SUPPLY 3
9
TRIGGER 1 BNC connector which is used for sweep triggering.
10
TRIGGER 2 Reserved.
11
An Option 4 10 kΩ BNC connector. When fitted, replaces the front-panel connector.
An Option 4 100 kΩ BNC connector. When fitted, replaces the front-panel connector.
An Option 4 50 Ω type
-N connector. When fitted, replaces the
front-panel connector.
of either 1 MHz or 10 MHz.
-way RS-232 connector used for remote control of the
instrument as well as to reprogram the internal flash memory. For contact allocation see ‘RS
-pin socket accepts standard IEEE connector to allow remote
-232 connector’ in Chapter 2.
control of the instrument.
-pin plug integral with fuse holder. Mates with AC supply
lead socket.
3-6 46882/439
LOCAL OPERATION
AUXILIARY PORT 25
12
-pin socket. Can accept external data to modulate each of the
internal sources for 2 allocation see ‘Auxiliary port connector’ in Chapter 2.
EXT I/P
13
INT O/P (optional)
14
50 Ω SMA connector. Enables a signal to be fed into the combiner from an external signal generator.
50 Ω SMA connector. Used when a third source is fitted to provide a rear-panel output. When linked to the EXT I/P socket, connects the C source output to the combiner. When this socket is not in use it must be terminated by the attached 50 Ω load to prevent signal radiation from the C source.
-level or 4-level FSK. For contact
46882/439 3-7
First-time use
First-time users can quickly become familiar with the principles of control and display by carrying out the following exercise, which demonstrates how to set up a typical basic signal, having the following parameters, on one of the signal sources:
Carrier frequency: 100 MHz, Output level: 10 dBm, Frequency modulation: 100 kHz deviation at 500 Hz mod.

Switching on

Before switching the instrument on, check that the power supply is connected and ensure that no external signal sources are connected.
Switch on by means of the SUPPLY switch and check that the display is similar to that shown in
-3 below. This shows the Sig Gen menu as it appears during normal operation.
Fig. 3 If the default display shown in Fig. 3
instrument to switch on with one of the user memories recalled, rather than using the default factory settings.
To reset to the factory settings press the [UTIL] hard key followed by the soft key sequence [Power Up Options] [Factory Power Up] [EXIT]. Then switch off and switch back on again.
Observe that the Sig Gen menu appears on the display showing the default parameters for FM, and that the panel for the A signal source is highlighted at th e bottom left of the screen. This indicates that these parameters apply only to the A source.
-3 is not obtained, a previous user may have set the
B3420
Fig. 3-3 2026 Sig Gen menu in normal operation showing default display

Display

Before entering any parameters it will be found useful to look at the effect that pressing various keys has on the display for the Sig Gen menu. This is the main display and it is divided into a number of fields as shown in Fig. 3
Signal source field
This field, at the bottom of the display, is divided into four panels, one for each of the three signal sources and one for the combiner. When a source panel is highlighted, all the parameters shown
46882/439 3-9
-4 below.
LOCAL OPERATION
on the screen apply to that source; for example, when the A panel is highlighted, the displayed carrier frequency, RF level, modulation etc., apply only to the A source. The selected signal source can be changed using the [A], [B] and [C] hard keys.
The RF output from a source may be directed to its own output socket, or re combiner (either alone or in combination with other sources) to the combiner output socket. Signal sources are combined using a menu accessed via the [SETUP] hard key.
The designation A for the A source. When A combiner.
-routed via the
Ö
O/P shows that the A source output is directed to the RF OUTPUT socket
Ö Σ
is displayed it shows that the A source output is directed to the
When no signal source is connected to the combiner the combiner panel shows appropriate not fitted is shown against source designator C.
When one or more sources are connected via the combiner to the COMBINED RF OUTPUT socket, the combiner panel displays this information by showing all combinations from
Σ =
A+B+C
Note that the signal source field is displayed in all modes.
.
Carrier frequency field
This shows the current carrier frequency setting for the selected signal source. This field is controlled by the [Carrier Freq] soft key.
When the frequency of the selected source is coupled to another source (so that it tracks it), an arrow is shown together with the other source’s identity. In Fig. 3 shown coupled to the A source by the A source panel being highlighted and the carrier frequency field.
RF level field
This shows the current RF level setting for the selected signal source. This field is controlled by the [RF Level] soft key.
When the level of the selected source is coupled to another source, an arrow is shown together with the other source’s identity (as for frequency coupling).
Frequency standard field
The type of standard is shown in this field together with its frequency. Frequency standard selection is made from a menu accessed via the [UTIL] hard key.
This field also displays Atten Lock when the attenuator lock function is enabled.
Σ
not used. When
Σ = Α
to
-4 for example, the B source is
Ö
B being shown in
Modulation state field
Here the modulation state is shown as either ENABLED or DISABLED. This is controlled by the [Mod ON/OFF] key which switches all internal modulation on or off. When pulse modulation is selected, Pulse ON or OFF is shown (an additional soft key [Pulse ON/OFF] also appears).
3-10 46882/439
Soft keys
Carrier frequency
Modulation state
Modulation
FIRST TIME USE
Frequency standardRF level
Soft keys
Fig. 3
Modulation field
This field shows all the current modulation settings for the selected signal source: type of modulation; modulation deviation/depth; modulation frequency; waveform type (shown graphically); modulation ON or OFF.
The type of modulation is selected by the [FM], [AM] and [ are shown at any time. This is because the display will already be showing the parameters for the omitted selection key.
Error message
Signal source
-4 Division of the Sig Gen menu (main display) into fields
ϕ
M] keys. Only two of the three keys
C3290
ϕ
Modulation deviation/depth is selected by the [FM Devn], [AM Depth] and [ Modulation frequency is selected using the [FM Mod Freq], [AM Mod Freq] and [
M Devn] keys.
ϕ
M Mod Freq]
keys and the value is shown on the screen against ModF:. The type of waveform (sine, triangle or square) is obtained from a menu after pressing the [Select
Waveform] key. For external modulation this key is replaced by the [Select Coupling] key.
ϕ
Internal modulation switching is controlled by the [FM ON/OFF], [AM ON/OFF] and [
M
ON/OFF] keys.
46882/439 3-11
LOCAL OPERATION
Error message field
Error messages are displayed here when, for example, you exceed a parameter limit. A list of error messages is given at the end of this chapter.
Soft key fields
These fields can hold up to 12 soft key labels. Some soft keys are used to select a field for data entry (e.g. [Carrier Freq]), in which case the soft key label will remain highlighted after being pressed to show that any subsequent data entry applies to that function.
Other soft keys may perform an action (for example, turning the modulation on or off), in which case the label will flash to acknowledge the key-press.
Some soft keys cause another menu to be displayed, in which case there is no highlighting or flashing of the label, the change of menu acknowledges the key

Selecting functions and keyboard entry

Whenever one of the main functions carrier frequency, RF level, modulation is highlighted on the main screen, making any terminated numerical entry will be accepted as being a changed parameter for that function. This enables you to enter, for example, a sequence of carrier frequencies without having to re
First of all, select the A source for adjustment by pressing the [A] key.
-press the [Carrier Freq] key for each entry.
-press.
Carrier frequency
(1) Press the [Carrier Freq] soft key to select carrier frequency as the current function. The key
label is highlighted so that the line bordering the label is increased in thickness to about 1 mm. Data entered on the key pad will now be recognized as a frequency setting and replaces the current setting.
(2) Enter 100 MHz by entering 100 on the numerical key pad and terminating with [MHz].
Observe that the Carrier Freq: display changes to 100.000 000 MHz.
If you make an error when keying in, press the function key again and key in the correct value. If this causes an error message (e.g. Err 1100: Carrier Limit) to be displayed, it can be canceled by a correct entry (e.g. by entering a value which is within limits).
RF level
(3) Press [RF LEVEL] (which causes its key label to be highlighted) to select RF level as the
current function.
(4) Enter 10 dBm by entering 10 on the numerical key pad and terminating with [dB]. Observe
that the RF Level: display changes to
(5) Press the [RF ON/OFF] key for the A signal source. Repeated pressing toggles between the
on and off states as shown by A 100 MHz, 10 dBm carrier is now being generated from the A source RF OUTPUT socket.
Modulation
(6) Press [FM Devn]. Enter 100 on the key pad and terminate with [kHz]. 100 kHz is displayed
in the modulation field.
(7) Press [FM Mod Freq]. Enter 500 on the key pad and terminate with [Hz]. ModF: 500.00 Hz
is displayed .
(8) Press[Mod ON/OFF]. Repeated pressing toggles between the on and off states as shown by
Modulation ENABLED and DISABLED at the centre of the screen. Select Modulation ENABLED.
(9) Press [FM ON/OFF]. Repeated pressing toggles between the on and off states as shown by
ON and OFF on the screen. Select ON. A 100 MHz, 10 dBm carrier is now being generated
+
10.0 dBm.
Ö O/P ON and OFF in the A source panel. Select ON. A
3-12 46882/439
at 100 kHz deviation, sine wave modulated at 500 Hz from the A source RF OUTPUT socket.

Parameter adjustment

When a function has been selected, you can increment or decrement its parameter either continuously using the control knob or in steps using the [×] and [Ø] keys. You can also simultaneously adjust two parameters by means of the [KNOB LOCK] key.
Using the control knob
You enable the control knob by pressing the [KNOB ON/OFF] key so that the parameter to be adjusted is displayed outlined by a bracket. With the control knob enabled, you can set its resolution. Press the [÷10] key to increase the bracket length by one decimal place. Similarly, press the [×10] key to decrease the bracket length by one decimal place. In this way you respectively increase or decrease the resolution of the control knob by a factor of ten.
Disabling the control knob will help to ensure that accidental changes to the set parameters are prevented.
Two-parameter adjustment
A feature of this instrument is that the [KNOB LOCK] key enables you to simultaneously and independently adjust two parameters using the control knob and the [×] [Ø] keys. Proceed as follows:
(1) Select the function to be assigned to the control knob for adjustment by pressing its soft key;
for example, [Carrier Freq]. When selected, the soft key is highlighted so that the line bordering the key label is increased in thickness to about 1 mm.
(2) Enable the control knob using the [KNOB ON/OFF] key (so that the bracket is visible above
and below the parameter).
(3) Press the [KNOB LOCK] key. Now any movement of the control knob will only adjust the
parameter of the assigned function leaving you free to select a second function − for example [RF Level] and adjust its parameter this time using the [×] and [Ø] keys. At all times the function locked to the control knob is identified by its parameter being outlined by a bracket and an inverse-video bracket symbol being displayed at the lower right of the screen.
FIRST TIME USE
46882/439 3-13
LOCAL OPERATION
Using the steps keys
The selected function’s parameter may be adjusted in steps using the [×] and [Ø] keys to respectively increment and decrement the parameter. The step size can be set as follows:
(1) Press the [SET Δ] key which causes the Steps Menu to be displayed (see Fig. 3-5 below).
This shows the step sizes of the currently selected signal source.
B3421
(2) Select [Carrier Step], enter the value on the key pad and press a terminator key. The step
value will appear on the screen. (3) Return to the Sig Gen menu by pressing [SIG GEN]. (4) Using the [×] and [Ø] keys respectively will now increment or decrement the carrier
frequency by the set value. (5) [RF Level Step], [ModFreq Step] and [FM Step], [AM Step] and [
entered in the same way. (6) Repeat as required for the other signal sources.

Displaying shifts

You can check the difference between the keyed-in value (the reference) and the current value, as well as restoring the reference either to the original value or resetting it to the new value. Proceed as follows:
(1) Press [TOTAL Δ] to display the To tal Shift Menu for the selected signal source. This
displays the amount of shift from the reference caused by using the control knob or [Ø] [×]
keys to adjust the parameters (see Fig. 3-6 below).
Fig. 3-5 Steps menu
ϕ
M Step] values can be
3-14 46882/439
FIRST TIME USE
B3422
Fig. 3-6 Total shift menu
(2) Carrier frequency and RF level, as well as modulation depth/deviation and frequency in
ϕ
combination with the [AM], [FM] and [
M] keys can be further adjusted using the
appropriate [Shift] key. The amount of shift at each key-press is that of the current step value.

Combiner summary

The [Σ] hard key may be used to display a summary of all the sources’ frequencies and levels and provides an easy means to change these parameters. This menu is also used to implement the attenuator lock function for each individual source. The function inhibits operation of the step attenuator from the level at which the key is enabled, and is usable for a lev el reduction of at least 10 dB.
(1) Press the [Σ] hard key to show the Combiner Summary similar to that shown in Fig. 3-7
below.
B3423
Fig. 3-7 Combiner summary (for instrument with three sources fitted)
(2) You can reset the carrier frequencies and RF levels for each of the sources fitted in your
instrument. Press the [Carrier Freq] or [RF Level] key for the applicable source, enter the
new value on the key pad and press a terminator key. (3) To display the individual signal source settings press the required [A], [B] or [C] key. (4) To implement the attenuator lock function, press the [Atten Lock] key for the required A, B
or C source. Atten Lock is shown on the menu (and also shown on the Sig Gen menu)
against the appropriate source parameters.
46882/439 3-15

Individual source operation

The following section describes the method of controlling the settings of the individual signal sources. The method of control can be used irrespective of the routing of the signal source output, whether to its own RF OUTPUT or to the COMBINED RF OUTPUT, and irrespective of any coupling that may have been set up.

Signal source selection

Select the required signal source by pressing the [A], [B] or [C] key. The selection is acknowledged by the A, B or C panel at the bottom of the display being highlighted. Having entered the parameters for that signal source you can then repeat the procedure for each additional source. In Fig. 3-8 below the parameters for the A source are shown.
Fig. 3-8 Sig Gen menu with amplitude modulation selected for the A source

Carrier frequency selection

You can enter the carrier frequency in the range 10 kHz to 2.4 GHz to a resolution of 1 Hz. (1) Press [SIG GEN] to show the Sig Gen menu with the current carrier frequency displayed. (2) Press the [Carrier Freq] soft key to select carrier frequency as the current function. (3) Enter the required value using the numerical key pad. Terminate using the [Hz], [kHz],
[MHz] or [GHz] key. If a value outside the specified range is requested, an error message is
displayed and the instrument is automatically set to the end of the range. (4) You can then adjust the frequency either in steps using the [Ø],[×] keys or by using the
control knob for continuous adjustment. The default increment/decrement is 1 kHz. (5) You can check the current amount of offset from the reference carrier frequency by pressing
[TOTAL Δ]. This causes the Total Shift Menu to be displayed. (6) On the Total Shift Menu pressing the [Return Value] key returns you to the reference carrier
frequency; pressing [Transfer Value] selects the currently displayed frequency as the
reference frequency. (7) Pressing [SIG GEN] returns you to the Sig Gen menu.
B3424
46882/439 3-17
LOCAL OPERATION
Carrier on/off
The carrier can be switched on or off at any time by means of the [RF ON/OFF] key. This effectively switches the output on and off, retaining the 50 Ω

RF level selection

You can enter the RF level in the range 137 to +24 dBm (to +20 dBm above 1.2 GHz). (1) Press [SIG GEN] to show the Sig Gen menu with the current RF level displayed. (2) Press the [RF Level] soft key to select RF level as the current function. (3) Enter the required value using the numerical key pad. For voltage terminate using the [μV],
[mV] or [V] key. For logarithmic units terminate using the [dB] key. RF levels in linear and logarithmic units are selected from the utilities (see ‘Choice of units’ below). If a value outside the specified range is requested, an error message is displayed and the instrument is automatically set to the end of the range.
(4) You can then adjust the level either in steps using the [Ø],[×] keys or by using the control
knob for continuous adjustment. The default increment/decrement is 1 dB.
(5) You can check the current amount of offset from the reference level by pressing [TOTAL Δ].
This causes the Total Shift Menu to be displayed.
(6) Pressing [Return Value] returns you to the reference level; pressing [Transfer Value] selects
the currently displayed level as the reference level.
(7) Pressing [SIG GEN] returns you to the Sig Gen menu.
output impedance.
Choice of units
Units may be μV, mV, V or dB. Conversion between dB and the voltage units is carried out by pressing the appropriate units key; for example, to change dBm to a voltage unit, press any voltage key for the correct conversion. The choice of Volts EMF, Volts PD and the dB reference is made by using the RF Level Units Selection Menu.
Reverse power protection
Accidental application of power to an individual signal source’s RF OUTPUT socket trips the reverse power protection circuit (RPP) and a menu similar to that shown in Fig. 3-9 below appears with a flashing message.
B3473
Fig. 3-9 RPP tripped
Note that the protection circuit may be activated when a source is set to a high level and its RF OUTPUT socket has no terminating load.
3-18 46882/439
The protection circuit can be reset by pressing the [RPP Reset] key for the appropriate source after having either removed the signal to the source or terminated the RF OUTPUT socket. The display then returns to the menu in use at the time that the RPP was tripped. If [RPP Reset] is pressed with the signal still applied, the RPP will trip again.
The maximum reverse power at the COMBINED RF OUTPUT socket is 0.5 W.

Modulation selection

The carrier from each signal source can be amplitude, frequency or phase modulated from an internal or external source. Additionally pulse modulation is available from an external source. The internal modulation oscillator is capable of generating two tones simultaneously in one modulation channel and has a frequency range of 0.01 Hz to 20 kHz.

Modulation modes

Each signal source has its own independent modulation facilities. The MOD I/O socket on each of the signal sources allows an external modulation signal to be summed with the signals from the internal oscillator. This allows up to three modulations to be available from each source; for example, external FM with a combined internal AM1 and AM2.
Modulation source can be internal or external. If internal, the modulation can be the sum of two signals AM1 + AM2, FM1 + FM2 or ϕM1 + ϕM2 each of which can have its own depth/deviation and modulation frequency.
The common carrier wave can be modulated by two different types of modulation, where one uses an internal source and the other an external source. The internal source may be composed of two signals. Allowed combinations are:
internal AM + external FM ; internal FM + external AM internal AM + external ϕM ; internal ϕM + external AM
Note that pulse modulation may be selected for each signal source in addition to any normal modulation combination.
INDIVIDUAL SOURCE OPERATION

Mode selection

Modulation mode is selected as follows: (1) Press the [UTIL] hard key to display the Utilities Selection Menu 1 (additionally pressing
[Utils Menu 1] if necessary). Then select [Mod’n Mode] to display the Modulation Mode
Selection Menu. This shows the currently selected modulation mode (see Fig. 3-9 below) for
the selected signal source.
Fig. 3-10 Modulation mode selection menu
B3460
46882/439 3-19
LOCAL OPERATION
(2) Use the [Up] and [Down] keys to move the selection box over the required modulation
(3) Press [Select Mode]. The display changes to show your new current modulation mode. (4) Press [SIG GEN] to display the Sig Gen menu which has been modified to show the new
Sig gen screens
Changing the modulation mode by means of the Modulation Mode Selection Menu affects the way in which the Sig Gen screen is presented as follows:
If a single internal modulation mode for example, AM internal has been selected, the [Select Waveform] key is displayed. This is replaced by the [Select Coupling] key if instead, a single external modulation mode for example, FM external has been selected.
If a dual internal modulation mode for example, AM1 + AM2 internal has been selected, the modulation field is divided vertically into two panels, one for each modulation channel as shown in Fig. 3-11 below.
mode. Repeated pressing of the [Down] key will cause the screen to scroll, revealing further selections.
configuration.
B3425
Fig. 3-11 Sig Gen menu with two internal modulation channels
If a dual mixed modulation mode for example, AM1 internal & FM external
has been selected, the modulation field is divided horizontally into two panels, one for each modulation source as shown in Fig. 3-12 below.
B3461
Fig. 3-12 Sig Gen menu with internal and external modulation sources
3-20 46882/439

Internal waveform selection

Having selected an internal modulation mode, you can select the type of waveform as follows: (1) Press [SIG GEN] to show the Sig Gen menu. (2) Press [Select Waveform] to display the Internal Source Waveform Menu. This shows the
currently selected modulation and waveform (see Fig. 3-13 below).
INDIVIDUAL SOURCE OPERATION
B3419
(3) Select between [Sine Wave], [Triangle Wave] and [Square Wave]. The waveform on the
screen changes to show your new waveform selection.
(4) Press [EXIT] to return to the Sig Gen menu.
Modulation source adjustment
You can adjust the phase difference of modulation oscillator channel 2 relative to channel 1 in degrees as follows:
(5) Press the [Mod Src Phase] key to display the Modulation Source Phase Adjustment menu
shown in Fig. 3-14 below. This shows the currently selected phase difference setting for the selected signal source.
Fig. 3-13 Internal source waveform menu
B3418
Fig. 3-14 Modulation source phase adjustment menu
(6) Select the required adjustment control by pressing [Knob Fine], [Knob Medium] or [Knob
Coarse]. These provide adjustments in steps of 0.1°, 1.0° and 3.0° respectively.
46882/439 3-21
LOCAL OPERATION
(7) Press [Phase Diff] and adjust the phase using the control knob. Turn clockwise to advance
the phase and anticlockwise to retard the phase. Note that if you have set the source phase and subsequently adjusted the source frequency or changed the waveform, the menu Phase Difference: value will be blanked. This is because the value will then be indeterminate due to the adjustment or changed waveform.
(8) To establish a reference, the displayed phase shift can be reset to 0.0° by pressing [Reset
Phase].
(9) Press [EXIT] to return to the Sig Gen menu.

External source coupling

Having selected an external modulation mode, you can select the type of external coupling as follows:
(1) Press [SIG GEN] and show the Sig Gen menu for a single modulation mode. (2) Press [Select Coupling] to display the External Source Coupling Menu. This shows the
currently selected modulation and external coupling (see Fig. 3-15 below). The [DCFM Nulling] key appears only during FM external modulation mode with DC coupling.
(3) Select between [Ext AC Coupling], [Ext ALC Coupling] and [Ext DC Coupling]. The screen
(4) Apply a signal to the MOD I/O socket. (5) When Automatic Levelling Control is selected by pressing [Ext ALC Coupling], and the
(6) Press [EXIT] to return to the Sig Gen menu.
DCFM nulling
For a DC-coupled external signal, small frequency offsets can be reduced by using the DCFM nulling facility. Operation is as follows:
(1) With FM External mode previously selected from the Modulation Mode Selection Menu
(2) Connect your ground reference to the MOD I/O socket. (3) Press the [DCFM Nulling] key which is now displayed. * DCFM Nulling * appears during
B3417
Fig. 3-15 External source coupling menu
changes to show your new coupling selection.
error message Err 511: ALC too high or Err:512: ALC too low is displayed, the level must be adjusted. Adjust the signal level until it is within the 0 .75 to 1.25 V RMS ALC range of the source.
press the [Ext DC Coupling] key shown in Fig. 3-15 above.
the nulling process and when it disappears the process is completed.
3-22 46882/439

Modulation ON/OFF

[Mod ON/OFF] switches all modulation ON or OFF and the condition is indicated in the centre of the Sig Gen menu:
Modulation is also controlled by the individual modulation ON/OFF keys. For modulation to appear on the carrier, modulation must be both enabled with the [Mod ON/OFF] key and the individual [AM ON/OFF], [FM ON/OFF], [ individual modulation ON/OFF keys only reduce the modulation to zero, whereas the [Mod ON/OFF] key completely disables the modulation system so that the instrument reverts to a carrier frequency generator.

Amplitude modulation selection

Select amplitude modulation as follows: (1) Press [SIG GEN] to show the Sig Gen menu with the current modulation displayed in the
bottom half of the screen. (2) Press the [AM] soft key if displayed (otherwise the instrument is already in the AM mode). (3) Press[AM Depth]. Enter the modulation depth using the numerical key pad and terminate
with any [ENTER] key. If you exceed the 99.9% modulation limit it is automatically reset to
the maximum allowed value. (4) If the internal modulation is to be the sum of two internal signals, select AM1 + AM2 internal
from the utilities (see ‘Mode selection’ on page 3-19). A typical display is shown in
Fig. 3-16 below. Press the [AM2] key to select the second signal. Press the [AM2 Depth]
key and enter the required modulation depth for the second signal. If you exceed the
(99.9% AM1) modulation depth limit, it is automatically reset to the maximum allowed
value.
INDIVIDUAL SOURCE OPERATION
Modulation DISABLED
ϕ
M ON/OFF] and [Pulse ON/OFF] keys. The
B3425
Fig. 3-16 Sig Gen menu with two modulation channels
(5) Select [AM Mod Freq], enter the modulation frequency and terminate with the [Hz] or [kHz]
key. If you exceed the 20 kHz modulation limit it is automatically reset to the maximum
allowed value. (6) If required, change the waveform from that shown on the display (see ‘Internal waveform
selection’ on page 3-21). (7) Press [
46882/439 3-23
AM ON/OFF] to toggle between the on and off states as shown by the display.
LOCAL OPERATION

Frequency modulation selection

Select frequency modulation as follows: (1) Press [SIG GEN] to show the Sig Gen menu with the current modulation displayed in the
bottom half of the screen. (2) Press the [FM] soft key if displayed (otherwise the instrument is already in the FM mode). (3) Press [FM Devn]. Enter the deviation using the numerical key pad and terminate with the
[Hz] or [kHz] key. If you exceed the 100 kHz deviation limit it is automatically reset to the
maximum al lowed value. (4) If the internal modulation is to be the sum of two signals, select FM1 + FM2 internal from
the utilities (see ‘Mode selection’ on page 3-19). A typical d isp lay is shown in Fig. 3-16
above. Press the [FM2] key to select the second signal. Press the [FM2 Depth] key and
enter the required deviation for the second signal. If you exceed the (100 kHz FM1)
deviation limit, it is automatically reset to the maximum allowed value. (5) Select [FM Mod Freq], enter the modulation frequency and terminate with the [Hz] or [kHz]
key. If you exceed the 20 kHz modulation limit it is automatically reset to the maximum
allowed value. (6) If required, change the waveform from that shown on the display (see ‘Internal waveform
selection’ below). (7) Press [FM ON/OFF] to toggle between the on and off states as shown by the display.

Phase modulation selection

Select phase modulation as follows: (1) Press [SIG GEN] to show the Sig Gen menu with the current modulation displayed in the
bottom half of the screen.
ϕ
(2) Press the [ (3) Press [
[rad] key. If you exceed the 10 rad deviation limit it is automatically reset to the maximum
allowed value. (4) If the internal modulation is to be the sum of two signals, select ϕM1 + ϕM2 internal from
the utilities (see ‘Mode selection’ on page 3-19). A typical d isp lay is shown in Fig. 3-16
above. Press the [
enter the required deviation for the second signal. If you exceed the (10 rad − ϕM1)
deviation limit, it is automatically reset to the maximum allowed value. (5) Select [
key. If you exceed the 20 kHz modulation limit it is automatically reset to the maximum
allowed value. (6) If required, change the waveform from that shown on the display (see ‘Internal waveform
selection’ on page 3-21). (7) Press [
M] soft key if displayed (otherwise the instrument is already in the ϕM mode).
ϕ
M Devn]. Enter the deviation using the numerical key pad and terminate with the
ϕ
M2] key to select the second signal. Press the [ϕM2 Depth] key and
ϕ
M Mod Freq], enter the modulation frequency and terminate with the [Hz] or [kHz]
ϕ
M ON/OFF] to toggle between the on and off states as shown by the display.

Pulse modulation selection

Pulse modulation may be selected in addition to any other normal modulation modes. The source is external from any of the PULSE INPUT sockets. Select pulse modulation as follows:
(1) Press [UTIL] to display the Utilities Selection Menu 1. If the Utilities Selection Menu 2 is
displayed, it will be necessary to press the [Utils Menu 1] key. (2) Select [Mod’n Mode] to display the Modulation Mode Selection Menu. (3) Press the [Pulse Enab/Dis] key to toggle between the ON and OFF states until the display
shows Pulse Mod’n: ENABLED. (4) Press [SIG GEN] to return to the Sig Gen menu.
3-24 46882/439
(5) Press [Pulse ON/OFF] to toggle between the ON and OFF states until the display shows

FSK selection

The instrument accepts logic level inputs to the AUXILIARY PORT connector to produce an FSK modulated output signal from each source. The input data is sampled at 100 kHz and produces a 2- or 4-level shift waveform which is filtered by a 20 kHz Bessel filter and applied to the carrier. Frequency shift keying is selected as follows:
(1) Press [UTIL] to display the Utilities Selection Menu 1. If the Utilities Selection Menu 2 is
(2) Select [Mod’n Mode] to display the Modulation Mode Selection Menu. (3) Use the [Up] and [Down] keys to move the selection box over the required 2FSK or 4FSK
(4) Press [Select Mode]. The display changes to show your new current modulation mode. (5) Press [SIG GEN] to display the Sig Gen menu. This has been modified to show either 2 level
INDIVIDUAL SOURCE OPERATION
Pulse ON. When ON the carrier is controlled by the logic level applied to the PULSE INPUT socket. A logical ‘1’ (a voltage between 3.5 and 5 V) allows carrier output, a logical ‘0’ (a voltage between 0 and 1.0 V) suppresses it. Turning pulse mod OFF effectively applies a logical ‘1’ allowing carrier output.
displayed, it will be necessary to press the [Utils Menu 1] key.
modulation mode.
FSK Ext source or 4 level FSK
Ext source in the modulation field (see Fig. 3-17 below).
B3474
Fig. 3-17 Sig Gen menu with 4FSK selected
(6) Press [FM Devn], enter the required deviation and terminate with the [Hz] or [kHz] key. If
you exceed the 100 kHz deviation limit the entered value is automatically reset to the maximum al lowed value.
(7) If FSK is turned off (either locally with [FM ON/OFF] or globally with [Mod ON/OFF]) no
frequency shift is applied to the carrier.
For information on the use of the AUXILIARY PORT connector for FSK operation see Chapter 2 ‘Auxiliary port connector’ and ‘FSK operation’.
46882/439 3-25
The sweep capability allows the comprehensive testing of systems, since measurements at single points will not necessarily give an overall indication of the performance. The sweep function is specified by the following parameters:
Start frequency
Stop frequency
Size of step
Time per step
The sweep can be operated in single shot or continuous modes with the start command triggered by a key press, an external pulse or GPIB control. Once started, the sweep can be stopped at any time when the display will indicate the current parameter value.

Sweep operation

(1) Press the [SWEEP] key which causes the Sweep Control screen to be displayed. In fixed,
non-sweep, mode the screen is similar to that shown in Fig. 3-18 below. In sweep mode the screen changes similar to that shown in Fig. 3-20.

Sweep

B3426
Fig. 3-18 Sweep control screen in fixed mode
(2) Press [Sweep Mode] to display the Carrier Sweep Mode menu shown in Fig. 3-19 below.
B3427
Fig. 3-19 Carrier sweep mode menu
46882/439 3-27
LOCAL OPERATION
(3) Select the A, B or C source for sweeping by pressing the appropriate [A Swept Source],
(4) Select the sweep mode between single shot and continuous sweeping by pressing the
(5) For external triggering press [Ext Trig Off] to inhibit the external trigger or press one of the
[Ext Trig Start]
[Ext Trig StrtStop]
[Ext Trig Step]
(6) Pressing [No Swept Source] disables sweep mode. (7) If no source has been selected for sweeping, pressing [EXIT] will return you to the Carrier
[B Swept Source] or [C Swept Source] key.
[Sweep] key which toggles between [Single Sweep] and [Cont Sweep].
following keys to select the appropriate trigger mode:
The first trigger input causes the carrier sweep to commence sweeping. Any other trigger inputs whilst sweeping are ignored. Only at the end of each sweep is the trigger latch reset ready for the next input.
The first trigger input starts the carrier sweep and the following trigger input pauses it, so that the user can investigate a particular point of interest. The next trigger input continues the sweep from where it was paused. At the start of each sweep the trigger latch is reset ready for the next input.
Each trigger input steps the sweep on by one frequency step. The trigger
latch is reset after each step ready for the next step.
Sweep Mode Menu. Otherwise, the Sweep Control screen will be displayed.
Sweep control
(8) The Sweep Control screen displayed is similar to that shown in Fig. 3-20 below. This is used
to perform the sweeping operation.
B3428
Fig. 3-20 Sweep control screen in sweep mode (B and C sources coupled to A source)
(9) Enter the sweep start and stop frequencies using the [Start Freq] and [Stop Freq] keys. (10) Press [Step Size] and enter the step size in the range 1 Hz to the instrument maxi mum
frequency, to a resolution of 1 Hz. (11) Press [Step Time] and enter the step time in the range 50 ms to 10 s to a resolution of 1 ms. (12) To start the sweep press [Start Sweep]. The key changes its function to [Stop Sweep] and
Sweep Status changes from WAITING FOR TRIGGER to SWEEPING. The displayed Sweep
Freq changes to show the progress of the sweep.
(13) The sweep can be stopped at any time by pressing [Stop Sweep]. This causes the key
function to change to [Continue Sweep] and Sweep Status changes to PAUSED.
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SWEEP
(14) Whilst the sweep is paused you can adjust the frequency by selecting [Sweep Freq] then
using the control knob to look at a particular frequency of interest. Pressing [Transfer] followed by [Continue Sweep] causes the sweep to continue from your adjusted frequency. Otherwise simply pressing [Continue Sweep] restarts the sweep from where it was paused. Pressing [Reset Sweep] discontinues the sweep and resets it to the start frequency.
(15) At the end of a single sweep, the stop frequency is shown and the key function changes to
[Start Sweep] with SWEEP COMPLETE displayed. For continuous sweep, the sweep automatically recommences from the start frequency.
(16) To change the sweep mode, press the [Sweep Mode] key which returns you to the Carrier
Sweep Mode menu.
46882/439 3-29

Utility menu selection

Pressing the [UTIL] key gains access to the utilities options from two primary menus, Utilities Selection Menu 1 and Utilities Selection Menu 2. When a selection is made from either of these
menus and [UTIL] is subsequently pressed, the primary menu is re-displayed. However, if instead a selection is made and then one of the other hard keys for example, [MEM] is pressed, pressing [UTIL] subsequently once return to the sub-menu, pressing it again returns to the primary menu. This provides an operating short-cut in that it allows you to re-access a sub-menu without first having to go again through the primary menu.

Selection menu 1

Utilities

The display for Utilities Selection Menu 1 is shown in Fig. 3-21 below.
To obtain Utilities Selection Menu 2 from the menu, select [Utils Menu 2].

Display adjustment (menu 1)

You can set the display contrast and brightness to suit your individual preferences using this utility. The setting can then be saved for automatic recall whenever the instrument is switched on. Proceed as follows:
(1) Select [Display Adjust] to call up the Display Adjustment Utility shown in Fig. 3-22 below.
Fig. 3-21 Utilities selection menu 1
B3453
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LOCAL OPERATION
(2) Set the required brightness by pressing [Dim], [Medium] or [Bright]. You can then adjust
(3) Once adjusted, the display setting can be stored in the non-volatile memory by pressing
(4) Press [EXIT] to return to the Utilities Selection Menu 1.
Fig. 3-22 Display adjustment utility
the contrast by means of the control knob.
[Save LCD Setting]. The setting will be subsequently recalled on power-up.
B3454

Frequency standard selection (menu 1)

This utility enables you to select a 10 MHz output as a standard for use with associated equipment. It also enables you to select a standard (either external or internal) for use by the instrument. When an external standard is selected, the internal TCXO is locked to the external standard using a phase locked loop. For a 10 MHz standard, the menu allows you to select between direct and indirect. When direct is selected the internal standard for the RF trays is provided directly from the external standard. When indirect is selected this standard is provided from the TCXO locked to the external standard. Frequency standard selection is as follows:
(1) Select [Freq Standard] to display the Frequency Standard Selection Menu shown in
Fig. 3-23 below. This shows the currently selected standard.
B3455
Fig. 3-23 Frequency standard selection menu
(2) Select the internal standard for the instrument by pressing [10 MHz Int]. (3) To provide an externally generated 1 or 10 MHz standard for the instrument, connect the
signal to the rear-panel EXT STD I/P socket. Then choose one of the three external
standards [10 MHz Ext Dir], [1 MHz Ext Ind] or [10 MHz Ext Ind]. You should choose
3-32 46882/439
[10 MHz Ext Dir] if your provided 10 MHz standard is better than that fitted in the instrument.
(4) To obtain an internally generated 10 MHz standard from the instrument’s INT STD O/P
socket, select [10 MHz Int Out].
(5) Press [EXIT] to return to the Utilities Selection Menu 1.

Carrier phase adjustment (menu 1)

You can adjust the phase offset of the carrier with respect to its current phase in degrees as follows:
(1) Press [Carrier Phase] to display the Carrier Phase Adjustment Utility shown in Fig. 3-24
below. This shows the currently selected phase offset for the selected signal source.
UTILITIES
Fig. 3-24 Carrier phase adjustment utility
(2) Select the required adjustment control by pressing [Knob Fine], [Knob Medium] or [Knob
Coarse]. These provide adjustments in steps of 0.09°, 0.9° and 2.7° respectively.
(3) Press [Phase Shift] and adjust the carrier phase using the control knob. Turn clockwise to
advance the phase and anticlockwise to retard the phase. Note that if you have set the carrier phase and subsequently adjusted the carrier frequency, the menu Phase Shift: value will be blanked. This is because the value will then be indeterminate due to the adjustment.
(4) To establish a reference the displayed phase shift can be reset to 0.00° by pressing [Reset
Shift]. But note that this do es not reset the actual phase shift, only the displayed value is reset to provide a new reference.
(5) Press [EXIT] to return to the Utilities Selection Menu 1.

RF level units selection (menu 1)

RF output level units may be changed as follows: (1) Press [RF Level Units] to display the RF Level Units Selection Menu which shows the
current selection (see Fig. 3-25 below).
B3456
46882/439 3-33
LOCAL OPERATION
(2) Select between linear and logarithmic units in EMF or PD. Logarithmic units may be
(3) Press [EXIT] to return to the Utilities Selection Menu 1.
B3457
Fig. 3-25 RF level units selection menu
referred to volts (dBV), millivolts (dBmV), microvolts (dBμV) or to 1 millivolt into 50 Ω
(dBm).

50 Ω /75 Ω impedance selection (menu 1)

The performance specification of each signal source assumes operation into 50 Ω loads. By means of this menu in association with a 75 Ω adapter (see data sheet in Chapter 1) you can select operation into 75 Ω loads whilst maintaining correct voltage calibration. It also enables the reverse power protection circuit to function correctly. But note that in the event of an overload the RPP will function but the adapter will NOT be protected. Proceed as follows:
(1) Press [50
below.
Ω/75Ω
Cal] to display the 50 Ohm/75 Ohm Calibration Menu shown in Fig. 3-26
B3458
Fig. 3-26 50 ohm/75 ohm calibration menu
(2) Press [50
Ω/75Ω
Cal] which toggles between 50 Ohm Calibration and 75 Ohm Calibration as shown by the screen. Note that all RF OUTPUT sockets, including the combiner’s, will change calibration.
(3) For 75 Ω operation connect a 50 Ω/75 Ω adapter to the front-panel RF OUTPUT socket for
each appropriate signal source. Whenever the impedance is changed, the value of the displayed level is adjusted (by 5.7 dB) to the level at the output from the adapter.
(4) Press [EXIT] to return to the Utilities Selection Menu 1.
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Power-up options (menu 1)

The instrument can power-up in one of two states; with the factory settings or with the settings of your choice stored in one of the full memory locations. Selection is made as follows:
(1) Press [Power Up Options] to display the Power Up Options Menu shown in Fig. 3-27 below.
This shows the currently selected power-up choice.
UTILITIES
B3459
(2) Press [Factory Power Up] to select the factory power-up settings (these are listed in
Table 3-1 below). Otherwise press [Memory Power Up] to store the current settings as your selected power-up state.
(3) Press [EXIT] to return to the Utilities Selection Menu 1.

Default settings

The instrument is reset to the factory default settings in the following cases: (1) At power-up to factory default settings.
(2) Following execution of the *RST comma nd. (3) When [Factory Recall] is pressed on the Memory Recall Menu. The default settings are shown in Table 3-1.
Fig. 3-27 Power up options menu
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LOCAL OPERATION
Source selected Source A Carrier frequency :
Step : RF level
Step : Modulation mode Internal FM, modulation disabled Modulations : FM1 : Deviation: 0 Hz, OFF
FM2 : Deviation: 0 Hz, OFF
AM1 : Deviation: 0%, OFF
AM2 : Deviation: 0%, OFF
Pulse : OFF
Modulation steps : Mod frequency steps : 10 Hz Carrier sweep
Freq mode : Mode : Ext trigger : Start : Stop : Step size : Time :
Table 3-1 Instrument default settings
(Maximum available) 2.4 GHz 1 kHz
137 dBm 1 dB Status: ON
: Internal source, frequency: 1 kHz, sine
: Internal source, frequency: 400 Hz, sine ΦM1 : Deviation: 0 rad, OFF
: Internal source, frequency: 1 kHz, sine ΦM2 : Deviation: 0 rad, OFF
: Internal source, frequency: 400 Hz, sine
: Internal source, frequency: 1 kHz, sine
: Internal source, frequency: 400 Hz, sine
: ΔFM 1 kHz, ΔΦΜ 0.1 rad, ΔΑΜ 1%
Fixed Single sweep Off 10 kHz (Maximum available) 1 kHz 50 ms

Modulation mode selection (menu 1)

Modulation mode is selected by pressing [Mod’n Mode] to display the Modulation Mode Selection Menu shown in Fig. 3-28 below. Using the menu is explained under ‘Modulation mode selection’
above.
Fig. 3-28 Modulation mode selection menu
B3460
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Remote control selection (menu 1)

The remote mode of operation is selected as follows: (1) Select [Remote Control] to display the Remote Control Utility. This shows the currently
selected remote mode (see Fig. 3-29 below).
Fig. 3-29 Remote control utility
UTILITIES
B3475
(2) Press [GPIB/RS232] to toggle between GPIB and RS232.
GPIB mode
(3) Press [GPIB Address] and enter the address, which must be unique on the system to the
instrument and within the range 0 to 30.
RS-232 mode
(3) Press [Data Bits] to toggle between 7 and 8 data bits. (4) Press [Stop Bits] to toggle between 1 and 2 stop bits. (5) Press [Parity] to cycle through the selections None, Odd, Even. (6) Press [Hardware Hndshk] and [XON/XOFF Hndshk] to select any combination between
both OFF to both ON.
(7) Press [Baud Rate] and set the baud rate in the range 300 to 9600 bit/s. But note that if the
entered value is not one of the following standard settings, the nex t h ig her value will be selected by default.
300 600 1200 2400 4800 9600
(8) Press [EXIT] to return to the Utilities Selection Menu 1.

Background error reporting (menu 1)

Background errors are generated due to an incorrect operating condition within the instrument. These error messages are generated automatically to warn the operator. Although there is room only to display one message in the error message field of the displays, this utility enables a complete list of the current background errors to be shown. Proceed as follows:
(1) Press [Backg’nd Errors] which causes the Current Background Errors display similar to that
46882/439 3-37
in Fig. 3-30 below to be shown. The errors are shown in priority order.
LOCAL OPERATION
(2) Where there are more background errors than can be displayed on one screen page, the [Next
(3) Press [EXIT] to return to the Utilities Selection Menu 1.
B3476
Fig. 3-30 Current background errors display (showing example errors)
Page] and [Previous Page] soft keys will be displayed to enable more than one page of
errors to be viewed.

Protection locking and unlocking (menu 1)

To prevent accidental interference with the contents of internal memories, internal data is protected by secure key sequences. There are two levels of protection. The most secure, Level 2, is used for memory erasure, elapsed time reporting and for servicing purposes such as altering the calibration data of the instrument. Level 1 protection is used for display blanking and memory protection.
The lock and unlock utility is selected as follows: (1) Select [Lock & Unlock] to display the Lock & Unlock Utility. When Level 1 and Level 2 are
both locked the display will be similar to Fig. 3-31 below.
Fig. 3-31 Lock and unlock utility (during password entry)
B3477
(2) To unlock to Level 1 press [Unlock Level 1] and enter a 4-digit password (the default is
1234). As each digit is entered an asterisk is displayed. Terminate with [ENTER].
(3) To unlock to Level 2 press [Unlock Level 2] and enter a 6-digit password (the default is
123456). As each digit is entered an asterisk is displayed. Terminate with [ENTER].
(4) When successful, UNLOCKED is displayed on the screen against the appropriate level and
the [Unlock Level 1] or [Unlock Level 2] key is blanked. If the entered password is not recognized by the instrument the password will have been changed by operating personnel.
(5) To lock the instrument, press the appropriate [Lock Level 1] or [Lock Level 2] key.
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(6) Press [EXIT] to return to the Utilities Selection Menu 1.
If you have lost or forgotten the password contact our Customer Services or your nearest agent (for addresses see inside rear cover). You will be required to give the instrument’s serial number.

Selection menu 2

Press the [Utils Menu 2] on the Utilities Selection Menu 1 to obtain the display for Utilities Selection Menu 2 as shown in Fig. 3-32 below. Some of the items on this menu are intended for
use in servicing and are described in the maintenance manual. As a result, some of these keys appear only when unlocked to the appropriate Level.
UTILITIES
To obtain Utilities Selection Menu 1 from the menu, select [Utils Menu 1].

Software information (menu 2)

You can obtain a description of the instrument’s software by pressing [Software Status] which causes Fig. 3-33 below to be displayed. This shows the software version and date as well the EPROM part number.
Fig. 3-32 Utilities selection menu 2
B3478
B5013
Fig. 3-33 Software status display
(1) Press [EXIT] to return to the Utilities Selection Menu 2.
46882/439 3-39
LOCAL OPERATION

Hardware information (menu 2)

You can obtain a description of the instrument’s hardware by pressing [Hardware Status] which causes Fig. 3-34 below to be displayed. This shows the instrument type and serial number as well as options fitted.
Fig. 3-34 Hardware status display
B3479
(1) Press [EXIT] to return to the Utilities Selection Menu 2.

Patent information (menu 2)

To obtain the more important patent information, press [Patent Info] which causes Fig. 3-35 below to be displayed.
(1) For a full list of patents refer to ‘Patent protection’ in the Preface. (2) Press [EXIT] to return to the Utilities Selection Menu 2.
Fig. 3-35 Patent information display
B3480

Display blanking (menu 2)

This facility is used to prevent sensitive data from being displayed. It allows various parts of the display to be replaced by a series of dashes so that values entered by the user or recalled from the
3-40 46882/439
memory will not be visible.
UTILITIES
B3481
Fig. 3-36 Display blanking utility
(1) Unlock the protection to Level 1 by means of the Lock & Unlock Utility (menu 1). (2) Press [Display Blanking] which causes the screen shown in Fig. 3-36 above to be displayed. (3) To blank the screen press the [Blanking ON/OFF] key which toggles between the on and off
states.
(4) Press the [SIG GEN] key to display the main screen. Here it can be seen that the main
parameters are blanked and replaced by dashes. This also applies to the parameters displayed on the Sweep Control screen.
(5) Press [EXIT] to return to the Utilities Selection Menu 2.

Latch access utility (menu 2)

This utility is intended for use as a diagnostic aid by allowing data to be sent to latches within the instrument. For further information consult the maintenance manual. The menu is shown in Fig. 3-37 below.

Elapsed time (menu 2)

The elapsed time facility displays the total number of operating hours as well as the number of elapsed operating hours since the last reset by the [Reset Elapsed] key. This facility can be used to assess the instrument’s operational reliability and utilization. To use this facility the instrument must be unlocked to Level 2. The screen is shown in Fig. 3-38 below.
Fig. 3-37 Latch access utility
B3530
46882/439 3-41
LOCAL OPERATION

RPP trip count utility (menu 2)

This utility lists the number of times each of the fitted sources has tripped. The screen is shown in Fig. 3-39 below.
Fig. 3-38 Elapsed time utility
B3516

Display test utility (menu 2)

This utility provides a simple test of the display. The screen is shown in Fig. 3-40 below.
Fig. 3-39 RPP trip count utility
Fig. 3-40 Display test utility
B3526
B3527
3-42 46882/439

Key/knob tests (menu 2)

In this utility the user is invited to operate the keys and control knob whilst checking the reaction of the instrument. The screen is shown in Fig. 3-41 below.
Fig. 3-41 Keyboard/knob test utility
UTILITIES
B3528

Calibration utility (menu 2)

This menu shows when each individual item was last adjusted and enables you to enter the date of the current adjustment. The instrument must be unlocked to Level 2 to use this utility. Full d etails regarding calibration can be found in the maintenance manual. The first page of the menu is shown in Fig. 3-42 below.
Fig. 3-42 Calibration menu
B4981
46882/439 3-43

Memory stores

There are three types of store: carrier, full and RAM. Both carrier and full stores are non-volatile. The contents of the RAM store are lost when the instrument is switched off.
Each type of store holds the data for all fitted sources.
Carrier store
The non-volatile carrier frequency store has 100 locations numbered 0 to 99 for the storage of carrier frequency only. This store can be used to apply a set of test conditions to a range of frequencies. For example, if you wish to use the same modulation at a variety of frequencies you can use the carrier store to set the instrument to each of the frequencies in turn. When a carrier store is used it will only replace the current carrier frequency all the other settings will remain unchanged.

Memory

Full store
The non-volatile full store has 100 locations numbered 0 to 99 for the storage of instrument settings. This store is used to store those parameters which currently affect the RF output; carrier frequency, RF level, modulations in use, on/off and source information and the two modulation oscillator frequencies in use.
A full store contains the following information: Carrier frequency setting
Carrier frequency step size RF level setting RF level step size All modulation settings All modulation step sizes Modulation mode and status The active modulation frequencies The modulation frequency step size All sweep settings
RAM store
The volatile RAM store has locations numbered from 0 to 99 for the full storage of instrument settings. The parameters stored are the same as those for the full store. However, the RAM store has no long-term wear-out mechanism and is therefore recommended for use in ATE programs where all the settings to be used in a test sequence are initially declared and then recalled. This results in a reduction of the GPIB/RS-232 overhead.
46882/439 3-45
LOCAL OPERATION

Storing data

Select the memory store function as follows: (1) Press the [MEM] hard key and then, if necessary, press the [Store/Recall] soft key to display
the Memory Store Menu shown in Fig. 3-43 below.
Fig. 3-43 Memory store menu
B3482
(2) To store data, press the [Full Store], [Carrier Store] or [RAM Store] key for the type of store
required, then enter the store location via the numerical key pad and terminate with [ENTER].
Note that memory erasure requires unlocking to Level 2 (see ‘Protection locking and unlocking’ on page 3-38).

Memory protection

Memory stores may be protected against accidental overwriting of the contents.
Memory protection summary
(1) To see which store locations are protected (or unprotected), press the [Memory Protect] key.
If the instrument is in the protection locked state, the Memory Write Protection Summary shown in Fig. 3-44 below is displayed. Otherwise Fig. 3-45 below is shown.
B3484
Fig. 3-44 Memory write protection summary
(2) From the summary, select the type of memory stores to be displayed by selecting between
[Full Stores], [Carrier Stores] and [RAM Stores]. An unprotected store is indicated by a dash (), a protected store is indicated by the letter p.
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(3) Press [EXIT] to return to the Memory Store Menu.
Memory protection menu
(4) To change the write protection, the instrument must be unlocked to Level 1 (see ‘Protection
locking and unlocking’ on page 3-38). Subsequently pressing [ Memory Write Protection Menu similar to that shown in Fig. 3-45 below to be displayed.
MEMORY
Memory Protect] causes the
B3483
(5) Select the type of memory stores to be changed by selecting between [Full Stores], [Carrier
(6) To change the protection for a memory block enter the [Block Start] and [Block Stop]
(7) Select [Protect] or [Unprot.] as required. This action is acknowledged by the message
(8) Press [EXIT] to return to the Memory Store Menu. Note that at power-on the volatile RAM stores are unprotected to allow immediate use.

Memory recall

There are three types of recall: carrier, full and RAM. Both carrier and full stores are non-volatile. The contents of the RAM store are lost when the instrument is switched off.
Carrier recall
The non-volatile carrier frequency store has 100 locations numbered 0 to 99 for carrier frequency only. These can be recalled and used in conjunction with full recall to apply a set of test conditions to a range of frequencies.
Fig. 3-45 Memory write protection menu
Stores] and [RAM Stores]. An unprotected store is indicated by a dash (), a protected store
is indicated by the letter p.
numbers. For a single store make both numbers the same.
** Protected ** or ** Unprotected ** appearing respectively.
Full recall
The non-volatile store has 100 locations numbered 0 to 99 for the storage of instrument settings. These stores may be recalled and used to reset the instrument’s parameters to those which affect the RF output: carrier frequency, RF level, modulations in use, on/off and source information and the two modulation oscillator frequencies in use.
RAM recall
The volatile RAM store has 100 locations numbered 0 to 99 for the full storage of instrument settings. The parameters that are recalled are the same as those for full recall.
46882/439 3-47
LOCAL OPERATION

Recalling data

Select the memory recall function as follows: (1) Press the [MEM] hard key and then, if necessary, press the [Store/Recall] soft key to display
the Memory Recall Menu shown in Fig. 3-46 below.
Fig. 3-46 Memory recall menu
B3485
(2) To recall data, press the [Full Store], [Carrier Store] or [RAM Store] key for the type of
recall required, then enter the store location via the numerical key pad and terminate with [ENTER].
(3) Pressing [Memory Protect] causes a Memory Write Protection screen to be displayed. For
details of displaying the stores and changing their protection states see ‘Memory protection’ on page 3-46.
(4) Press [Fa
ctory Recall] to set the instrument to the factory settings (th ese are listed in
Table 3-1 above).
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Error handling

Error messages are divided into four groups:

Error messages

(1) Background errors (2) Foreground errors (3) GPIB errors (4) Fatal errors
Background errors:
These are generated due to an incorrect operating condition within the instrument. These errors are generated automatically to warn the operator. For example if the reverse power protection circuit should trip the message: Err 500: RPP tripped will be displayed on the main screen. Background errors are listed in Table 3-2. Only one error will be displayed, that with the highest priority. To obtain a full list of errors occurring on your instrument in priority order, select
[Backg’nd Errors] from the Utilities Selection Menu 1. This causes the Current Background Errors screen to be displayed (see Fig. 3-30). Select [Next Page] if the list is continued on a
subsequent page.
Foreground errors:
These are typically generated when an entered parameter value is outside the valid range or for some other invalid operation. For example trying to set the carrier frequency above or below the specified range will display the following message Err 100: Carrier limit on the screen. The foreground errors are cleared upon function selection or by re-entering the parameter correctly. Foreground errors are listed in Table 3-3.
represent a condition of the instrument. generally caused by the user. generated by incorrect programming. caused by failure associated with the main RAM or the
PROM. These errors may or may not be displayed according to the severity of the failure or corruption.
Error message priority:
A background error has a priority bit set which is used to determine which message needs to be displayed. A foreground error will temporarily overwrite the background error if currently displayed, but will return to displaying that error once the foreground error has been cleared.
GPIB errors
When an error occurs the error number is put into the error queue and the error message is displayed. Clearing the error message from the screen does not clear the error queue, which is only cleared by the GPIB command ERROR? query, which returns the error at the head of the queue, or by the *CLS command which clears the whole error queue. GPIB errors are listed in Table 3-4.
The queue holds a maximum of 64 error message error numbers. If an error occurs while the queue is full the last error number is replaced with 399 to indicate that the queue is full. The ERROR? query returns a value of 399 for queue full and 0 for queue empty.
When an error number is written into the queue, a bit (<erb>) in the status byte register is set, and an appropriate bit in the standard event register is also set (one of <cme>, <exe>, <dde> or <qye>). These errors will also generate SRQ if the relevant bit in the status register is set. Many background errors are also reported in the Hardware and Coupling Status Registers.
46882/439 3-49
LOCAL OPERATION
Source-specific errors
Where it is necessary to identify the signal source causing an error, the error message number has 1000, 2000 or 3000 added to it for the A, B and C sources respectively. Thus error number 2500 indicates that the B source has tripped the reverse power protection circuit.
Table 3-2 Background errors (500599) in priority order
591 ftl Main PROM faulty 590 ftl Main RAM faulty
500 dde RPP tripped 501 dde Fractional-N loop low 502 dde Fractional-N loop high 503 dde Ext standard missing 504 dde External std frequency low 505 dde External std frequency high 506 dde VCXO loop low 507 dde VCXO loop high 508 dde Amplitude mod unleveled 509 dde Output unleveled 510 dde High power amplifier failed 511 dde ALC too high 512 dde ALC too low 513 dde DSP not responding
549 exe RF level uncalibrated 550 exe RF level limited by AM 551 exe AM2 limited by AM1 552 exe FM2 limited by FM1 553 exe ΦM2 limited by ΦM1 554 555 556 557 exe Carrier limited by coupling 558 exe Offset limited by harmonic 559 exe Offset limited by sub-harm
560 exe Harmonic limited by offset 561 exe Sub-harm limited by offset
( = Source-specific)
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ERROR MESSAGES
Table 3-3 Foreground errors (0399)
0 dde No error 1 dde EEPROM checksum 2 dde Pad cal checksum 3 dde RF cal checksum 4 dde Freq std checksum 5 dde Synthesizer cal checksum 6 dde Mod ref checksum 7 dde Mod offset checksum 8 dde Mod amp checksum 9 dde ALC cal checksum 10 dde FM cal factor checksum 11 dde FM tracking checksum 12 dde ΦM cal factor checksum 13 dde System cal checksum 14 dde AM cal checksum 15 dde Store checksum 16 dde Image checksum 17 dde EEPROM unreliable 20 dde Frac-N out of lock at <freq> 21 dde VCO cal fail at <freq> 22 dde VTF tune cal fail at <freq> 23 dde FM tracking cal fail at <freq> 24 dde Local EEPROM write 51 dde Keyboard buffer overflow 52 dde Display buffer overflow 53 dde Display missing 62 dde Source not fitted 100 exe Carrier limit 101 exe Carrier step limit ‡ 102 exe RF level limit 103 exe RF level step limit 104 exe Invalid modulation mode 105 exe AM limit 106 exe AM2 limit 107 exe AM step limit ‡ 108 exe AM2 step limit 109 exe FM limit 110 exe FM2 limit 111 exe FM step limit ‡ 112 exe FM2 step limit 113 exe ΦM limit 114 exe ΦM2 limit 115 exe ΦM step limit 116 exe ΦM2 step limit 117 exe Memory limit 118 exe AM mod freq limit 119 exe AM mod step limit 120 exe AM2 mod freq limit 121 exe AM2 mod step limit 122 exe FM mod freq limit 123 exe FM mod step limit 124 exe FM2 mod freq limit 125 exe FM2 mod step limit 126 exe ΦM mod freq limit 127 exe ΦM mod step limit 128 exe ΦM2 mod freq limit 129 exe ΦM2 mod step limit 130 exe Return/Transfer not allowed 131 exe Util limit 132 exe Start freq limit 133 exe Stop freq limit 134 exe Sweep time limit 135 exe Sweep mode disabled 136 exe Carrier phase limit 137 exe AM phase limit 138 exe FM phase limit 139 exe ΦM phase limit 140 exe Memory store limit 141 exe Memory recall limit 142 exe Display blanking limit 143 exe GPIB address limit 144 exe Latch address limit 145 exe Latch data limit 146 exe Freq std carrier limit 147 exe Freq std course adj limit 148 exe Freq std fine adj limit 149 exe Mod ref adj limit 170 exe Util not available 171 exe Entry outside limits 172 exe Data out of range 173 exe Units not valid 174 exe Unlev fact limited by FM fact 175 exe Invalid baud rate 176 exe Data overrun 177 exe Data parity 178 exe Data framing 179 exe Break in data
continued
46882/439 3-51
LOCAL OPERATION
Foreground errors (0399) - continued
180 exe Transmit buffer full 181 exe Receiver not enabled 182 exe Protected utility − Level 1 183 exe Protected utility − Level 2 184 185 exe This store is Read Only 186 187 188 exe Receive buffer full 189 exe Pulse has been disabled 190 exe No attenuator fitted 191 exe No high power amp fitted
192 193 exe Ext DCFM mod mode required
195 exe Invalid coupling mode
196 exe Invalid in application mode 198 exe Atten lock disabled 199 exe Atten lock not allowed 200 exe Atten lock not allowed 201 exe Atten lock not allowed 202 exe No pulse with application 398 399 exe Error queue full
( = Source-specific)
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ERROR MESSAGES
Table 3-4 GPIB errors (400499)
400 cme Syntax error 401 cme Unrecognized mnemonic 402 cme Numeric syntax 403 cme Data expected 404 cme Illegal data 405 cme Too much data 406 cme Incorrect data type 407 cme Unrecognized character data 408 cme Character data not unique 409 cme Block definition 410 cme Block size 411 cme Missing quote 412 cme Terminator expected 413 cme Invalid unit 414 cme Unit not expected 415 cme No header match found 416 cme Header not unique 417 cme Illegal star command 418 cme Sub-command not allowed 419 cme Action not allowed with header 420 cme Query not allowed with header 421 cme Parser decode
450 qye Query INTERRUPTED 451 qye Query UNTERMINATED 452 qye Query DEADLOCK 453 qye Query lost after arbitrary char
46882/439 3-53
Chapter 4

SETUP

Contents
Summary........................................................................................................................................4-2
Setup menu selection .....................................................................................................................4-2
Combiner setup
Com
biner selection ........................................................................................................................4-3
External source
Coupling
Frequency and level coupling
Applications
Applications sum Applications selection Am
Receiver two-tone intermodulation application
Receiver selectivity application
........................................................................................................................................4-5
Coupling selection
plifier intermodulation distortion application ..........................................................................4-8
Two-tone test Three-tone test Procedure
Procedure
Procedure
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mary ................................................................................................................... 4-7
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List of figures
Fig. 4-1 Setup menu (shown for three sources fitted)................................................................. 4-2
Fig. 4-2 Combiner setup menu....................................................................................................4-3
Fig. 4-3 Com Fig. 4-4 Frequency and level coupling m Fig. 4-5 Applications selection m Fig. 4-6 Interm Fig. 4-7 Interm Fig. 4-8 Interm Fig. 4-9 Interm
g. 4-10 Intermod. distortion test on amplifier: modulation setup menu, ϕM selected ............. 4-10
Fi Fig. 4-11 Interm Fig. 4-12 Setup m Fig. 4-13 Two-tone interm Fig. 4-14 Two-tone interm Fig. 4-15 Two-tone interm Fig. 4-16 Two-tone interm Fig. 4-17 Two-tone interm Fig. 4-18 Two-tone interm Fig. 4-19 Setup m Fig. 4-20 Receiver selectivity block diagram Fig. 4-21 Receiver selectivity spectral diagram Fig. 4-22 Receiver selectivity: application accepted Fig. 4-23 Receiver selectivity: receiver m Fig. 4-24 Receiver selectivity: interferer m Fig. 4-25 Receiver selectivity: source sum Fig. 4-26 Setup m
biner setup menu, showing link between C source and combiner......................... 4-4
enu..............................................................................4-5
enu (shown for three sources fitted) ......................................4-7
od. distortion test on amplifier block diagram....................................................4-8
od. distortion test on amplifier spectral diagram.................................................4-9
od. distortion test on amplifier: 2-tone selected.................................................. 4-9
od. distortion test on amplifier: 3-tone selected................................................ 4-10
od. distortion test on amplifier: Source summary screen..................................4-11
enu in application mode.................................................................................4-11
od. measurement on receiver block diagram....................................4-12
od. measurement on receiver: spectral diagram................................4-12
od. measurement on receiver: application accepted.........................4-13
od. measurement on receiver: modulation setup menu.....................4-13
od. measurement on receiver: interferer mod setup menu................4-14
od. measurement on receiver: source summary................................4-14
enu in application mode.................................................................................4-15
.............................................................................4-15
..........................................................................4-16
...................................................................4-16
odulation setup menu................................................4-17
odulation setup menu..............................................4-17
mary.........................................................................4-18
enu in application mode.................................................................................4-18
46882/439 4-1
SETUP

Summary

The setup menus are used to route the outputs from the signal sources to either their individual RF OUTPUT sockets or, via the combiner, to the COMBINER RF OUTPUT socket and additionally allow the sources to be coupled together by a mathematical formula in both frequency and level. The routing is set using the combiner setup facility and the coupling parameters are enabled and set using the coupling setup facility.
The applications facility allows the user to select one of a number of common test configurations, such as intermodulation testing, for two or three signal sources. When an application is selected the most appropriate signal routing is automatically chosen and the required coupling controls enabled. Control parameters are then redefined in terms of the measurement being performed to minimize the number of parameter entries required. For example for intermodulation testing with equal amplitude sources, only one RF level control is provided and this automatically sets the level of all of the sources. Control parameters are described in terms which are relevant to the measurement being performed.

Setup menu selection

Pressing the [SETUP] key gains access to the Setup Menu similar to that shown in Fig. 4-1 below.
B3411
Fig. 4-1 Setup menu (shown for three sources fitted)
The [Appl’n Menu] key accesses the Applications Selection Menu which enables you to select one of the three predefined applications. The [Combiner Setup] key accesses the Combiner Setup Menu which enables you to connect the signal sources in any combination to the combiner. The combined signal is then available at the COMBINED RF OUTPUT socket. [Coupling Setup] accesses the Frequency and Level Coupling menu which enables you to couple the B and C sources to the A source. These sources can then track the A source by means of a level offset and a frequency and harmonic offset.
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This facility allows the user to route an individual signal source (A, B or C) to either its designated separate RF OUTPUT connector or through the combiner to the COMBINED RF OUTPUT connector. The current routing of the signal sources is always indicated by the source field at the bottom of the display. If the sources are all routed to their separate connectors the combiner panel
shows
not used.

Combiner selection

Select the required signal source combiner configuration as follows: (1) On the Setup Menu press [Combiner Setup] to display the Comb iner Setup Menu. This
shows a graphical display of the current combiner setup similar to Fig. 4-2 below.

Combiner setup

B3412
Fig. 4-2 Combiner setup menu
∑]
(2) Pressing the [O/P /
its own RF OUTPUT connector (shown by O/P on the display) or, via the combiner, to the COMBINED RF OUTPUT connector (shown by configuration. As shown by the display, the EXT I/P socket is permanently connected to the combiner. But note that switching the C source to the combiner requires you to configure a rear-panel link (see ‘External source’ below).
(3) At each change in configuration the A, B and C source panels and the combined output
panel at the bottom of the display change to show the new destinations. These settings are repeated on all menus.
(4) Pressing the [Indep’nt/Combiner] key switches between the current configuration having a
combiner output and all sources having independent outputs. This provides a convenient way to restore the sources to normal, independent operation.
(5) Selecting [EXIT] returns you to the Setup Menu.
key for a particular source toggles between connecting the source to
). Use these keys to select your required
46882/439 4-3
SETUP
External source
Provision is made on the rear panel for connecting an external signal generator to the combiner via the EXT I/P connector.
For a generator fitted with three internal sources an additional connector, INT O/P, is fitted. The EXT I/P and INT O/P sockets effectively interrupt the C output to the combiner. To route the C source output to the combiner the two connectors are linked by the supplied coaxial jumper lead as shown in Fig. 4-3 below. To use an external source, remove the coaxial jumper lead using an SMA torque spanner and connect the external signal to the EXT I/P connector as shown in Fig. 4-2 above. When unused, always terminate the INT O/P connector by the attached 50 Ω load to prevent signal radiation from the C source.
B3413
Fig. 4-3 Combiner setup menu, showing link between C source and combiner
For generators fitted with only two sources the INT O/P connector is not fitted and an external signal generator can be connected directly to the EXT I/P connector.
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Frequency and level coupling

Many measurements are made where it is convenient if the carrier frequencies and RF levels of signal sources are automatically related to each other. The coupling setup facility allows two or more signal sources to be coupled together in frequency and/or level. The frequencies can be coupled with a defined offset value (for example, 10.7 MHz), and can be harmonically related. The harmonic relationship is useful where a harmonic sampling gate or divider is being tested. RF levels can be entered in dB. Coupling factors of the B and C sources are always set relative to the A source.
The frequency coupling is entered in the form:

Coupling

where N is an integer between 1 and 9 The B and C sources can be coupled only by entering their value relative to the A source. This
means that if the offset frequency of B relative to A is set as +1 MHz, and C relative to A as +5 MHz, then C is always offset 4 MHz from B. For this reason, if a measurement requires two sources to be coupled they should be set as either A and B with C the independent source, or A and C with B the independent source. Offsets can have either positive or negative values.
Whenever a coupling factor has been set, the signal generator display clearly identifies the presence of coupling factors in the frequency or level display fields by displaying an icon of the form coupled.
Coupling selection
To set the coupling factors proceed as follows: (1) On the Setup Menu press the [Coupling Setup] key to display the Frequency and Level
Frequency (B) = frequency (A)
Frequency (B) = frequency (A)/N
Ö
BC under the frequency/level units to indicate to which sources that parameter is currently
Coupling menu (see Fig. 4-4 below). The screen is split horizontally into two, with the upper part displaying the frequency coupling parameters and the lower part displaying the level coupling parameters.
× N + offset frequency
OR
+ offset frequency
B3414
Fig. 4-4 Frequency and level coupling menu
46882/439 4-5
SETUP
Frequency
(2) Select the required source by toggling between the [A & B Coupling] and [A & C Coupling]
(3) Select [Freq Offset] and enter the requ ired offset from the A source, positive or negative, up
(4) To set the B or C source to a frequency which is a harmonic or sub-harmonic of the A source
(5) If required, select a second source by repeating the above procedure. (6) Press [Enable/Disable] which toggles between the two states shown on the display. When
Level
(2) Select the required source by toggling between the [A & B Coupling] and [A & C Coupling]
(3) Select [Level Offset] and enter the required offset from the A source, p ositive or negative,
(4) If required, select a second source by repeating steps (2) and (3) above. (5) Press [Enable/Disable] which toggles between the two states shown on the display. When
keys.
to the instrument’s maximum frequency and terminate with the [Hz], [kHz], [MHz] or [GHz] key.
press the [Harmonic/Sub-harm] key. This key toggles the soft key selection between [Freq Harmonic] and [Freq Sub-harm]. Enter the required harmonic or sub-harmonic in the range 1 to 9 and terminate with any [ENTER] key.
Enable is selected, the Sig Gen menu is modified by the addition of an arrow and the letter
Ö
for each coupled source in the frequency field. Thus case, the A source is coupled to the B source, the C source or both B and C sources.
keys.
and terminate with the [dB] key.
Enable is selected, the Sig Gen Menu is modified by the addition of an arrow and the letter for each coupled source in the RF level field
B, ÖC or ÖBC indicates that, in this
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Applications summary

The 2026 Multisource Generator supports a number of measurement applications which require more than one signal source to be coupled together. In addition to automatically selecting the most appropriate signal routing format, the applications mode also automatically couples the sources together and modifies the descriptions of the parameters entered to best suit the application. This considerably simplifies control of the sources and provides a clearer description of the measurement being performed.
Whenever an application is selected, the signal routing can be displayed in graphical form to ensure that the user understands how the sources are connected to the RF connectors. In addition, a stylized spectral diagram can be displayed which shows how the main control parameters are used in the test.
Some applications, such as 3-tone intermodulation measurements, cannot be performed using the internal sources of a generator fitted with only two sources. In these circumstances this is clearly indicated on the selection menu.

Applications

Applications selection

To select one of the predefined applications press the [Appl’n Menu] key on the Setup Menu. This causes the Applications Selection Menu (similar to that shown in Fig. 4-5) below to be displayed.
Fig. 4-5 Applications selection menu (shown for three sources fitted)
This menu enables you to perform two- and three-tone intermodulation distortion tests on an amplifier, make a two-tone intermodulation measurement on a receiver or carry out a receiver selectivity test. Intermodulation tests require the presence of one or two strong interfering signals whose intermodulation products fall in the receiver’s or amplifier’s input frequency band.
Note that when two sources are fitted the [Receiver 2tone IM] key does not appear so this test cannot be selected.
B3415
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SETUP

Amplifier intermodulation distortion application

Intermodulation tests on amplifiers are a good indication of the linearity of an amplifier. Many communication systems require devices able to carry two or more signals without introducing spurious frequencies which might affect system performance. The 2026 can support 2-tone and (if three sources are fitted) 3-tone intermodulation testing. The number of tones can also be increased by using the external source input, EXT I/P, for the connection of external generators.
Two-tone test
In this test two tones are input to an amplifier. Amplifier output will comprise not only the two applied tones but also, due to amplifier non-linearity, intermodulation products. One tone is provided from source A at the required amplifier frequency. The second interfering tone is provided from source B at a different frequency but same amplitude.
Three-tone test
In this test three tones are input to an amplifier. As described for the two-tone test above, the amplifier’s non-linearity gives rise to distortion products. When these signals interfere with each other they will either add together to produce a larger amplitude signal or cancel each other depending on the phase of each signal.
The three tones used are: one at the centre frequency (from source A), and two additional, interfering signals (from sources B and C). To find the worst possible case for the amplifier, the phase of one of the signals must be adjusted until the distortion products rise to a maximum level. In the 2026 the peak levels can be identified by phase (or frequency) modulating source C and using a peak hold on the measuring instrument. Alternatively, the phase of source C can be adjusted (with no modulation applied) until a peak response is found.
When phase or frequency modulation is used to peak the measurement rate a default modulation rate of 10 Hz and deviation of 3.2 radians is provided. This can be adjusted by the user to suit the measuring instrument being used.
Procedure
You can carry out an intermodulation distortion test on an amplifier as follows: (1) Press [Amplifier IM] which displays the Intermod. Distortion Test on Amplifier block
diagram as shown in Fig. 4-6 below.
B3416
Fig. 4-6 Intermod. distortion test on amplifier block diagram
(2) Connect the amplifier under test to the COMBINED RF OUTPUT socket as shown by the
block diagram. Since for a 2-tone test the C source is not used, its connection to the combiner is shown dotted.
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APPLICATIONS
(3) Press [Spectral Diagram] which displays the Intermod. Distortion Test on Amplifier spectral
diagram as shown in Fig. 4-7 below.
B3391
Fig. 4-7 Intermod. distortion test on amplifier spectral diagram
(4) The spectral diagram shows the default setting with the B source offset higher in frequency
than the A source (for a 2-tone test) and the C source offset lower in frequency than the A source (for a 3-tone test). You can reverse this setting so that the C source is at the higher frequency by entering a negative offset frequency. Also indicated on the diagram is the ability for you to additionally modulate and adjust the phase of the carrier of the C source for a 3-tone test. Also shown is that all signals have the same RF level.
(5) If you wish to continue, press [Accept Appl’n] otherwise press [EXIT] which returns you to
the Applications Selection Menu to enable you to select an alternative test.
(6) Pressing [Accept Appl’n] displays the screen shown in Fig . 4-8 below. The screen is split
horizontally into two, with the upper part displaying the receiver parameters and the lower part displaying the interferer offset frequency.
B3392
Fig. 4-8 Intermod. distortion test on amplifier: 2-tone selected
(7) Select [Carrier Freq] and [RF Level] to set these parameters. The carrier frequency entered
is that for the A source. The RF level entered is that for all sources, but note that the RF level limit is +4 dBm.
(8) Select [Offset Freq] to change the equidistant offsets of the interferer B and C sources. You
can reverse the relative positions of the B and C sources by entering a negative offset frequency.
(9) Select 2 Tone or 3 Tone by pressing [2 Tone/3 Tone] to toggle between the two selections as
shown on the screen.
46882/439 4-9
SETUP
(10) When you select 3 Tone four additional soft keys are displayed as shown in Fig. 4-9 below.
B3393
Fig. 4-9 Intermod. distortion test on amplifier: 3-tone selected
(11) For 3-tone operation press the [Mod’n Mode] key to access the Modulation Setup Menu
shown in Fig. 4-10 below. This enables you to apply modulation to the C source rather than
ϕ
select the [Auto
M] key. At the conclusion press [EXIT] to return to the previous screen.
(12) Having selected the modulation in step (11) above, press [Mod ON/OFF] to toggle between
the two states as shown by the screen.
B3394
Fig. 4-10 Intermod. distortion test on amplifier: modulation setup menu, ϕM selected
ϕ
(13) For 3-tone operation pressing the [Auto
M] key enables you to automatically set the phase
modulation of the C source. ϕM deviation is set to 3.20 rad at a modulation rate of 10 Hz sine wave. The low modulation rate ensures capture of the worst-case intermodulation products by the spectrum analyzer peak detector.
(14) For 3-tone operation, by pressing [Phase Adjust] and using the control knob you can adjust
the phase offset of the C source carrier with respect to its current phase for maximum distortion products. Turn clockwise to advance the phase and anticlockwise to retard the phase.
(15) At any time during the test you can press [Summary] then [Source Summary] to display the
Source Summary screen similar to that shown in Fig. 4-11 below. This shows the allocated frequencies and levels of all three sources to confirm your selection.
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