Tektronix 2706 User manual

Instruction Manual
2706
RF Preselector
070-8545-02
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

Copyright ©Tektronix, Inc. All rights reserved.
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 replacement 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 the 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 designated by Tektronix, with
shipping charges prepaid. Tektronix shall pay for the return of the product to Customer if the shipment is to a
location within the country in which the Tektronix service center is located. Customer 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 WARRANTY 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 WARRANTY. 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.

2706 RF Preselector i
Contents
List of Figures ii. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
List of Tables ii. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Preface iii. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Welcome iii. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
About this Manual iii. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
What you Need to Know iv. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
How to Use This Manual iv. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Manual Conventions v. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Contacting Tektronix v. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
General Safety Summary vii. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Service Safety Summary ix. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
User Information
Introduction 1–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Preselector Controls and Connectors 1–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
What you Need to Use the Preselector 1–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Using the Preselector 2–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Manual Operation 2–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Remote Operation 2–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
GPIB Common and Device Commands 2–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Service Information
Performance Verification 3–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Performance Verification Procedure 3–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Troubleshooting 3–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Replacing the Fuse 3–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Applications 4–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
EMI Testing 4–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Susceptibility Testing 4–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Benchtop Analysis 4–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Appendixes
Appendix A: Specifications A–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Electrical Specifications A–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Mechanical Specifications A–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Environmental Specifications A–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Certifications and Compliances A–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Appendix B: Using the GPIB Interface B–1. . . . . . . . . . . . . . . . . . . . . . . . .
Interface Compatibility B–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Controller Commands B–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Sample Program B–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
GPIB Commands B–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Contents
ii 2706 RF Preselector
Appendix C: Options C–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Power Cord Options C–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Option 01 C–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Appendix D: Parts List D–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Standard Accessories D–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Options D–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Appendix E: Repackaging for Shipment E–1. . . . . . . . . . . . . . . . . . . . . . . .
List of Figures
Figure 1–1: The Preselector’s Front Panel 1–1. . . . . . . . . . . . . . . . . . . . . .
Figure 1–2: The Preselector’s Rear Panel 1–2. . . . . . . . . . . . . . . . . . . . . . .
Figure 3–1: The fuse location 3–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
List of Tables
Table 2–1: Commands Supported by the Preselector 2–3. . . . . . . . . . . . .
Table A–1: Preselector Band Related Specifications A–1. . . . . . . . . . . . . .
Table A–2: Certifications and compliances A–3. . . . . . . . . . . . . . . . . . . . .

2706 RF Preselector iii
Preface
This preface describes the features of the Tektronix 2706 stepped Radio
Frequency Preselector. It also tells you how to use this manual and what you
should know before you use the Preselector.
Welcome
Congratulations on your purchase of a 2706 RF Preselector. This instrument
improves the flexibility and accuracy of your spectrum analyzer measurements,
and is especially useful for EMI applications.
Some of the outstanding characteristics of the Preselector are:
HMultiple filters –the Preselector has 7 bandpass filter steps covering the
range from 9 kHz to 1000 MHz, and a high-pass filter covering the range
from 1000 MHz to 1800 MHz.
HReduced distortion –the Preselector limits potentially distorting input to a
spectrum analyzer by attenuating signals outside the frequency range of
interest.
HIncreased broadband dynamic range –the Preselector increases sensitivity to
low-level signals by attenuating strong signals outside the frequency range of
interest.
HManual or remote operation –you can operate the Preselector using its
front-panel controls or a GPIB equipped controller or computer.
HBypass mode –you can remove the Preselector from the testing circuit
without disconnecting it.
HConvenient installation –the Preselector mounts below Tektronix 271X-
Series Spectrum Analyzers with the optional mounting plate and rigid
coaxial cable assembly (see the Parts List in Appendix D).
About this Manual
This manual contains the following sections:
HChapter 1, “Introduction,”lists the features of the Tektronix 2706 RF
Preselector and what you need to use the Preselector.
HChapter 2, “Using the Preselector,”describes how to control the Preselector
manually or using a GPIB controller.

Preface
iv 2706 RF Preselector
HChapter 3, “Performance Verification,”tells you how to check that the
Preselector is operating within specification, and how to troubleshoot
problems with the Preselector.
HChapter 4, “Applications,”describes ways you can use the Preselector.
HAppendix A, “Specifications,”lists the electrical, environmental, and
mechanical specifications of the Preselector.
HAppendix B, “Using the GPIB Interface,”describes in detail the commands
you use to operate the Preselector remotely.
HAppendix C, “Options,”describes in detail the power cord and extended
service options of the Preselector.
HAppendix D, “Parts List,”lists the part numbers of the standard and optional
Preselector accessories.
HAppendix E, “Repackaging for Shipment,”describes how to package the
Preselector for shipment.
What you Need to Know
To use this manual, you need to know two things:
HHow to operate a spectrum analyzer.
HThe basic concepts of signal analysis.
If you plan to operate the Preselector remotely, you also need to know how to
use your GPIB controller.
How to Use This Manual
This manual is designed to help you learn to use the Preselector quickly and
easily.
Follow these steps to use this manual:
1. Read the rest of this preface.
2. Read Chapter 1, “Introduction,”for an overview of the Preselector’s features.
3. Follow the instructions in Chapter 2, “Using the Preselector,”to learn how to
use the Preselector.
4. Use Chapter 3, “Performance Verification,”and Appendix A, “Specifica-
tions,”to check that the Preselector is working correctly.

Preface
2706 RF Preselector v
5. Use Chapter 4, “Applications,”to see ways you can use the Preselector.
6. If you plan to operate the Preselector from a GPIB controller, use Appendix
B, “Using the GPIB Interface.”
Manual Conventions
To make this manual easier to use, text is shown in several type styles:
HReferences to other manuals or documents are in italics: ANSI/IEEE Std
488.2–1987.
HCommand names, and panel and cable labels are in bold type.
HText that you type into a GPIB controller is in single space type.
Contacting Tektronix
Product
Support For questions about using Tektronix measurement products, call toll free in North America:
1-800-833-9200
6:00 a.m. –5:00 p.m. Pacific time
Or contact us by e-mail:
[email protected]
For product support outside of North America, contact your
local Tektronix distributor or sales office.
Service
support Tektronix offers a range of services, including Extended Warranty Repair and Calibration services. Contact your local
Tektronix distributor or sales office for details.
For a listing of worldwide service centers, visit our web site.
Toll-free
Number In North America: 1-800-833-9200
An operator can direct your call.
Postal
Address Tektronix, Inc.
Department or name (if known)
P.O. Box 500
Beaverton, OR 97077
USA
Web site www.tektronix.com

Preface
vi 2706 RF Preselector

2706 RF Preselector vii
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.
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 markings on the product. Consult the product manual for further ratings
information before making connections to the product.
Connect the ground lead of the probe to earth ground only.
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.
Do Not Operate With SuspectedFailures. If you suspect there is damage to this
product, have it inspected by qualified service personnel.
Do Not Operate in Wet/DampConditions.
Do Not Operate in an Explosive Atmosphere.
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.
To Avoid Fire or
Personal Injury

General Safety Summary
viii 2706 RF Preselector
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:
CAUTION
Refer to Manual WARNING High Voltage Double
Insulated ProtectiveGround
(Earth) Terminal Not suitable for
connectionto
thepublic telecom-
municationsnetwork
Symbols and Terms

2706 RF Preselector ix
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 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.

Service Safety Summary
x 2706 RF Preselector

User Information

2706 RF Preselector 1–1
Introduction
This chapter describes the features of the Tektronix 2706 RF Preselector and
what you need to use it.
Preselector Controls and Connectors
This section presents a brief tour of the Preselector controls and connectors.
The Preselector front panel has the following controls:
Figure 1–1: The Preselector’s Front Panel
HPOWER switch –this turns instrument operating power on (1) or off (0).
HREMOTE/LOCAL switch –this transfers control of the Preselector from
remote (GPIB controlled) mode to local (manually controlled) mode. The
REMOTE LED lights when remote mode is selected.
HBYPASS switch –this disconnects all Preselector filters so that the entire RF
signal is sent directly to the spectrum analyzer. The BYPASS LED lights
when bypass mode is selected.
HBAND SELECT <- and -> switches –these select the signal routing band from
among 7 bandpass filters and a high-pass filter. An LED lights on the front
panel to indicate the selected filter.
HRF INPUT –this connects the Preselector to the signal source using a type N
plug.
HRF OUTPUT –this connects the preselected output to the spectrum analyzer
using a type N plug.
Front Panel

Introduction
1–22706 RF Preselector
The Preselector rear panel has these connectors and switches:
Figure 1–2: The Preselector’s Rear Panel
HIEEE STD 488 PORT –this connects the Preselector to a controller.
HADDRESS switch –this selects the GPIB address for the Preselector.
HPOWER –this plugs the Preselector into the AC power source
(90–250 VAC, 48–63 Hz).
What you Need to Use the Preselector
To use the Preselector, you need the following:
Han RF signal source, such as an antenna or test device (Chapter 4, “Applica-
tions,”describes example setups)
Ha spectrum analyzer, such as the Tektronix 271X–, 278X–, or 279X–Series
(or equivalent)
Htwo RF connecting cables with type N connectors or adapters
If you will operate the Preselector remotely, you will also need the following:
Han IEEE STD 488 GPIB 24-pin cable with a D-type shell (Tektronix part
number 012–0991–00)
Han IEEE–488 GPIB controller, or an IBM PC/AT or compatible 80386 (or
better) personal computer with a National Instruments PCII/IIA type card
and communications drivers
Ha copy of the Tektronix S26EM12 Commercial EMI Test Software (optional)
Rear Panel

2706 RF Preselector 2–1
Using the Preselector
This chapter describes how to operate the Preselector manually or with a GPIB
controller.
Manual Operation
This section tells you how to use the Preselector manually by using its front-pan-
el controls.
Use the Preselector as follows:
1. Plug the Preselector into a power source (90–250 VAC, 48–63 Hz).
2. Connect the spectrum analyzer input to the RF OUTPUT connector on the
Preselector’s front panel.
3. Turn on the Preselector. The front-panel LEDs will light sequentially. When
the BYPASS LED lights, the unit is ready to use.
NOTE. If any of the LEDs do not light, refer to Chapter 3, Performance
Verification.
4. Turn on the spectrum analyzer.
5. Use the BAND SELECT <- and -> switches to select the filter you want. The
Preselector will pass the frequency range printed above and below the lit
LED.
6. Connect the RF source to the RF INPUT connector on the Preselector’s front
panel.
The Preselector is now ready for operation.
Remote Operation
This section tells you how to operate the Preselector remotely with a controller
or computer that uses the IEEE Standard 488.2-1987 (GPIB) interface.
The smallest GPIB network that you can use is a Preselector and a controller;
you will also probably connect a spectrum analyzer to the network.

Using the Preselector
2–22706 RF Preselector
NOTE. To operate the Preselector remotely, you need to consult the documenta-
tion for your controller to determine how to send commands and interpret
received messages in your controller’s programming language.
Use the Preselector remotely as follows:
1. Plug the Preselector into a power source (90–250 VAC, 48–63 Hz).
2. Connect the spectrum analyzer input to the RF OUTPUT connector on the
Preselector’s front panel.
3. Connect a GPIB 24-pin cable to the IEEE STD 488 PORT connector on the
rear panel of your Preselector and to the GPIB network.
4. Verify that the bus address on the rear-panel ADDRESS switch is not used by
any other device on the network. If the address is used by another device, use
the switch to select a new address. The Preselector will use the new address
when it is turned on.
5. To make sure that your GPIB network will operate reliably, verify that:
HEach device on the network has a unique device address.
HThe network has fewer than 16 devices.
HNo more than 2 meters (6 feet) of cable separates any two devices, and
that the entire network uses less than 20 meters (65 feet) of GPIB cable.
HAt least two-thirds of the devices on the network are turned on when the
network is operating.
HThe network uses a star or linear configuration, not a loop or parallel
configuration.
6. Turn on the Preselector. The front-panel LEDs will light sequentially. When
the BYPASS LED lights, the unit is ready to use.
NOTE. If the LEDs do not light, refer to Chapter 3, Performance Verification.
Pressing the REMOTE/LOCAL switch will not turn on remote operation; it only
turns remote operation off.
7. Turn on the spectrum analyzer.
8. Turn on the controller and start the GPIB communications software.
9. Connect the RF source to the RF INPUT connector on the Preselector’s front
panel.

Using the Preselector
2706 RF Preselector 2–3
The Preselector is now ready for remote operation. You can operate it by using a
controller to send commands described in the following GPIB Common and
Device Commands section.
Refer to Appendix B, Using the GPIB Interface, and your controller’s operating
manual for detailed information about sending GPIB commands.
GPIB Common and Device Commands
This section briefly lists the common and device commands used to operate the
Preselector from a remote GPIB controller. Appendix B, Using the GPIB
Interface, contains a detailed, alphabetical listing of these commands and
provides an example program.
Common commands (preceded by an asterisk in Table 2.1) are used by all
devices that meet IEEE Std. 488.2-1987. Device commands (listed without an
asterisk in Table 2.1) are specific to the Preselector and are defined only in this
manual. The Preselector has two device commands: Band STS?.
NOTE. You do not need to use timing commands such as *WAI, *OPC, and
*OPC? with the Preselector. For example, the *WAI command normally prevents
a GPIB device from executing commands until all pending operations finish.
Because the Preselector executes commands sequentially, the *WAI command
always continues immediately.
Table 2–1: Commands Supported by the Preselector
Name Full Command Title
B<NR1> Select band filter (NR1 stands for an integer from 0 to 8)
*CLS ClearStatus
*ESE and *ESE? StandardEventStatusEnable
*ESR? StandardEventStatusRegisterQuery
*IDN? IdentificationQuery
*IST? IndividualStatusQuery
*OPC and *OPC? OperationComplete
*PRE and *PRE? ParallelPollRegisterEnable
*RST Reset
*SRE and *SRE? ServiceRequestEnable
*STB? ReadStatusByte
STS? StatusSelectedBandQuery

Using the Preselector
2–42706 RF Preselector
Table 2–1: Commands Supported by the Preselector (Cont.)
Name Full Command Title
*TST? Self-Test
*WAI Wait To Continue