Tektronix 2715 User Manual

Service Manual

2715 Spectrum Analyzer Volume 1

070-9096-06

This document supports firmware version

12.01.95 and above.

Warning

The servicing instructions are for use by qualified personnel only. To avoid personal injury, do not perform any servicing unless you are qualified to do so. Refer to all safety summaries prior to performing service.

www.tektronix.com

Tektronix products are covered by U.S. and foreign patents, issued and pending. Information in this publication supercedes that in all previously published material. Specifications and price change privileges reserved.

Tektronix, Inc., P.O. Box 500, Beaverton, OR 97077

TEKTRONIX and TEK are registered trademarks of Tektronix, Inc.

WARRANTY

Tektronix warrants that this product will be free from defects in materials and workmanship for a period of one (1) year from the date of shipment. If any such product proves defective during this warranty period, Tektronix, at its option, either will repair the defective product without charge for parts and labor, or will provide a repl acement in exchange for the defective product.

In order to obtain service under this warranty, Customer must notify Tektronix of the defect before the expiration of t he warranty period and make suitable arrangements for the performance of service. Customer shall be responsible for packaging and shipping the defective product to the service center de signated by Tektronix, with shipping charges prepaid. Tektronix shall pay for the return of the product to Customer i f the shipment is to a location within the country in which the Tektronix service center is located. Custome r shall be responsible for paying all shipping charges, duties, taxes, and any other charges for products returned to any other locations.

This warranty shall not apply to any defect, failure or damage caused by improper use or improper or inadequate maintenance and care. Tektronix shall not be obligated to furnish service under this warranty a) to repair damage resulting from attempts by personnel other than Tektronix representatives to install, repair or service the product; b) to repair damage resulting from improper use or connection to incompatible equipment; or c) to service a product that has been modified or integrated with other products when the effect of such modification or integration increases the time or difficulty of servicing the product.

THIS W ARRANTY IS GIVEN BY TEKTRONIX WITH RESPECT TO THIS PRODUCT IN LIEU OF ANY OTHER WARRANTIES, EXPRESSED OR IMPLIED. TEKTRONIX AND ITS VENDORS DISCLAIM ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. TEKTRONIX’ RESPONSIBILITY TO REPAIR OR REPLACE DEFECTIVE PRODUCTS IS THE SOLE AND EXCLUSIVE REMEDY PROVIDED TO THE CUSTOMER FOR BREACH OF THIS W ARRANTY. TEKTRONIX AND ITS VENDORS WILL NOT BE LIABLE FOR ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES IRRESPECTIVE OF WHETHER TEKTRONIX OR THE VENDOR HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES.

Specifications

Operating Information

General Safety Summary ix...................................

Service Safety Summary xi....................................

Preface xv...................................................

Electrical Characteristics 1-1..........................................

Instrument Description 2-1............................................

Conformance to Industry Standards 2-2..................................

Product Service 2-2..................................................

Instrument Construction 2-3...........................................

Installation and Preparation for Use 2-3..................................

Power Cord 2-3.....................................................

Replacing the Fuse 2-4...............................................

Selected Components 2-4.............................................

Assembly and Circuit Numbering 2-4...................................

Accessories 2-4.....................................................

Menus 2-4.........................................................

SWP/TRG Menu Structure 2-6.........................................

UTIL Menu Structure

(1 of 2) 2-7.....................................................

UTIL Menu Structure

(2 of 2) 2-8.....................................................

MRK/FREQ Menu Structure 2-8.......................................

CATV/APPL CATV Measurements Page 1 Menu Structure (1 of 3) 2-9........

CATV/APPL CATV Measurements Page 1 Menu Structure (2 of 3) 2-10........

CATV/APPL CATV Measurements Page 1 Menu Structure (3 of 3) 2-11........

CATV/APPL CATV Measurements Page 2 Menu Structure (1 of 2) 2-12........

CATV/APPL CATV Measurements Page 2 Menu Structure (2 of 2) 2-13........

CATV/APPL Applications Menu Structure 2-14............................

DEMOD Menu Structure 2-14..........................................

DSPL Menu Structure 2-15............................................

USER DEF Menu Structure 2-15........................................

INPUT Menu Structure 2-16...........................................

Theory of Operation

Block Diagram Description 3-1........................................

Center Frequency Control 3-5.........................................

1st LO Buffer 3-7...................................................

Sweep 3-7.........................................................

Display System 3-8..................................................

Circuit Description 3-9........................................

Attenuator and 1st Converter 3-9.......................................

RF Mother Board and Phase Locked 2nd LO 3-12..........................

2715 Spectrum Analyzer Service Manual

Table of Contents

1st LO Interface, 1st LO, and 1st LO Buffer Amplifier 3-14..................

Reference Oscillator 3-16..............................................

Phase Lock Assembly (Center Frequency Control System) 3-21...............

Variable Resolution Module 3-33........................................

RF Options 3-35.....................................................

Log Amplifier 3-38...................................................

Display Storage 3-40..................................................

Microprocessor 3-60..................................................

GPIB, RS-232, Real Time Clock, NVRAM, and Gated Measurement Functions 3-74

Video Demodulator 3-78...............................................

Sweep 3-80.........................................................

Front Panel 3-83.....................................................

Power Supply (Primary and Secondary) 3-87..............................

Power Supply (Display) 3-91...........................................

Performance Verification

Incoming Inspection Test 4-1..........................................

Verification of Tolerance Values 4-1....................................

History Information 4-1..............................................

Equipment Required 4-2..............................................

Power-Up Procedure 4-3..............................................

Front Panel Operation 4-4.............................................

Performance Check Procedure 4-4......................................

Adjustment Procedures

Static Discharge Precautions 5-1.......................................

Recommended Test Equipment 5-2.....................................

Preparation 5-4.....................................................

Adjustments Requiring Flatness Correction 5-4...........................

Instrument Bottom View 5-5..........................................

Adjustments 5-6....................................................

Maintenance

Static Sensitive Components 6-1.......................................

Preventive Maintenance 6-2...........................................

Troubleshooting 6-6.................................................

Cal Debug Flags 6-8.................................................

Corrective Maintenance 6-13...........................................

Assembly Replacement Requiring Flatness Correction 6-17...................

Removing and Replacing Assemblies and Subassemblies 6-17................

Maintenance Adjustments 6-33.........................................

Options Replaceable Electrical Parts Diagrams Replaceable Mechanical Parts

2715 Spectrum Analyzer Service Manual

List of Figures

Table of Contents

Figure 1-1: Typical Accuracy Limits for Carrier-to-Noise

Measurement 1-7..........................................

Figure 1-2: Typical Accuracy Limits for CTB Measurement 1-7......

Figure 1-3: Typical Accuracy Limits for Nongated CSO

Measurement 1-8..........................................

Figure 1-4: Typical Accuracy Limits for Gated CSO

Measurement 1-8..........................................

Figure 1-5: Typical ACL Measurement Limits for 2 dB Accuracy 1-9..

Figure 1-6: Typical D/U Measurement Range Limits for

2 dB Accuracy 1-9.........................................

Figure 1-7: Typical Digital Signal CSO Measurement Range Limit

for 2 dB Accuracy 1-10......................................

Figure 1-8: Typical Digital Signal CTB Measurement Range

Limit for 2 dB Accuracy 1-10.................................

Figure 2-1: 2715 Front Panel Keys 2-5............................

Figure 3-1: Main Block Diagram 3-2.............................

Figure 3-2: Display System Diagram 3-8..........................

Figure 3-3: Attenuator and 1st Converter Diagram 3-10..............

Figure 3-4: Equivalent Circuit for the Bandpass (4 Cavity)

Filter 3-11.................................................

Figure 3-5: Block Diagram of RF Mother Board 3-12................

Figure 3-6: 1st LO Interface and 1st LO Diagram 3-14...............

Figure 3-7: 1st LO Buffer Amplifier Diagram 3-15..................

Figure 3-8: Reference Oscillator Diagram 3-17......................

Figure 3-9: Crystal Heater and 15 V Regulation Circuit 3-18..........

Figure 3-10: Oscillator AC Equivalent 3-19........................

Figure 3-11: Oscillator DC Equivalent 3-20........................

Figure 3-12: Phase Lock Center Frequency Control

Configuration for Wide Spans (Unlocked, Sweep Main Coil) 3-28..

Figure 3-13: Phase Lock Center Frequency Control Configuration

for Moderate Spans (Unlocked, Sweep FM Coil) 3-29.............

Figure 3-14: Phase Lock Center Frequency Control Configuration

for Narrow Spans (Locked, Sweep VCO) 3-30...................

Figure 3-15: Variable Resolution Module Diagram 3-34..............

Figure 3-16: RF Options Diagram 3-36............................

2715 Spectrum Analyzer Service Manual

iii

Table of Contents

Figure 3-17: Timing Diagram for a Typical Write to the Control

Figure 3-18: Timing Diagram of a Typical Sweep for the Horizontal

Tracking A/D Converter 3-51.................................

Figure 3-19: Sequence of Events When Writing Data to the

Waveform Memory 3-54.....................................

Figure 3-20: How a Vertical Scan is Performed 3-56.................

Figure 3-21: The Display of a Single Vector of a Waveform 3-57.......

Figure 3-22: A Single Column of Character Dots 3-57................

Figure 3-23: Vertical Output Integrator 3-58.......................

Figure 3-24: Microprocessor Block Diagram 3-61...................

Figure 3-25: Microprocessor Counter System (CPU) 3-62.............

Figure 3-26: Front Panel Block Diagram 3-83......................

Figure 3-27: How the Debounce Circuit Reacts to Key Closure 3-85....

Figure 3-28: Power Supply Primary Block Diagram 3-88.............

Figure 3-29: Display Amplifiers Block Diagram 3-91................

Figure 4-1: 3rd Order IM Test Setup (25 MHz Separation) 4-17.......

Figure 4-2: Harmonic Distortion Test Equipment Setup 4-18..........

Figure 4-3: 1 dB Compression Point Test Setup 4-20.................

Figure 4-4: Accessory Connector (J103) 4-22.......................

Figure 4-5: Test Equipment Setup for Checking Return Loss 4-28.....

Figure 4-6: Test Signal on Video Line 17 4-32.......................

Figure 4-7: Video Gating Check Waveform (NTSC Illustrated) 4-34....

Figure 4-8: IF Gating Check Waveform (NTSC Illustrated) 4-35......

Figure 5-1: Instrument Bottom View 5-5..........................

Figure 5-2: Display Storage Board Adjustment Locations 5-13........

Figure 5-3: Properly Adjusted Checkerboard Pattern 5-14...........

Figure 5-4: Locked 2nd LO and 5 MHz Bandpass Filter

Adjustments 5-16...........................................

Figure 5-5: Phase Lock CFC Module Adjustment and Test Point

Locations 5-17.............................................

Figure 5-6: Log Board Adjustment and Test Point Locations 5-21.....

Figure 5-7: CAL Level Adjustment on Reference Oscillator Board 5-26.

Figure 5-8: RF Option Adjustment Locations 5-28..................

Figure 5-9: Variable Resolution Module Adjustment Locations 5-29....

Figure 5-10: Flatness adjustment test setup (all instruments

except Option 50) 5-34.......................................

2715 Spectrum Analyzer Service Manual

Table of Contents

Figure 5-1 1: Presetting the Flatness Adjustments on the

Log Board 5-35............................................

Figure 5-12: Gain Step Reference Test Setup 5-36...................

Figure 5-13: Internal Ref Ampltd Test Setup 5-38...................

Figure 5-14: SW410 on the Reference Oscillator Board 5-39..........

Figure 5-15: Adjustment and Test Point Locations on the

Sweep Board 5-41..........................................

Figure 5-16: Typical FM Adjustment Waveform 5-42................

Figure 5-17: HPF Tuning Criteria (at TP110M) 5-45.................

Figure 5-18: Typical Video Waveform 5-48.........................

Figure 5-19: Horizontal Sync Output 5-49.........................

Figure 5-20: Vertical Sync Output Waveform 5-50..................

Figure 5-21: E/O Output Waveform 5-51..........................

Figure 5-22: Test Equipment Characterization Using a Dual

Channel Power Meter for split75 5-59..........................

Figure 5-23: Test Equipment Characterization Using a

Single Channel Power Meter to Characterize the Power Meter

Output for split75 5-59......................................

Figure 5-24: Test Equipment Characterization Using a

Single Channel Power Meter to Characterize the DUT

Output for split75 5-59......................................

Figure 5-25: Test Equipment Characterization Using a Dual

Channel Power Meter for split50 5-60..........................

Figure 5-26: Test Equipment Characterization Using a

Single Channel Power Meter to Characterize the Power Meter

Output for split50 5-60......................................

Figure 5-27: Test Equipment Characterization Using a

Single Channel Power Meter to Characterize the DUT

Output for split50 5-60......................................

Figure 5-28: Flatness Test Setup (75 W) 5-62.......................

Figure 5-29: Flatness Test Setup (50 W) 5-62.......................

Figure 6-1: Main Extender and Secondary Extender 6-4............

Figure 6-2: Signal Steering Square Pins 6-5.......................

Figure 6-3: Surface Mounted Components Lead Configuration 6-14...

Figure 6-4: Top View of Assemblies and RF Deck 6-18...............

Figure 6-5: Assemblies Seen from the Bottom of the Spectrum

Analyzer 6-19..............................................

Figure 6-6: Removing the Front Panel 6-22........................

Figure 6-7: Locations of J510 and J550 on the Phase Lock

Assembly 6-23.............................................

2715 Spectrum Analyzer Service Manual

Table of Contents

Figure 6-8: Connector Locations on the RF Deck 6-24...............

Figure 6-9: RF Deck Screws and Nuts 6-25.........................

Figure 6-10: Fan and Fan Mounting Springs Detail 6-29.............

Figure 6-11: Power Supply Assembly Removal (Bottom View) 6-31....

Figure 6-12: Removing Power Supply Attaching Nuts 6-32...........

Figure 6-13: Location of R602 on the Phase Lock CFC Board 6-34.....

Figure 7-1: Option 15 Installation 7-3............................

Figure 10-1: Cabinet 10-7.......................................

Figure 10-2: Front Panel 10-11....................................

Figure 10-3: Power Supply 10-15..................................

Figure 10-4: Chassis #1 10-18.....................................

Figure 10-5: Chassis #2 10-22.....................................

Figure 10-6: Accessories 10-25....................................

2715 Spectrum Analyzer Service Manual

List of Tables

Table of Contents

T able 1-1: CA TV Characteristics 1-2............................

Table 1-2: Frequency-Related Characteristics 1-11..................

Table 1-3: Frequency/Amplitude Related Characteristics 1-13........

T able 1-4: Amplitude-Related Characteristics 1-14..................

Table 1-5: Input/Output Signal Characteristics 1-17................

Table 1-6: Power Requirements 1-19.............................

Table 1-7: Supplementary Characteristics Due to Options 1-19.......

T able 1-8: General Characteristics 1-20...........................

Table 1-9: Environmental Characteristics 1-21.....................

Table 1-10: Physical Characteristics 1-22.........................

Table 1-11: Certifications and Compliances 1-23....................

Table 1-12: Safety Certification Compliance 1-24...................

Table 1-13: Safety Standards 1-24................................

Table 3-1: Input and Output Bit Definition 3-21....................

Table 3-2: Mode Control Register 1 3-41..........................

Table 3-3: Mode Control Register 2 3-42..........................

T able 3-4: Truth Table for the B,C-Save A Display Screen

Offset 3-43...............................................

T able 3-5: Truth Table for the Acquisition Modes 3-43..............

Table 3-6: Mode Control Register 2 3-43..........................

Table 3-7: Enhanced Mode MKRWFM[3..2] Bit Assignment 3-44.....

Table 3-8: Enhanced Mode MKRWFM[1..0] Bit Assignment 3-45....

Table 3-9: Display Control Register 3-45..........................

Table 3-10: Scroll Register 3-46..................................

Table 3-11: Memory Map for the Display Storage Board 3-48.........

Table 3-12: Control Register Latch and Tristate Buffer

Reference Designators and Microprocessor I/O Port

Address Location 3-49......................................

Table 3-13: Input Conditions Required to Write Either the

Max or Min Accumulators to Waveform Memory 3-53...........

Table 3-14: Page Number/Waveform Relation 3-55.................

Table 3-15: Interrupt Controller Input Connections 3-63............

Table 3-16: Configuration of Jumpers/Wires for Various

Memory IC Sizes 3-65......................................

Table 3-17: Definition of Software Jumpers 3-66....................

2715 Spectrum Analyzer Service Manual

vii

Table of Contents

Table 3-18: Power Supply and Serial Bus Connector (J10)

Signal Names and Definitions 3-68............................

Table 3-19: Microprocessor Interface Connector (J550)

Signal Names and Definitions 3-69............................

T able 3-20: Microprocessor Counter Section Connector

Signal Names and Definitions 3-70............................

Table 3-21: Connectors and Signal Names for the Frequency

Counter Section 3-70.......................................

Table 3-22: Pinout for the 24-Pin DIN Connector (J10) Between the

Microprocessor Board, Power Supply Interconnect,

and Serial I/O 3-71.........................................

Table 3-23: Pinout for the Microprocessor Board Test

Connector (J150) 3-71......................................

Table 3-24: Pinout for the 50 Pin Connector (J550) Between

the Microprocessor, Display Storage, and Digital Options

Boards 3-73...............................................

Table 3-25: Real Time Clock Functions 3-75.......................

Table 4-1: Equipment Required 4-2.............................

Table 4-2: Settings for Shape Factor Check 4-5....................

Table 4-3: Settings for the Noise Sidebands Check 4-7..............

Table 4-4: Front Panel Span Accuracy Settings 4-8................

Table 4-5: Maximum Range in 10 dB/Div 4-11.....................

Table 4-6: Resolution Bandwidth Filter Display Dynamic

Range Settings 4-12........................................

T able 4-7: Sensitivity Settings at 110 MHz 4-13.....................

Table 4-8: Sensitivity Settings at 1800 MHz 4-14....................

T able 4-9: Sensitivity Settings at 2.15 GHz 4-15....................

Table 5-1: Test Equipment 5-2..................................

Table 5-2: Power Supply Tolerances 5-7..........................

Table 5-3: Power Supply Tolerances 5-10..........................

Table 5-4: Correction Bit Values 5-39.............................

Table 5-5: Television Channels 5-40..............................

Table 6-1: Relative Susceptibility to Static Discharge Damage 6-2....

Table 6-2: Cal Debug Messages and Meanings 6-9.................

Table 6-3: Servicing Tools for Boards With Surface

Mounted Components 6-15..................................

viii

2715 Spectrum Analyzer Service Manual

General Safety Summary

Review the following safety precautions to avoid injury and prevent damage to this product or any products connected to it. To avoid potential hazards, use this product only as specified.

Only qualified personnel should perform service procedures.

While using this product, you may need to access other parts of the system. Read the General Safety Summary in other system manuals for warnings and cautions related to operating the system.

ToAvoidFireor

Personal Injury

Use Proper Power Cord. Use only the power cord specified for this product and certified for the country of use.

Connect and Disconnect Properly. Do not connect or disconnect probes or test leads while they are connected to a voltage source.

Ground the Product. This product is grounded through the grounding conductor of the power cord. To avoid electric shock, the grounding conductor must be connected to earth ground. Before making connections to the input or output terminals of the product, ensure that the product is properly grounded.

Observe All Terminal Ratings. To avoid fire or shock hazard, observe all ratings and marking on the product. Consult the product manual for further ratings information before making connections to the product.

The common terminal is at ground potential. Do not connect the common terminal to elevated voltages.

Do not apply a potential to any terminal, including the common terminal, that exceeds the maximum rating of that terminal.

Do Not Operate Without Covers. Do not operate this product with covers or panels removed.

Use Proper Fuse. Use only the fuse type and rating specified for this product.

Avoid Exposed Circuitry. Do not touch exposed connections and components

when power is present.

Wear Eye Protection. Wear eye protection if exposure to high-intensity rays or laser radiation exists.

Do Not Operate With Suspected Failures. If you suspect there is damage to this product, have it inspected by qualified service personnel.

Do Not Operate in Wet/Damp Conditions.

Do Not Operate in an Explosive Atmosphere.

2715 Spectrum Analyzer Service Manual

General Safety Summary

Keep Product Surfaces Clean and Dry.

Provide Proper Ventilation. Refer to the manual’s installation instructions for

details on installing the product so it has proper ventilation.

Symbols and Terms

Terms in this Manual. These terms may appear in this manual:

WARNING. Warning statements identify conditions or practices that could result in injury or loss of life.

CAUTION. Caution statements identify conditions or practices that could result in damage to this product or other property.

Terms on the Product. These terms may appear on the product:

DANGER indicates an injury hazard immediately accessible as you read the marking.

WARNING indicates an injury hazard not immediately accessible as you read the marking.

CAUTION indicates a hazard to property including the product.

Symbols on the Product. The following symbols may appear on the product:

WARNING

High Voltage

Protective Ground

(Earth) Terminal

CAUTION

Refer to Manual

Double

Insulated

2715 Spectrum Analyzer Service Manual

Service Safety Summary

Only qualified personnel should perform service procedures. Read this Service Safety Summary and the General Safety Summary before performing any service

procedures.

Do Not Service Alone. Do not perform internal service or adjustments of this product unless another person capable of rendering first aid and resuscitation is present.

Disconnect Power. To avoid electric shock, switch off the instrument power, then disconnect the power cord from the mains power.

Use Caution When Servicing the CRT. To avoid electric shock or injury, use extreme caution when handling the CRT. Only qualified personnel familiar with CRT servicing procedures and precautions should remove or install the CRT.

CRTs retain hazardous voltages for long periods of time after power is turned off. Before attempting any servicing, discharge the CRT by shorting the anode to chassis ground. When discharging the CRT, connect the discharge path to ground and then the anode. Rough handling may cause the CRT to implode. Do not nick or scratch the glass or subject it to undue pressure when removing or installing it. When handling the CRT, wear safety goggles and heavy gloves for protection.

Use Care When Servicing With Power On. Dangerous voltages or currents may exist in this product. Disconnect power, remove battery (if applicable), and disconnect test leads before removing protective panels, soldering, or replacing components.

To avoid electric shock, do not touch exposed connections.

X-Radiation. To avoid x-radiation exposure, do not modify or otherwise alter the high-voltage circuitry or the CRT enclosure. X-ray emissions generated within this product have been sufficiently shielded.

2715 Spectrum Analyzer Service Manual

Service Safety Summary

xii

2715 Spectrum Analyzer Service Manual

Preface

This manual contains service information for the 2715 Spectrum Analyzer. The service information is located in two volumes. Volume 1 contains the maintenance procedures and parts lists. Volume 2 contains the component locators and schematic diagrams.

This manual is divided into the following sections.

H Section 1: Specifications, contains characteristic tables detailing Electrical

Characteristics, Mechanical Characteristics, and Environmental Character-

istics.

H Section 2: Operating Information, contains information on how to install and

operate the product.

H Section 3: Theory of Operation, contains both a general and detailed circuit

description of the various modules that make up the instrument.

H Section 4: Performance Verification, is a procedure to ensure, when passed,

that the product operates properly and meets its advertised performance

levels.

H Section 5: Adjustment Procedures, is a procedure to ensure that, when

performed, the product can meet the performance levels for characteristics

listed in Section 1, Specifications.

H Section 6: Maintenance, contains instructions for removal and replacement

of internal modules or components.

H Section 7: Options, describes all options available for this instrument.

H Section 8: Replaceable Electrical Parts, is a list of replaceable assemblies

and electrical components.

H Section 9: Diagrams, Refer to the 2715 Spectrum Analyzer Service Manual

Volume 2.

H Section 10: Replaceable Mechanical Parts, is a list of replaceable assemblies

and mechanical components. Exploded-view illustrations are included to

relate assemblies to the parts list.

The following manuals are also available for the 2715 Spectrum Analyzer.

H 2715 User Manual provides information necessary to operate the 2715

Spectrum Analyzer.

H 2714 & 2715 Programmer Manual includes all GPIB commands, queries,

and responses for the instrument.

H The Cable TV RF Measurement Software Manual describes how to use the

Cable TR RF Measurements Software, a test system that measures cable TV

parameters.

2715 Spectrum Analyzer Service Manual

xiii

Preface

Contacting Tektronix

Phone 1-800-833-9200*

Address Tektronix, Inc.

Department or name (if known) 14200 SW Karl Braun Drive P.O. Box 500 Beaverton, OR 97077 USA

Web site www.tektronix.com

Sales support 1-800-833-9200, select option 1*

Service support 1-800-833-9200, select option 2*

Technical support Email: techsupport@tektronix.com

1-800-833-9200, select option 3*

6:00 a.m. -- 5:00 p.m. Pacific time

* This phone number is toll free in North America. After office hours, please leave a

voice mail message. Outside North America, contact a Tektronix sales office or distributor; see the Tektronix web site for a list of offices.

xiv

2715 Spectrum Analyzer Service Manual

Specifications

This section lists the electrical, physical, and environmental characteristics of the spectrum analyzer, specifies the performance requirements for those characteristics, and provides supplementary information.

Electrical Characteristics

Unless otherwise stated, the following tables of electrical characteristics and features apply to the spectrum analyzer after a 15 minute warm-up period (within the environmental limits) and after all normalization procedures have been carried out.

Information in the Performance Requirement column of Tables 1--2 through 1--8 is guaranteed and verifiable unless otherwise noted. Supplemental Information is intended to further explain a characteristic, its performance requirement, or to describe characteristic performance that is impractical to verify. Supplemental Information is not guaranteed and may not be supported by a performance check procedure.

Changes to a characteristic because of the addition of an option are included in Table 1--7.

2715 Spectrum Analyzer Service Manual

1- 1

Specifications

Table 1- 1: CATV Characteristics

Characteristic Description

Input Configuration

All except Option 50 75 Ω Female F connector

Option 50 50 Ω Type N connector

Channel Selection The visual and aural carriers are displayed when the channel number is entered, or

either [ y ] or [ b ] next to [CHAN/FREQ] is pressed

Tune Configuration STD (73.603), HRC (73.605), IRC (73.612), and Custom

Channel Range 0to999

Frequency Range (except Opt 50 and Opt 75)

Frequency Range (Opt 50 and Opt 75)

Visual Carrier Frequency Measurement

Method Internal Counter

Resolution 1Hz

Accuracy 5 × 10-7× Carrier Frequency ±10 Hz, ±1 Least Significant Digit

1MHzto1.8GHz2, Preamp limited to 600 MHz

1 MHz to 2.15 GHz2, Preamp limited to 600 MHz

Accuracy is dependent on the accuracy of the spectrum analyzer — see Frequency Accuracy in Table 1--2.

@ 55.25 MHz (Ch 2) worst case is ±38 Hz @ 325.25 MHz (Ch 41) worst case is ±173 Hz @ 643.25 MHz (Ch 94) worst case is ±332 Hz

Visual-to-Aural Carrier Frequency Measurement Aural carrier measured relative to the visual carrier

Method Internal Counter

Difference Range 1 MHz to 10 MHz3for an amplitude difference of ≤30 dB and aural C/N ≥15 dB

(300 kHz RBW)

Resolution 1Hz

Accuracy ±15 Hz for visual-to-aural carrier difference ≤8MHz

Visual Carrier Peak Level Measurement Absol ute peak amplitude of visual carrier measured with PREAMP OFF

Accurate Frequency and Amplitude

Visual carrier frequency measurement Visual-to-aural carrier frequency measurement Visual carrier peak level measurement Visual-to-aural carrier level difference measurement

Accurate Amplitude Only Visual carrier peak level measurement

Visual-to-aural carrier level difference measurement

Fast Amplitude Only Carrier amplitudes are measured using marker values in 10 dB/div vertical scale

Amplitude Range --18 dBmV to +58.8 dBmV4for visual C/N ≥30 dB (300 kHz RBW)

Configured using Cable TV RF Measurements Software.

Dependent on selected channel table. Frequencies above 1.8 GHz are not supported by the Cable TV RF Measurements Software.

Dependent on selected channel table.

Total input power (all signals included) cannot exceed +70 dBmV.

1- 2

2715 Spectrum Analyzer Service Manual

Specifications

Table 1- 1: CATV Characteristics (Cont.)

Characteristic Description

Frequency Range 15 to 1015 MHz

Resolution 0.1 dB

Absolute Accuracy ±2.5 dB for visual C/N ≥30 dB (300 kHz RBW) and for FM signal C/N ≥33 dB (100

kHz RBW) assumes flatness corrections are present

Relative Accuracy ±0.5 dB relative to adjacent channel

±1.2 dB relative to all other channels

Visual-to-Aural Carrier Level Difference Measurement

Difference Range 0 to 30 dB for aural C/N ≥15 dB (300 kHz RBW)

Resolution 0.1 dB

Accuracy ±0.75 dB for aural C/N ≥15 dB (300 kHz RBW)

Averaged Power (Typical) Averaged amplitude measured with preamp off

Accuracy ±2.5 dB for input levels above --30 dBmV, up to +37 dBmV (multichannel) or

Resolution 0.1 dB

Modulation Depth Measurement (Typical)

AM Range 50% to 95%

Resolution 0.1%

Accuracy ±2% for visual C/N ≥40 dB (300 kHz RBW)

HUM/LFD Measurement (Typical) Power line frequency is measured on an unmodulated visual carrier, and low

AM Range 1% to 10% peak-to-peak

Resolution 0.1%

Accuracy ±1% for Hum ≤5% and visual C/N ≥25 dB (300 kHz RBW)

Carrier-to-Noise (C/N) Measurement (Typical)

Optimum Input Range See Figure 1--1 on page 1--7

Maximum Range See Figure 1--1 on page 1--7

Resolution 0.3 dB

Accuracy See Figure 1--1 on page 1--7

In-Service C/N (typical) Noise density is measured at 2 MHz offset (by default) from visual carrier during

Optimum Input Range See Figure 1--1 on page 1--7

Maximum Range See Figure 1--1 on page 1--7

Resolution 0.3 dB

Aural carrier level measured relative to the visual carrier

+52 dBmV (preselector in use)

Percent AM measured from sync tip to lowest white level found in 10 sweeps (the VITS line is used if it is defined in the channel table)

frequency disturbance (LFD) is measured on the modulated carrier

±2% for Hum <10% and visual C/N ≥25 dB (300 kHz RBW)

Default noise floor is a normalized 4 MHz bandwidth measured relative to the visual carrier peak

quiet lines in the vertical interval, then normalized to 4 MHz BW and expressed as dBc

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Specifications

Table 1- 1: CATV Characteristics (Cont.)

Characteristic Description

Accuracy See Figure 1--1 on page 1--7

Desired-to-Undesired Ratio (Typical) Channel averaged power is divided by total noise plus distortion in the channel

Resolution 0.1 dB

Accuracy ±2 dB within the limits shown in Figure 1--6 on page 1--9

CTB Measurement (Typical) Composite triple beat (CTB) is measured relative to the visual carrier peak according

to the NCTA recommended spectrum analyzer settings — SINGLE-SWEEP mode does not use all the NCTA recommended settings

Maximum Range See Figure 1--2 on page 1--7

Resolution 0.3 dB

Accuracy See Figure 1--2 on page 1--7

Digital Channel CTB (Typical) Measured relative to the averaged power of the test channel

Resolution 0.3 dB

Accuracy ±2 dB within the limits shown in Figure 1 --8 on page 1 --10

CSO Measurement (Typical)

Optimum Input Range See Figure 1--3 on page 1--8

Maximum Range See Figure 1--3 on page 1--8

Resolution 0.3 dB

Accuracy See Figure 1--3 on page 1--8

In-Service CSO (Typical) CSO products are measured per NCTA recommendations during quiet lines in the

Optimum Input Range See Figure 1--4 on page 1--8

Maximum Range See Figure 1--4 on page 1--8

Resolution 0.3 dB

Accuracy See Figure 1--4 on page 1--8

Digital Channel CSO (Typical) Measured relative to the averaged power of the test channel

Resolution 0.3 dB

Accuracy ±2.0 dB within the limits shown in Figure 1 --7 on page 1--10

Frequency Response Measurement (Typical)

Reference Trace Storage (Nonvolatile)

Range 5 dB/div, fixed

Resolution 0.2 dB

Trace Flatness Accuracy ±0.75 dB

Composite second order (CSO) is measured relative to the visual carrier peak according to the NCTA recommended spectrum analyzer settings — SINGLESWEEP and CONTINUOUS modes do not use all the NCTA recommended settings

vertical interval, then expressed as dBc

For fixed-amplitude scrambling or no scrambling, system amplitude variations (flatness) are measured relative to a reference trace (stored during the frequency response reference setup)

Up to 10 traces with spectrum analyzer states

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2715 Spectrum Analyzer Service Manual

Specifications

Table 1- 1: CATV Characteristics (Cont.)

Characteristic Description

Carrier Survey Absolute peak amplitude of each visual carrier measured and each associated aural

carrier level measured relative to the measured visual carrier for the selected channels — characteristics are identical to the frequency (visual and aural) and level measurements (frequency is counted only if ACCURATE FREQUENCY AND AMPL is on)

Accurate Frequency and Amplitude

Accurate Amplitude Only Visual carrier peak level measurement

Fast Amplitude Only Carrier amplitudes are measured using marker values in 10 dB/div vertical scale

Visual Carrier

Amplitude Range --18 dBmV to +58.8 dBmV5for C/N ≤30 dB (300 kHz RBW)

Frequency Range 15 MHz to 1015 MHz

Resolution 0.3 dB

Absolute Accuracy ±2.7 dB for visual C/N ≥30 dB (300 kHz RBW) and for FM signal C/N ≥33 dB (100

Relative Accuracy ±0.8 dB relative to adjacent channel

Aural Carrier

Difference Range 0to30dBforC/N≥15 dB (300 kHz RBW)

Resolution 0.3 dB

Accuracy ±1.1 dB for C/N ≥15 dB (300 kHz RBW)

Aural <FM> Deviation (Typical) Peak FM deviation measured for the selected channel

Range 10 kHz to 50 kHz, usable to 80 kHz

Accuracy ±4 kHz

Cross Modulation (Typical) The third order distortion at the horizontal sync frequency (AM) measured on the

Range 48 dB

Resolution 0.1 dB

Accuracy ±2 dB for cross modulation <36 dB

Listen (Typical) The aural carrier for the selected channel is demodulated

Output Speaker or headphones with volume control

Demodulation Type FM

Sweep Displays instantaneous peak FM deviation

Total input power (all signals included) cannot exceed +70 dBmV.

Visual carrier frequency measurement Visual-to-aural carrier frequency measurement Visual carrier peak level measurement Visual-to-aural carrier level difference measurement

Visual-to-aural carrier level difference measurement

kHz RBW) assumes flatness corrections are present

±1.5 dB relative to all other channels

unmodulated visual carrier, as corrected to the NCTA recommended synchronous square wave modulation procedure

±3 dB for cross modulation <48 dB

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Specifications

Table 1- 1: CATV Characteristics (Cont.)

Characteristic Description

View Picture (Typical) The visual carrier, NTSC or PAL format depending on the selected channel, is

demodulated

View Modulation (Field) (Typical) One video field of the selected channel video is displayed

View Modulation (Line) (Typical) The VITS line is displayed — if no VITS line is specified in the channel table, line 17

is displayed

TV Line Selection Selectable using the FREQ/M KRS knob during View Line Modulation function

Line Format NTSC or PAL

Line Range 1 to 525 (NTSC), 1 to 625 (PAL)

Sweep Time 10 s/div

In-Channel Response

Range ±3 dB (the auto test is run in 1 dB/div)

Resolution 0.1 dB

Accuracy ±0.5 dB, Auto mode

±0.8 dB, Interactive mode

Adjacent Channel Leakage (Typical) Averaged power in adjacent channel(s) is divided by averaged power for the test

channel

Resolution 0.1 dB

Accuracy ±2.0 dB within limits shown in Figure 1--5 on page 1--9

In-Service In-Channel Response (Typical) Standard vertical interval test signal (line sweep, ghost-canceller, multiburst) is

measured within gate which excludes active video; result is expressed as dB P-P

Resolution 0.2 dB

Accuracy ± 0.5 dB assuming test signal is flat at head end

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2715 Spectrum Analyzer Service Manual

-- 9 0

-- 8 0

-- 7 0

Specifications

-- 6 0

Measurement

Minimum C/N

measurements

C/N

Limit (dBc)

for gated

-- 5 0

-- 4 0

-- 3 0

-- 2 0

-- 1 0

Minimum signal level for gated measurement (at 1000 MHz)

Minimum signal level for gated measurement (to 500 MHz)

-- 2 0

-- 3 0

--100 102030 4050 6070

VISUAL CARRIER PEAK (dBmV)

Figure 1- 1: Typical Accuracy Limits for Carrier-to-Noise Measurement

-- 9 0

-- 8 0

-- 7 0

± 4dBto500MHz

± 2dBto500MHz ± 4 dB at 1000 MHz ± 2 dB at 1000 MHz

Note: 60 channel flat system

± 4dBto500MHz(Note1) ± 2dBto500MHz(Note1)

-- 6 0

CTB

Measurement

Limit (dBc)

-- 5 0

-- 4 0

-- 3 0

-- 2 0

-- 1 0

Minimum signal level for gated measurement (at 1000 MHz)

Minimum signal level for gated measurement (to 500 MHz)

-- 2 0

-- 3 0

--100 102030 4050 6070

VISUAL CARRIER PEAK (dBmV)

Figure 1- 2: Typical Accuracy Limits for CTB Measurem ent

2715 Spectrum Analyzer Service Manual

± 4dBto500MHz(Note2) ± 2dBto500MHz(Note2)

± 4 dB at 1000 MHz (Note 2) ± 2 dB at 1000 MHz (Note 2)

Note 1 Approximate extended limits if preselector is used and mixer input level is set to --20 dBm.

Note 2 Normal limits without preselector and mixer input level set to default setting of --30 dBm in a 60 channel flat system.

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Specifications

-- 9 0

-- 8 0

-- 7 0

-- 6 0

CSO

Measurement

Limit (dBc)

-- 5 0

-- 4 0

-- 3 0

-- 2 0

-- 1 0

Minimum signal level for gated measurement (at 1000 MHz)

Minimum signal level for gated measurement (to 500 MHz)

-- 2 0

-- 3 0

--100 102030 40506070

VISUAL CARRIER PEAK (dBmV)

Figure 1- 3: Typical Accuracy Limits for Nongated CSO Measurement

-- 9 0

-- 8 0

-- 7 0

± 4dBto500MHz(Note1)

± 2dBto500MHz(Note1)

± 4dBto500MHz(Note2) ± 2dBto500MHz(Note2) ± 4 dB at 1000 MHz (Note 2) ± 2 dB at 1000 MHz (Note 2)

Note 1 Approximate extended limits if preselector is used and mixer input level is set to --20 dBm.

Note 2 Normal limits without preselector and mixer input level set to default setting of --30 dBm. in a 60 channel flat system

-- 6 0

CSO

Measurement

Limit (dBc)

-- 5 0

-- 4 0

-- 3 0

-- 2 0

-- 1 0

Minimum signal level for gated measurement (at 1000 MHz)

Minimum signal level for gated measurement (to 500 MHz)

-- 2 0

-- 3 0

--100 102030 40506070

VISUAL CARRIER PEAK (dBmV)

Figure 1- 4: Typical Accuracy Limits for Gated CSO Measurement

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± 4dBto500MHz(Note1)

± 2dBto500MHz(Note1)

± 4dBto500MHz(Note2) ± 2dBto500MHz(Note2) ± 4 dB at 1000 MHz (Note 2) ± 2 dB at 1000 MHz (Note 2)

Note 1 Approximate extended limits if preselector is used and mixer input level is set to --20 dBm.

Note 2 Normal limits without preselector and mixer input level set to default setting of --30 dBm in a 60 channel flat system.

2715 Spectrum Analyzer Service Manual

-- 6 5

-- 5 5

Specifications

To 500 MHz

500 MHz to 1000 MHz

Measurement

Limit (dBc)

-- 4 5

-- 3 5

-- 2 5

-- 2 0

--10 0 1020 30 40 506070

INPUT LEVEL (dBmV) FOR SINGLE-SIGNAL TEST ENVIRONMENT

Figure 1- 5: Typical ACL Measurement Limits for 2 dB Accuracy

To 500 MHz using preselector

500 MHz to 1000 MHz using preselector

To 500 MHz in 60-channel flat system dominated by analog signals 10 dB stronger than average power of channel under test

500 MHz to 1000 MHz in 60-channel flat system dominated by analog signals 10 dB stronger than average power of channel under test

Measurement

Limit (dB)

-- 2 0

--10 0 1020 30 40 506070

CHANNEL UNDER TEST INPUT LEVEL (dBmV)

Figure 1- 6: Typical D/U Measurement Range Limits for 2 dB Accuracy

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Specifications

To 500 MHz using preselector

500 MHz to 1000 MHz using preselector

To 500 MHz in 60-channel flat system dominated by analog signals 10 dB stronger than average power of channel under test

500 MHz to 1000 MHz in 60-channel flat system dominated by analog signals 10 dB stronger than average power of channel under test

-- 6 5

-- 5 5

Measurement

Limit (dBc)

-- 4 5

-- 3 5

-- 2 5

-- 2 0

--10 0 1020 30 40 506070

INPUT LEVEL (dBmV)

Figure 1- 7: Typical Digital Signal CSO Measurement Range Limit for 2 dB Accuracy

To 500 MHz using preselector

500 MHz to 1000 MHz using preselector

To 500 MHz in 60-channel flat system dominated by analog signals 10 dB stronger than average power of channel under test

500 MHz to 1000 MHz in 60-channel flat system dominated by analog signals 10 dB stronger than average power of channel under test

-- 6 5

-- 5 5

Measurement

Limit (dBc)

-- 4 5

-- 3 5

-- 2 5

-- 2 0

--10 0 1020 30 40 506070

INPUT LEVEL (dBmV)

Figure 1- 8: Typical Digital Signal CTB Measurement Range Limit for 2 dB Accuracy

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2715 Spectrum Analyzer Service Manual

Specifications

Table 1- 2: Frequency-Related Characteristics

Characteristic Performance Requirement Supplemental Information

Channel Tuned with keypad, [CHAN/FREQ] [ y ],

or [CHAN/FREQ] [ b ],accordingtothe selected channel table

Frequency

Range All except Option 50 and Option 75:

9 kHz to 1.8 GHz Option 50 and Option 75: 9 kHz to

2.15 GHz

Accuracy 5 × 10

Drift

Long Term (One Year) ±2 PPM/year

Short Term (SPAN/DIV ≤20 kHz) All except Option 50 and Option 75:

Readout Resolution 1 kHz or 1 Hz (counter readout), menu

Frequency Span/Div

Range Using

Accuracy/Linearity Within 3% Measured over the center 8 divisions

Flatness (Relative to the Reference Level at 100 MHz)

-- 7

of center frequency ±10 Hz ±1

least significant digit

≤400 Hz up to 1.8 GHz Option 50 and Option 75: 500 Hz above

1.8 GHz

All instruments: ±2dB9KHzto1.8GHz Option 50 and Option 75: ±3 dB above

1.8 GHz

Tuned with keypad, [CHAN/FREQ] [ y ], [CHAN/FREQ] [ b ], FREQ/MARKERS knob, UTIL menu, or MKR/FREQ menu

Assumes zero drift since last normalization procedure

With frequency corrections enabled

selectable

[SPAN/DIV] [ y ] and [SPAN/DIV] [ b ] buttons, selections in a 1--2--5 sequence Using the keypad or UTIL menu, select any value from 100 MHz/div to 1 kHz/div. In MAXSPAN, 180 MHz/div (All except Option 50 and Option 75) or 215 MHz/div (Option 50 and Option 75) In ZERO SPAN, 0 Hz/div

Measured with 10 dB of RF Attenuation and PREAMP off

Flatness is affected by: H Input voltage standing-wave ratio

(VSWR)

H Gain variation H Mixer conversion

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Specifications

Table 1- 2: Frequency-Related Characteristics (Cont.)

Characteristic Supplemental InformationPerformance Requirement

Residual FM

With SPAN/DIV ≤20 kHz All except Option 50 and Option 75:

≤100 Hz peak-to-peak total excursion in 20 ms up to 1.8 GHz Option 50 and Option 75: ≤120 Hz peak-to-peak total excursion in 20 ms (above 1.8 GHz)

With SPAN/DIV >20 kHz All except Option 50 and Option 75:

≤2 kHz peak-to-peak total excursion in 20 ms up to 1.8 GHz Option 50 and Option 75: ≤2.4 KHz peak-to-peak total excursion in 20 ms above 1.8 GHz

Resolution Bandwidth (6 dB down) Resolution bandwidth selections are:

Shape Factor (60 dB/6 dB) 7:1 or less for all resolution bandwidths

≤1MHz

Noise Sidebands All except Option 50 and Option 75:

≤--70 dBc at 30X Resolution Bandwidth for all resolution bandwidths ≤100 kHz Option 50 and Option 75: ≤–69 dBc at 30X Resolution Bandwidth for all resolution bandwidths ≤100 kHz

Video Filter Reduces video bandwidth to about 1% of

Short term, after 1 hr warm-up, and with PHASELOCK in AUTO mode

5 MHz, 1 MHz, 300 kHz, 100 kHz, 30 kHz, 10 kHz, 3 kHz, 1 kHz, and 300 Hz for the spectrum analyzer

the selected resolution bandwidth; or one of 12 video filters (3 Hz, 10 Hz, 30 Hz, 100 Hz, 300 Hz, 1 kHz, 3 kHz, 10 kHz, 30 kHz, 100 kHz, 300 kHz, or WIDE) can be selected from the UTIL menu

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