Bird Technologies AT-500 User Manual

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INSTRUCTION BOOK

Operator Manual

AT-500 Antenna Tester

Instruction Book Part Number 920-AT500 Rev. C

Safety Precautions

The following are general safety precautions that are not necessarily related to any specific part or procedure, and do not necessarily appear elsewhere in this publica tion. These precautions must be thoroughly understood and apply to all phases of operation and maintenance.

WARNING

Keep Away From Live Circuits

Operating Personnel must at all times observe

general safety precautions. Do not replace

components or make adjustments to the inside of the

test equipment with the high voltage supply turned

on. To avoid casualties, always remove power.

WARNING

Shock Hazard

Do not attempt to remove the RF transmission line

while RF power is present.

WARNING

Do Not Service Or Adjust Alone

Under no circumstances should any person reach

into an enclosure for the purpose of service or

adjustment of equipment except in the presence of

someone who is capable of rendering aid.

Bird AT-500 Antenna Tester

WARNING

Safety Earth Ground

An uniterruptible earth safety ground must be supplied

from the main power source to test instruments.

Grounding one conductor of a two conductor power cable

is not sufficient protection. Serious injury or death can

occur if this grounding is not properly supplied.

WARNING

Resuscitation

Personnel working with or near high voltages

should be familiar with modern methods of

resuscitation.

Safety Symbols

WARNING

Warning notes call attention to a procedure, which if

not correctly performed, could result in personal

injury.

CAUTION

Caution notes call attention to a procedure, which if

not correctly performed, could result in damage to

the instrument.

The caution symbol appears on the equipment indicating there is important information in the instruction manual regarding tha

t particular area

 Note: Calls attention to supplemental

information.

iii

Warning Statements

The following safety warnings appear in the text where there is danger to operating and maintenance personnel, and are repeated here for emphasis.

WARNING

Live RF energy. Do not touch or ground

the center conductor of a live RF

connection. Failure to comply may result

in equipment damage and serious burns

or death to personnel.

On page 17.

WARNING

Care should be taken when handling batteries.

Do not heat or dispose of batteries in fire. May burst

or release toxic materials.

Avoid forced discharge.

Do not short circuit.

Restrict charging current and time to the

recommended value.

Do not solder the battery directly.

Do not disassemble, apply excessive pressure or

deform.

Avoid placing the battery in reverse polarity.

Battery disposal method should be in accordance

with local and state regulations.

On page 39.

WARNING

Replace with ONLY Nickel-Metal hydride (NiMH)

rechargeable AA batteries with a nominal voltage of

1.2V and minimum capacity of 2000mAh. DO NOT

install any type of battery such as alkaline or other

type of secondary (rechargable) batteries.

On page 45.

Bird AT-500 Antenna Tester

WARNING

Charging batteries installed in reverse polarity can

cause the battery to swell or rupture.

On page 45.

Caution Statements

The following equipment cautions appear in the text and are repeated here for emphasis.

CAUTION

Only use the AC adapter provided with the AT. Do

not use the adapter with the batteries removed.

On page 15.

CAUTION

Follow guidelines for battery charging.

Avoid constant charging of batteries for long periods

of time. Overcharging can result in reduced battery

efficiency, service life, and possible permanent

damage.

On pages 15 and 40.

CAUTION

Required input is 11 to 16 VDC @ 250mA. Connector

is wired outside positive, inside negative.

On page 16.

CAUTION

AVOID STATIC DISCHARGE

Use proper Electrostatic Discharge (ESD) precautions to avoid static discharge when making connections to the test port. Equipment failure can

occur if the test port is subjected to ESD.

On page 17.

CAUTION

250mW max. input

Exceeding the maximum input will cause damage to

internal components. Do not connect transmitter

output to the AT-500. Damage can also be caused by

testing antennas near other transmitting antennas. If

testing base station antennas, first measure the power

at the coax end to be sure it does not exceed 250mW.

On page 17.

CAUTION

Harsh or abrasive detergents and some solvents can

damage the display unit and information on labels.

On page 39.

CAUTION

Replace with only the same type and rating fuse.

315mA 250V

On page 46.

Bird AT-500 Antenna Tester

Safety Statements

USAGE

ANY USE OF THIS INSTRUMENT IN A MANNER NOT SPECIFIED BY THE MANUFACTURER MAY IMPAIR THE INSTRUMENT’S SAFETY PROTECTION.

USO

EL USO DE ESTE INSTRUMENTO DE MANERA NO ESPECIFICADA POR EL FABRICANTE, PUEDE ANULAR LA PROTECCIÓN DE SEGURIDAD DEL INSTRUMENTO.

BENUTZUNG

WIRD DAS GERÄT AUF ANDERE WEISE VERWENDET ALS VOM HERSTELLER BESCHRIEBEN, KANN DIE GERÄTESICHERHEIT BEEINTRÄCHTIGT WERDEN.

UTILISATION

TOUTE UTILISATION DE CET INSTRUMENT QUI N’EST PAS EXPLICITEMENT PRÉVUE PAR LE FABRICANT PEUT ENDOMMAGER LE DISPOSITIF DE PROTECTION DE L’INSTRUMENT.

IMPIEGO

QUALORA QUESTO STRUMENTO VENISSE UTILIZZATO IN MODO DIVERSO DA COME SPECIFICATO DAL PRODUTTORE LA PROZIONE DI SICUREZZA POTREBBE VENIRNE COMPROMESSA.

vii

SERVICE

SERVICING INSTRUCTIONS ARE FOR USE BY SERVICE - TRAINED PERSONNEL ONLY. TO AVOID DANGEROUS ELECTRIC SHOCK, DO NOT PERFORM ANY SERVICING UNLESS QUALIFIED TO DO SO.

SERVICIO

LAS INSTRUCCIONES DE SERVICIO SON PARA USO EXCLUSIVO DEL PERSONAL DE SERVICIO CAPACITADO. PARA EVITAR EL PELIGRO DE DESCARGAS ELÉCTRICAS, NO REALICE NINGÚN SERVICIO A MENOS QUE ESTÉ CAPACITADO PARA HACERIO.

WARTUNG

ANWEISUNGEN FÜR DIE WARTUNG DES GERÄTES GELTEN NUR FÜR GESCHULTES FACHPERSONAL.

ZUR VERMEIDUNG GEFÄHRLICHE, ELEKTRISCHE SCHOCKS, SIND WARTUNGSARBEITEN AUSSCHLIEßLICH VON QUALIFIZIERTEM SERVICEPERSONAL DURCHZUFÜHREN.

ENTRENTIEN

L’EMPLOI DES INSTRUCTIONS D’ENTRETIEN DOIT ÊTRE RÉSERVÉ AU PERSONNEL FORMÉ AUX OPÉRATIONS D’ENTRETIEN. POUR PRÉVENIR UN CHOC ÉLECTRIQUE DANGEREUX, NE PAS EFFECTUER D’ENTRETIEN SI L’ON N’A PAS ÉTÉ QUALIFIÉ POUR CE FAIRE.

ASSISTENZA TECNICA

LE ISTRUZIONI RELATIVE ALL’ASSISTENZA SONO PREVISTE ESCLUSIVAMENTE PER IL PERSONALE OPPORTUNAMENTE ADDESTRATO. PER EVITARE PERICOLOSE SCOSSE ELETTRICHE NON EFFETTUARRE ALCUNA RIPARAZIONE A MENO CHE QUALIFICATI A FARLA.

viii

Bird AT-500 Antenna Tester

UNITS ARE EQUIPPED WITH RECHAREABLE BATTERIES.

THESE ARE TO BE REPLACED BY AUTHORIZED SERVICE PERSONNEL ONLY!!!

LAS UNIDADES VIENEN EQUIPADAS CON BATERIAS RECARGABLES.

¡¡¡Y SOLAMENTE EL PERSONAL DE SERVICIO AUTORIZADO PUEDE REEMPLAZARLAS!!!

GERÄTE SIND MIT WIEDER AUFLADBAREN BATTERIEN BESTÜCKT.

BATTERIEN SIND NUR VON QUALIFIZIERTEM SERICE PERSONAL AUSZUWECHSELN!!!

CES DISPOSITIFS SONT ÉQUIPÉS DE BATTERIES RECHARGEABLES.

SEUL LE PERSONNEL D’ENTRETIEN AUTORISÉ EST HABILITÉ À LES REMPLACER !

LE UNITÀ SONO DOTATE DI BATTERIE RICARICABILI,

CHE DEVONO DA COME SPECIFICATO DAL PRODUTTORE LA PROTEZIONE DI SICUREZZA POTREBBE VENIRNE COMPROMESSA.

RF VOLTAGE MAY BE PRESENT IN RF ELEMENT SOCKET - KEEP ELEMENT IN SOCKET DURING OPERATION.

DE LA TENSION H.F. PEAT ÊTRE PRÉSENTE DANS LA PRISE DE L'ÉLÉMENT H.F. - CONSERVER L'ÉLÉMENT DANS LA PRISE LORS DE L'EMPLOI.

HF-SPANNUNG KANN IN DER HF-ELEMENTBUCHSE ANSTEHEN - ELEMENT WÄHREND DES BETRIEBS EINGESTÖPSELT LASSEN.

PUEDE HABER VOLTAJE RF EN EL ENCHUFE DEL ELEMENTO RF - MANTENGA EL ELEMENTO EN EL ENCHUFE DURANTE LA OPERACION.

IL PORTAELEMENTO RF PUÒ PRESENTARE VOLTAGGIO RF - TENERE L'ELEMENTO NELLA PRESA DURANTE IL FUNZIONAMENTO.

Bird AT-500 Antenna Tester

About This Manual

This manual covers the operating and maintenance instructions for the following models:

AT-500

Changes to this Manual

We have made every effort to ensure this manual is accurate. If you discover any errors, or if you have sug gestions for improving this manual, please send your comments to our Solon, Ohio factory. This manual may be periodically updated. When inquiring about updates to this manual refer to the part number and revision on the title page.

Literature Contents

Chapter Layout

Introduction -

ter, lists equipment supplied and optional equipment. Basic Operations -Describes the base level operation

instructions. Installation - Describes the power supply and antenna

connection instructions. Measure Match - -Describes how to use the antenna

tester in it’s various modes of operation. Field Strength - Describes how to use the field strength

detection mode. Maintenance - Describes cleaning, calibration, and other

maintenance procedures vital to the operation of the antenna tester.

Describes the features of the antenna tes-

xii

Safety Precautions . . . . . . . . . . . . . . . . . . . . . . . . ii

Safety Symbols. . . . . . . . . . . . . . . . . . . . . . . . . . . . iii

Warning Statements . . . . . . . . . . . . . . . . . . . . . . . iv

Caution Statements . . . . . . . . . . . . . . . . . . . . . . . . v

Safety Statements . . . . . . . . . . . . . . . . . . . . . . . . vii

About This Manual . . . . . . . . . . . . . . . . . . . . . . . . xi

Changes to this Manual. . . . . . . . . . . . . . . . . . . . . xi

Literature Contents . . . . . . . . . . . . . . . . . . . . . . . . xi

Chapter Layout . . . . . . . . . . . . . . . . . . . . . . . . xi

Chapter 1 Introduction . . . . . . . . . . . . . . . . . . . . . 1

Items Supplied . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Component Description . . . . . . . . . . . . . . . . . . . . . 2

Display Description . . . . . . . . . . . . . . . . . . . . . . . . 4

Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Swept Frequency Mode . . . . . . . . . . . . . . . . . . . 6

Single Frequency Mode . . . . . . . . . . . . . . . . . . . 6

Auto Scaling . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Relative Field Strength . . . . . . . . . . . . . . . . . . . 6

Limit Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Data Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Serial Communication Link . . . . . . . . . . . . . . . 6

Optional Equipment . . . . . . . . . . . . . . . . . . . . . . . 7

Automobile Cigarette

Lighter Adapter (P/N 5A2238-1) . . . . . . . . . . . . 7

Carrying Case (P/N 5000-030) . . . . . . . . . . . . . 7

Verification Kit (P/N 7000A145) . . . . . . . . . . . . 7

Interface Software (P/N 7000B840) . . . . . . . . . 7

xiii

Chapter 2 Basic Operations . . . . . . . . . . . . . . . . . 9

Getting Started . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

“Lo Batt” . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

“Busy” . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

“Hold” . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

“Pass” or “Fail” . . . . . . . . . . . . . . . . . . . . . . . . . 11

“Noise” . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Out of Range Values . . . . . . . . . . . . . . . . . . . . 12

Setting the Auto Shut-Off Timer . . . . . . . . . . 12

Return to Factory Presets . . . . . . . . . . . . . . . . 12

Set Serial Baud Rate . . . . . . . . . . . . . . . . . . . . 13

Chapter 3 Installation . . . . . . . . . . . . . . . . . . . . . 15

Power Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

AC Mains Adapter . . . . . . . . . . . . . . . . . . . . . . 16

Automobile Cigarette

Lighter Adapter Cable . . . . . . . . . . . . . . . . . . . 16

Connecting the Antenna . . . . . . . . . . . . . . . . . . . 17

Chapter 4 Measure Match . . . . . . . . . . . . . . . . . . 19

Understanding the Operating Modes . . . . . . . . . 19

Swept Frequency vs.

Single Frequency . . . . . . . . . . . . . . . . . . . . . . . 19

Measurement Units . . . . . . . . . . . . . . . . . . . . . 20

Rho . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

VSWR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Match Efficiency (%) . . . . . . . . . . . . . . . . . . . . 21

Return Loss (dB) . . . . . . . . . . . . . . . . . . . . . . . 21

Auto Scale vs.

Manual Scale . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Sweep Type-Single Hold vs.

Continuous . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

xiv

Swept Frequency . . . . . . . . . . . . . . . . . . . . . . . . . 23

Select Frequency Band . . . . . . . . . . . . . . . . . . 23

Start Stop MHz . . . . . . . . . . . . . . . . . . . . . . . . 24

Center MHz . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Select Measurement Units . . . . . . . . . . . . . . . 25

Select Auto or Manual Scale . . . . . . . . . . . . . . 25

Auto Scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Manual Scale . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Selecting the Sweep Type . . . . . . . . . . . . . . . . 26

Saving a Trace . . . . . . . . . . . . . . . . . . . . . . . . . 27

Recalling a Trace . . . . . . . . . . . . . . . . . . . . . . . 29

Clearing a Trace . . . . . . . . . . . . . . . . . . . . . . . 29

Limit Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Turn Audio On/Off . . . . . . . . . . . . . . . . . . . . . . 30

Selecting Limit Values . . . . . . . . . . . . . . . . . . 31

VSWR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

% Match . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Return Loss . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

RHO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Using a Trace as the Limit . . . . . . . . . . . . . . . 32

Clearing a Limit . . . . . . . . . . . . . . . . . . . . . . . . 33

Single Frequency . . . . . . . . . . . . . . . . . . . . . . . . . 33

Selecting the Frequency . . . . . . . . . . . . . . . . . 33

Select Measurement Units . . . . . . . . . . . . . . . 34

Select Auto or Manual Scale . . . . . . . . . . . . . . 34

Auto Scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Manual Scale . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Turn Audio On/Off . . . . . . . . . . . . . . . . . . . . . . 35

Chapter 5 Field Strength . . . . . . . . . . . . . . . . . . .37

Field Strength Measurement . . . . . . . . . . . . . . . 37

Turn Audio On/Off . . . . . . . . . . . . . . . . . . . . . . 37

Enter Gain Factor / Select Auto Gain . . . . . . . 37

Auto Gain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Gain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Chapter 6 Maintenance . . . . . . . . . . . . . . . . . . . . 39

Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Charging Batteries . . . . . . . . . . . . . . . . . . . . . . . 39

Batteries and Long Term Storage. . . . . . . . . . . . 40

Operational Tests. . . . . . . . . . . . . . . . . . . . . . . . . 41

Power-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Firmware Rev . . . . . . . . . . . . . . . . . . . . . . . . . 41

Battery Test . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

Display Test . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

Self Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

Battery Replacement . . . . . . . . . . . . . . . . . . . . . . 44

Fuse Replacement . . . . . . . . . . . . . . . . . . . . . . . . 46

Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . 47

The Antenna Tester

will not power up. . . . . . . . . . . . . . . . . . . . . . . 47

NVRAM Test Fails . . . . . . . . . . . . . . . . . . . . . 47

ROM, EEPROM, RAM,

A/D, TEMPR, PLL Test Fails . . . . . . . . . . . . . 48

Stuck Keys Test Fails . . . . . . . . . . . . . . . . . . . 48

“Noise” is Displayed

During Testing . . . . . . . . . . . . . . . . . . . . . . . . . 48

Antenna Tester indicates

a Perfect Match . . . . . . . . . . . . . . . . . . . . . . . . 48

Customer Service. . . . . . . . . . . . . . . . . . . . . . . . . 50

Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

Menu Structure . . . . . . . . . . . . . . . . . . . . . . . . . . 54

Limited Warranty . . . . . . . . . . . . . . . . . . . . . . . . . 55

xvi

xvii

Chapter 1 Introduction

Items Supplied

Figure 1 Supplied Items

1. Bird AT-500

2. AC Mains Adapter

3. Female “N”-Type Connector

4. Field Strength Antenna

5. Instruction Book (Not Shown)

Bird AT-500 Antenna Tester

131

Component Description

Figure 2 Component Description

1. LCD Display Backlit liquid crystal display.

2. External DC Connector

Connect either the ac adapter or the cigarette lighter adapter. External supplies operate the unit and charge the internal battery.

11 10 9 8

Introduction

3. Cursor Keys

Left Arrow Press in swept frequency mode to

move the cursor to the left. Press during data entry to erase data.

Right Arrow Press in swept frequency mode to

move the cursor to the right.

Up Arrow Moves the cursor to the maximum point

on the displayed trace. Press during data entry to increase numeric data.

Down Arrow Moves the cursor to the minimum point

on the displayed trace. Press during data entry to decrease numeric data.

4. Backlight Key Turns the backlight on or off. Backlight is on a timer to increase battery life.

5. On Key Press to turn tester on, press and hold to turn tester off.

6. +/- Key Toggles between positive and negative numbers.

7. Enter Key Completes data entry.

8. ESC Key Back up through menu structure. At the

top menu level, blanks menu. Exits data entry without saving changes.

9. Menu Key Displays software menu and enables menu select keys.

10. Select Key Allows current parameter, indicated by flashing cursor, to be changed. Press again to enable the next parameter to be changed.

11. Numeric Keys Input numeric values.

12. Menu Select

Keys

Used to access the menu sections described directly above them. Can also be used to scroll through available settings in a particular parameter.

13. T est Port Connect antenna or antenna lead.

14. Serial Port Connect communication cable to allow

data transfer to a PC.

Bird AT-500 Antenna Tester

Display Description

Figure 3 Display Description

1.35

Meas Units

69.00 MHz

Sweep Type

2.0

1 2

VSWR

1.0

2.00 MHz 136.00

Band

1.35

69.00 Mhz

1.2

1.5

8910

Busy

8910

7 6 5

LimitTrace

VSWR

Low Batt

7 11

Freq MHz

Units Manual

Scale

Auto Scale

Audio Off

Introduction

1. Sweep Rate

Blinks when sweeping.

Indicator

2. Measurement Units Indicates selected measurement

units.

3. Trace Graphic display of measured results across selected frequency band.

4. Menu Select Key

Labels

5. Frequency Band

Defines function of menu select keys located below the display.

Displays frequency band selected.

Scale

6. Cursor Used to select measurement

position on the trace.

7. Utility Label Area for displaying general data (Lo Batt, Busy, Hold, Noise, and test results).

8. Frequency Selected Frequency (for swept mode this is frequency at the cursor position).

9. Measured Value Numeric display of measured value (for swept mode this is the value at the cursor position).

10. Scale Displays user defined measurement scale.

11. Pointer Moves across scale to show analog type indication of measured value.

Bird AT-500 Antenna Tester

Features

Swept Frequency Mode

Fast scan shows VSWR, ρ, match efficiency or return loss across an entire band. A movable cursor can be used to pinpoint a scan frequency and the correspond ing measurement value is displayed.

Single Frequency Mode

Provides measurement information in units of Reflection Coefficient (ρ); Voltage Standing Wave Ratio (VSWR);% Match, or Return Loss (dB) at one fre quency on a simulated meter movement. An audio generator can be enabled to produce a tone that is pro portional to the match condition.

Auto Scaling

Used in either swept or single frequency modes, sets the Y axis for best measurement display.

Relative Field Strength

Provides means for optimizing the radiated signal of any transmitter within the specified frequency band.

Limit Testing

Quick pass-fail indication; compares measurements to user selected limits.

Data Storage

Saves and recalls up to 12 traces to be used to set limit or long term monitoring of antenna performance.

Serial Communication Link

Built in serial port and optional software uploads data to a personal computer for analysis or storage.

Introduction

Optional Equipment

Automobile Cigarette Lighter Adapter (P/N 5A2238-1)

Connects tester to standard 12V automotive cigarette lighter jack.

Carrying Case (P/N 5000-030)

Convenient and protective, large enough to carry the tester, AC adapter, connectors, field strength antenna and instruction book.

Verification Kit (P/N 7000A545)

Used to verify tester performance. Includes standard mismatch and connector adapter.

Interface Software (P/N 7000B840)

PC software used to upload trace data for analysis, printing or storage.

 Note: System requirements: IBM PC or

equivalent; Windows 95 or later, 6 MB free hard disk space; VGA monitor, open com port. Includes interface cable.

Bird AT-500 Antenna Tester

Chapter 2 Basic Operations

Getting Started

This section describes initial quick steps to get started. For detailed information regarding connecting the Antenna Tester refer to that section at the end of this chapter.

 Note: This unit is shipped with the batter-

ies not charged. Charge batteries overnight or for at least 8 hours before use.

Power On/Off

z To turn the Antenna Tester on, momentarily

press the ON key.

 Note: The results of a self test will be dis-

played if a failure is present. For more information about the self test or a failure, refer to "Maintenance" on page 39.

z To turn the Antenna Tester off, press and hold

the ON key for 1 second.

Backlight

z To turn the backlight on, press the BACK-

LIGHT key.

z To increase or decrease display contrast, press

and hold the BACKLIGHT key while pressing either the UP or DOWN arrow key.

z To turn the backlight off, press the BACK-

LIGHT key.

Bird AT-500 Antenna Tester

Software Menu

z Press the MENU key to display the software

menu.

Blinking Cursor (black square)

The cursor will be blinking in the selected area, indicating that the parameter for that area can be changed.

Enter Key

ENTER

All data entry, and mode changes accessed using select key, require the enter key to be pressed before they are initiated.

Up/Down Arrow Keys

When a function is enabled for change, the UP or DOWN arrow keys can be used to either scroll through

your choices or increase/decrease the numerical value. The actual increments depend on the function.

Left Arrow Key

The LEFT arrow key can be used to backspace erasing one character at a time during data entry.

Escape (ESC)

ESC

Returns to previous menu without initiating a change.

Basic Operations

Select Key

The operator instructions written for this manual were based on stepping through the software menu using the keys below the display. Once you are com

fortable operating the AT-500, you might find it faster to use the SELECT key to access some functions. These include: Units, Scale, Start and Stop Frequencies in swept frequency mode and Units, Scale and Frequency in single frequency mode.

Press the SELECT key until the cursor is blinking at the desired function. The first function enabled depends on the last function selected through the menu.

Messages

There are five utility messages that can be displayed to inform you of equipment, or procedural, conditions.

“Lo Batt”

Displayed when battery voltage is less than 6.6V, see “Charging Batteries” on page 39.

“Busy”

Displayed during mode changes indicating the measurement information is being updated.

“Hold”

Displayed when in the Swept Frequency mode, and Single Hold is the selected sweep type.

“Pass” or “Fail”

Displayed indicating the appropriate results of a limit test.

Bird AT-500 Antenna Tester

“Noise”

Displayed if there is excessive background noise measured. The measurement may not be accurate. See “Troubleshooting” on page 47 if this condition is persistent.

Out of Range Values

When entering numeric data, it is possible to enter a value out of range. Depending on the function, the Antenna Tester will either enter the minimum or max imum value, or the cursor will continue to blink on the function out of range waiting for the correct entry.

Setting the Auto Shut-Off Timer

In order to preserve battery life, the Antenna Tester will automatically shut off after 5,15,30 or 60 minutes without any keystrokes.

Follow the steps below to select the length of time, before auto shut-off occurs.

1. Press the MENU key.

2. Press the UTIL key.

3. Press the TIMER key until the desired interval is displayed.

Return to Factory Presets

When the Antenna Tester is turned on, the various software parameters will be set to the condition they were at when the tester was turned off.

To return the parameters to the factory setting follow the steps below.

z The parameters will be set to the conditions

listed below.

Basic Operations

Software Parameter Factory Setting

Mode Swept Frequency Start 2.0MHz Stop 136.0MHz Measurement Units VSWR Scale min. 1.0; max. 5.0 Sweep Type Continuous Limit Value 1.5 Limit Audio ON Baud Rate 9600 Auto Shut-off Timer 5 Audio ON Cursor 67MHz

1. Press the MENU key.

2. Press the UTIL key.

3. Press the PRESET key.

Set Serial Baud Rate

Measurement data can be transferred between the AT-500 and a personal computer using the serial port and optional interface software. The data can then be used for analysis, printed, or stored.

The data transfer rate (baud rate) between the Antenna Tester and computer must be identical and set to 9600. To change the baud rate for the serial port on the Antenna Tester, follow the steps below.

Complete interface software instructions are included with the software.

1. Press the MENU key.

2. Press the UTIL key.

3. Press the SERIAL key.

4. Repeatedly press the SERIAL key until the 9600 is displayed.

Bird AT-500 Antenna Tester

Chapter 3 Installation

The following paragraphs will explain how to connect the Bird Antenna Tester for various operations. Refer to the component description diagram on

Power Supply

The AT-500 can use an external power source. Using the ac adapter or the 12V cigarette lighter adapter will also charge the battery. Using the ac adapter, charge time is about 8 hours. Using the cigarette lighter adapter, charge time will depend on the car battery charge. Battery life is 2 hours continuous operation, minimum, with the backlight on. “Lo Batt” is dis played when the batteries require charging.

 Note: This unit is shipped with the batter-

ies not charged. Charge batteries for at least 8 hours before use.

CAUTION

Follow guidelines for battery charging.

page 2 if needed.

Avoid constant charging of batteries for long periods of

time. Overcharging can result in reduced battery

efficiency, service life, and possible permanent damage.

 Note: For optimum battery life, only

charge the batteries after the low battery indicator is displayed.

CAUTION

Only use the AC adapter provided with the AT. Do

not use the adapter with the batteries removed.

Bird AT-500 Antenna Tester

AC Mains Adapter

To use the AC adapter, insert the adapter’s barrel connector into the Antenna Tester’s DC jack. Insert the adapter plug into a wall receptacle.

CAUTION

Required input is 11 to 16 VDC @ 250mA. Connector

is wired outside positive, inside negative.

Automobile Cigarette Lighter Adapter Cable

 Note: Before inserting the adapter’s barrel

connector into the Antenna Tester’s DC jack (Figure 4), verify that the polarity of the adapter barrel is correct (Figure 4). The negative (–) symbol must be adjacent to the word TIP as the center is negative and the outside is positive.

Insert the adapter plug into a cigarette lighter.

Figure 4 Cigarette Lighter Adapter Cable

Tip Connection

CORRECT

NEGATIVE VOLTAGE AT CENTER CONDUCTOR OF ADAPTER BARREL

WRONG !!

POSITIVE VOLTAGE AT CENTER CONDUCTOR OF ADAPTER BARREL

Connecting the Antenna

WARNING

Live RF energy. Do not touch or ground

the center conductor of a live RF

connection. Failure to comply may result

in equipment damage and serious burns

or death to personnel.

CAUTION

AVOID STATIC DISCHARGE

Use proper Electrostatic Discharge (ESD)

precautions to avoid static discharge when making connections to the test

port. Equipment failure can occur if the

test port is subjected to ESD.

CAUTION

250mW max. input

Exceeding the maximum input will

damage the unit. Do not connect

transmitter output to the AT-500. Damage

can also be caused by testing antennas

near other transmitting antennas. If

testing base station antennas, first

measure the power at the coax end to be

sure it does not exceed 250mW.

Installation

Antenna leads and the Field Strength Antenna are connected to the test port. A known good RF cable can be used to connect the antenna tester directly to a cou pler box, bypassing the antenna system lead. A female TNC connector is provided. Other connectors are avail able, see Parts List in the maintenance section for more information.

Bird AT-500 Antenna Tester

Special consideration must be given to the RF energy present at the feed line of site antennas. At active sites, RF energy from transmitters can be coupled to the antenna under test. If large enough, these signals will cause inaccurate measurements. For best results, the AT-500 should be used with all transmit antennas powered down.

Chapter 4 Measure Match

Understanding the Operating Modes

The Antenna Tester is connected and the operating frequency band is selected. User selections are custom ized, the power is on, and the top level menu is displayed (see “Basic Operations” on page 9).

Since the AT-500 will change the way antennas are tested, Bird recommends taking some time to explore the different operating modes and find what is best for specific applications.

Swept Frequency vs. Single Frequency

Swept frequency graphically displays the unit of measure over a band of frequencies. The cursor, a vertical dotted line, can be moved with the arrow keys to pin point a particular frequency. The measured match value and the frequency at the cursor position are shown at the top of the display.

Figure 5 Swept Frequency

1.3

69.00 MHz

VSWR

1.5

1.2

Swept Freq

2.00

Single Freq

MHz 136.00

Field

Util Test

Str

Single Frequency mode displays the unit of measure in a simulated analog meter graphic. This mode, particularly when audio is on, is useful when tuning an antenna.

Bird AT-500 Antenna Tester

Figure 6 Single Frequency

1.3

69.00 MHz

VSWR

Units Manual

Scale

1.5

Auto Scale

Audio Off

Freq MHz

1.2

Measurement Units

Rho (Reflection Coefficient), VSWR (Voltage Standing Wave Ratio), Match Efficiency (%), and Return Loss (dB), are different units of measurement that can be used to present the same information. (Similarly, Cel sius and Fahrenheit are different units of measurement used to express the same temperature). These units can be used to express the degree of match between an antenna system and a transceiver.

Rho

Rho is the ratio of reflected wave voltage to forward wave voltage. A perfect antenna would not have any reflected waves, hence would have a 0.00 reflection coefficient.

VSWR

VSWR refers to the ratio of maximum and minimum voltages that are set up on a transmission line result ing from the combination of a forward wave and reflected wave. If the antenna system is perfectly matched, the VSWR would be 1:1 and shown as 1.00.

Measure Match

Match Efficiency (%)

Match Efficiency (%) indicates how much of the transmitted power is being used and how much is wasted. If the antenna system is perfectly matched, the Match Efficiency would be 100%.

Return Loss (dB)

Return Loss (dB) is a comparison of the reflected signal to the forward signal in decibels. If the antenna system is perfectly matched, the Return Loss would be negative infinity dB.

Antenna manufacturers often use VSWR for specifications. Match Efficiency is popular for testing because it is easy to determine a good match versus a bad match. For example a system with a VSWR of 1.50 would show

-13.98 dB Return Loss and 96% Match Efficiency.

Auto Scale vs. Manual Scale

In swept mode Auto Scaling sets the measurement unit scale to make the trace easier to read. However, if you plan to look at the size or shape of traces for quick com parisons, it might be more meaningful to set a standard scale. Remember that it is possible to set the scale man ually so the information is not on the display at all.

Figure 7 Auto Scaling Swept Frequency Mode

1.5

VSWR

1.2

Swept Freq

2.00

Single Freq

1.3

69.00 MHz

MHz 136.00

Field Str

Util Test

Bird AT-500 Antenna Tester

Figure 8 Manual Scaling Swept Frequency Mode

1.3

2.00

Single Freq

69.00 MHz

MHz 136.00

Str

Util TestField

VSWR

1.0

Swept Freq

2.0

In the single frequency mode Auto Scaling sets the measurement unit scale so the pointer is mid range of the previous reading. The maximum and minimum scale values are approximately 10% higher or lower than the measured value.

Figure 9 Manual Scaling Swept Frequency Mode

1.3

69.00 MHz

1.2

VSWR

1.5

Freq MHz

Units Manual

Scale

Auto Scale

Audio Off

This setting is an operator preference based on the mode that best presents the desired information.

Measure Match

Figure 10 Manual Scaling Single Frequency Model

1.3

69.00 MHz

VSWR

Units Manual

Scale

5.0

Auto Scale

Audio Off

Freq Mhz

1.0

Sweep Type-Single Hold vs. Continuous

Continuous sweep continually sweeps the selected frequency band updating the measured value with each sweep. An asterisk (*) is blinking on the left side of the display to indicate sweep rate. The single hold mode will freeze a trace on the display and hold is displayed on the right. Holding a trace is also helpful before sav ing the trace, (more about saving traces under that heading later in this section).

Swept Frequency

Select Frequency Band

There are two options for selecting the frequency band. The first is simply to enter the start and stop frequen cies. The second is to enter a span frequency, which is the desired width of the band, and a center frequency, that will be used as the center of the band.

1. Press the MENU key.

2. Press the SWEPT FREQ key.

3. Press the BAND key.

4. Depending on desired method press either Start Stop MHz or Center MHz:

Bird AT-500 Antenna Tester

Start Stop MHz

 Note: The cursor will blink on the start fre-

quency and Start Stop MHz will be highlighted.

1. Enter the frequency using the numeric keypad or

change the frequency using the UP/DOWN arrow keys.

2. Press the ENTER key. The cursor will blink on the

stop frequency.

3. Enter the frequency using the numeric keypad or

change the frequency using the UP/DOWN arrow keys.

4. Press the ENTER key. The tester will begin sweeping.

Center MHz

 Note: The cursor will blink on the Center

frequency and Center MHz will be highlighted.

1. Enter the frequency using the numeric keypad or

change the frequency using the UP/DOWN arrow keys.

2. Press the ENTER key.

 Note: The tester will begin sweeping.

3. Press the SPAN key.

4. Enter the frequency using the numeric keypad or

change the frequency using the UP/DOWN arrow keys.

5. Press the ENTER key.

 Note: The tester will begin sweeping.

Measure Match

Select Measurement Units

Antenna match information can be presented using four different measurement units. Depending on the application, follow the steps below to select Rho, VSWR,%Match or Return Loss.

1. Press the MENU key.

2. Press the SWEPT FREQ key.

3. Press the MEAS UNITS key.

4. Press the UNITS key.

5. Press either the RHO, VSWR,%MATCH or RETURN LOSS key.

 Note: The selected unit will be shown on

the left side of the display.

6. Press RETURN to go back one menu level or MENU to return to the top menu level.

Select Auto or Manual Scale

Selecting the scale simply sets up how the information will look on the display.

1. Press the MENU key.

2. Press the SWEPT FREQ key.

3. Press the MEAS UNITS key.

4. Depending on desired mode press either AUTO or MANUAL SCALE:

Auto Scale

The units scale changes and the Antenna Tester begins sweeping.

Bird AT-500 Antenna Tester

Manual Scale

 Note: The cursor will blink on the mini-

mum scale value and Manual Scale will be highlighted.

1. Enter the desired value using the numeric key-

pad or change the value using the UP/DOWN

arrow keys.

2. Press the ENTER key.

 Note: The cursor will blink on the maxi-

mum scale value.

3. Enter the desired value using the numeric keypad

or change the value using the UP/DOWN arrow keys.

4. Press the ENTER key. The tester will begin sweeping.

 Note: If an out of range value is entered,

the minimum (if under-range) or maximum (if over-range) value will be substituted. If a maximum value that is lower than the minimum value is entered, the cursor will blink again on the minimum value waiting for a correct entry. The actual range depends on the units selected.

 Note: HINT: Using the arrow keys will

keep you in the acceptable range. If you are not sure if the larger value should be at the top or bottom of the scale, press the auto scale key to see where the software puts it.

Selecting the Sweep T ype

Sweep types are continuous or single hold. Continuous will sweep and update the trace automatically. Single hold will sweep once and the trace will remain in the display. Each time single hold is pressed, the trace is updated.

Measure Match

1. Press the MENU key.

2. Press the SWEPT FREQ key.

3. Press the SWEEP TYPE key.

4. Do one of the following, depending on desired mode:

z Press SINGLE HOLD key.

 Note: HOLD will be displayed.

z Press CONT key.

 Note: The tester begins sweeping.

Saving a Trace

The AT-500 can store up to 12 traces. A saved trace can be used to evaluate long term antenna performance, compare performance under different conditions or for comparison to another antenna. A saved trace is also a powerful tool in limit testing (more about limit testing later in this sec tion). The information can later be uploaded to a PC using optional interface software and the serial port. Traces are stored in nonvolatile memory so they are not lost when the Antenna Tester is turned off.

Since the reflection coefficient is the information actually saved when saving a trace, and everything else is calcu lated from that, you have some flexibility when using the trace for comparison. For example, if you save a trace dis played in VSWR, you can compare it to a trace displayed in %Match. You can also change the frequency band of the new trace to effectively zoom in on a particular sec tion of the saved trace. This may be helpful in pinpointing a problem area in a failed limit test.

Bird AT-500 Antenna Tester

Figure 11 Save a Trace

2.0

1.3

69.00 MHz

Reg-5 Empty

<HOLD>

More Save

VSWR

1.0

Reg-1 Empty

2.00

MHz 136.00

Reg-2 Empty

Reg-3 Empty

The desired units, band, and scale should be selected. You should be in the single hold mode and the trace you want stored should be displayed. If continuous sweep type is selected, the trace displayed when you save will be stored.

1. Press the MENU key.

2. Press the SWEPT FREQ key.

3. Press the TRACE key.

4. Press the SAVE TRACE key.

5. Press a REG-n key that has EMPTY displayed.

6. Do one of the following: z If a full register is selected, the new trace will

overwrite the old trace.

z If registers 1-4 are full, press the MORE SAVE

key to access 5-8 and again to access 9-12.

 Note: If needed, use the ESC key to back up.

 Note: HINT: It is a good idea to keep a

record of which traces are in which register as they are identified by register number only.

Measure Match

Recalling a Trace

Follow the steps below to recall a saved trace.

1. Press the MENU key.

2. Press the SWEPT FREQ key.

3. Press the TRACE key.

4. Press the RECALL TRACE key.

5. Press the REG-n key for the desired trace, press the MORE RECALL key to access 5-8 and again to access 9-12. If needed, use the ESC key to back up. The saved trace will be displayed and the corresponding register number will be shown at the bottom of the display.

 Note: The arrow keys can be used to move

the cursor, and the corresponding measurement and frequency at the cursor will be displayed. Remember the up arrow key will move the cursor to the highest value on the trace and the down arrow key will move it to the lowest.

z Press the RETURN key to return to register

selection.

z Press the ESC key to return to trace menu.

Clearing a Trace

When a trace is no longer needed or you need to clear registers for space, follow the steps below.

1. Press the MENU key.

2. Press the SWEPT FREQ key.

3. Press the TRACE key.

Bird AT-500 Antenna Tester

4. Press the CLEAR TRACE key.

5. Press the REG-n key for the desired trace, press the MORE CLEAR key to access 5-8 and again to access 9-12. If needed, use the ESC key to back up. The word full will be replaced by empty at the selected register.

6. Press the ESC key to return to the trace menu.

Limit Testing

Limit testing is a quick pass-fail test using operator defined limits or a stored trace as a minimum for acceptability. Pass or fail will be displayed at the top of the display and an audible tone can be enabled to indi cate a fail situation.

Limit testing is probably the most labor-efficient mode for operating the AT-500. Since all the software set tings are retained when the tester is turned off, once the limit test is set up its simply a matter of connect ing the next antenna system, turning on the power and reading pass or fail.

Turn Audio On/Off

Audio tone for fail indication.

1. Press the MENU key.

2. Press the SWEPT FREQ key.

3. Press the LIMIT key.

4. Pressing the AUDIO key will toggle between on and off.

Measure Match

Selecting Limit Values

Valid limit values depend on measurement units selected. Valid entries are:

VSWR

Between 1.0 and 100.0

% Match

Between 0 and 100%

Return Loss

Between -32 and 0 dB

RHO

Between 0.000 and 1.000

1. Press the MENU key.

2. Press the SWEPT FREQ key.

3. Press the LIMIT key.

4. Press the VALUE key. The cursor will blink next to off.

5. Enter the desired value using the numeric key- pad or change the value using the UP/DOWN arrow keys.

6. Press the ENTER key.

 Note: Pass or Fail will be displayed, a tone

will be heard for fail if audio is enabled.

Bird AT-500 Antenna Tester

Using a Trace as the Limit

The trace you want to use for the limit must be saved. You can have the current antenna test running or start it after you set up the limit test.

Figure 12 Dotted Outline of Limit Trace

1.3

2.0

VSWR

1.0

Swept Freq

69.00 MHz

2.00 MHz 136.00

Single Freq

Field Str

PASS

Util Test

1. Press the MENU key.

2. Press the SWEPT FREQ key.

3. Press the LIMIT key.

4. Press the TRACE - > LIMIT key.

5. Press the REG-n key where the trace is stored.

 Note: A dotted outline of the limit trace will

be displayed with the new trace displayed over it. Pass or Fail will be displayed.

 Note: You can still move the cursor,

change measurement units, frequency band and scale. The dotted outline of the limit trace will be automatically adjusted to provide a direct comparison with the antenna system under test.

Measure Match

Clearing a Limit

Follow the steps below to clear either an operator defined limit value or a trace limit. The trace will still be stored in memory, the limit value will be erased.

1. Press the MENU key.

2. Press the SWEPT FREQ key.

3. Press the LIMIT key.

4. Press the CLEAR LIMIT key.

The value field will change to off if an operator value was being used, the dotted outline of the limit trace will be removed if a trace was being used.

Single Frequency

This mode is useful for tuning antennas, particularly with the audio on. The frequency can be selected fol lowing the instructions below.

Selecting the Frequency

1. Press the MENU key.

2. Press the SINGLE FREQ key.

3. Press the FREQ MHZ key. The cursor will be blinking at the frequency and Freq MHz will be highlighted.

4. Enter the desired frequency using the numeric keypad or change the value using the UP/DOWN arrow keys.

5. Press the ENTER key. The measured value and the frequency will be shown at the top of the display.

Bird AT-500 Antenna Tester