Agilent 7A_252C 48A_252C 49A Operation & Programming Datasheet

Page 1

Operating and Programming Guide

This guide describes how to use and program the Agilent 53147A, 53148A, and 53149A. The information in this guide applies to instruments having the number prefix listed below, unless accompanied by a “Manual Updating Changes” package indicating otherwise.

SERIAL PREFIX NUMBER: US4047 (53147A)

US4048 (53148A) US4049 (53149A)

Agilent 53147A/148A/149A Microwave Frequency Counter/ Power Meter/DVM

Page 2

 Copyright Agilent Technologies, Inc. 2001, 2002

Printed: May 2002

Printed in U.S.A.

Manual part number 53147-90009

Certification and Warranty

Certification

Agilent Technologies, Inc. certifies that this product met its published specification at the time of shipment from the factory. Agilent further certifies that its calibration measurements are traceable to the United States National Institute of Standards and Technology (formerly National Bureau of Standards), to the extent allowed by the Institute’s calibration facility, and to the calibration facilities of other International Standards Organization members.

Warranty

Agilent warrants Agilent hardware, accessories and supplies against defects in materials and workmanship for a period of one year from date of shipment. If Agilent receives notice of such defects during the warranty period, Agilent will, at its option, either repair or replace products which prove to be defective. Replacement products may be either new or like-new.

Agilent warrants that Agilent software will not fail to execute its programming instructions, for the period specified above, due to defects in material and workmanship when properly installed and used. If Agilent receives notice of such defects during the warranty period, Agilent will replace software media which does not execute its programming instructions due to such defects.

For detailed warranty information, see back matter.

Safety Considerations

General

This product and related documentation must be reviewed for familiarization with this safety markings and instructions before operation.

Before Cleaning

Disconnect the product from operating power before cleaning.

Warning Symbols That May Be Used In This Book

Instruction manual symbol; the product will be marked with this symbol when it is necessary for the user to refer to the instruction manual.

Indicates hazardous voltages.

Indicates earth (ground) terminal.

Indicates terminal is connected to chassis when such connection is not apparent.

Indicates Alternating current.

Indicates Direct current.

Safety Considerations (cont’d)

WARNING

BODILY INJURY OR DEATH MAY RESULT FROM FAILURE TO HEED A WARNING. DO NOT PROCEED BEYOND A WARNING UNTIL THE INDICATED CONDITIONS ARE FULLY UNDERSTOOD AND MET.

CAUTION

Damage to equipment, or incorrect measurement data, may result from failure to heed a caution. Do not proceed beyond a CAUTION until the indicated conditions are fully understood and met.

Safety Earth Ground

An uninterruptible safety earth ground must be maintained from the mains power source to the product’s ground circuitry.

WARNING

WHEN MEASURING POWER LINE SIGNALS, BE EXTREMELY CAREFUL AND ALWAYS USE A STEP-DOWN ISOLATION TRANSFORMER WHICH OUTPUT IS COMPATIBLE WITH THE INPUT MEASUREMENT CAPABILITIES OF THIS PRODUCT. THIS PRODUCT’S FRONT AND REAR PANELS ARE TYPICALLY AT EARTH GROUND. THUS, NEVER TRY

TO MEASURE AC POWER LINE SIGNALS WITHOUT AN ISOLATION TRANSFORMER.

For additional safety and acoustic noise information, see back matter.

Agilent Technologies, Inc. 7.C.NL.10.31.00.R1.M.CW6FC 5301 Stevens Creek Boulevard Santa Clara, California 95052-8059

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Contents

Contents and Organization xii Related Documents xiii Types of Service Available if Instrument Fails xiv Repackaging for Shipment xv Product Description xvi Options xvii Accessories Supplied and Available xviii Agilent 53147A/148A/149A Quick Reference Guide xix

1 Getting Started

The Front Panel at a Glance 1-2 The Front Panel Indicators at a Glance 1-3 The Front Panel Menus at a Glance 1-5 The Display Annunciators at a Glance 1-6 The Display Special Characters at a Glance 1-7 The Rear Panel at a Glance 1-8 Operating the Instrument 1-9

Turning the Instrument On 1-11 Turning the Display Backlight Off or On 1-12 Using the Menu 1-13

Displaying the Menu 1-13 Navigating in the Menu and Changing Settings 1-13 Setting the Serial Port Baud Rate (Menu Example) 1-16

Selecting the Counter Input Channel 1-17 Measuring Frequency 1-18 Measuring Relative Frequency 1-20 Offsetting a Frequency Measurement 1-21 Measuring Power 1-23

Selecting a Power Meter Head (Sensor) Model 1-23

Measuring Power 1-25 Selecting the Unit of Measurement for Power 1-26 Measuring Relative Power 1-27

Offsetting a Power Measurement 1-27

Operating and Programming Guide iii

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Contents

Setting the Measurement Rate 1-29 Setting the Number of Averages 1-30 Setting the Resolution for Frequency Measurements 1-31 Measuring Voltage 1-33

2 Operating Your Instrument

Introduction 2-2

Chapter Summary 2-2 How this Instrument Works for You 2-3 Summary of the Measurement Sequence 2-4 Using the Selection Keys 2-5

Sequencing Through the Menu 2-5

Numeric Entry 2-6

Changing States 2-6 Using the Clear and Reset/Local Keys 2-8

Acknowledging Messages 2-8 Other Function Selection Keys 2-9 Measuring Frequency 2-11 Setting the Resolution and Measurement Rate 2-13

Setting the Resolution 2-13

Resolution Setting Example 2-14

Setting the Measurement Rate 2-15

Rate Setting Example 2-15

Setting the Number of Averages 2-16

Averages Setting Example 2-16 Measuring Relative Frequency 2-19

Relative Frequency Example 2-19 Offsetting a Frequency Measurement 2-20

Frequency Offset Example 2-20 Measuring Power 2-23

Selecting a Power Head (Sensor) 2-23

Making a Power Measurement 2-23

Power Measurement Example 2-24

Modifying and Adding Calibration Factor Tables 2-27

Calibration Table Modification Example 2-28

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Contents

Measuring Relative Power 2-38

Relative Power Example 2-38

Offsetting a Power Measurement 2-39

Power Offset Example 2-39

Measuring Voltage 2-42

Voltage Measurement Example 2-42

Using the Menu 2-43

Navigating in the Menu and Changing Settings 2-45 Reference Oscillator (REF OSC) 2-46 Power Reference (PWR REF) 2-47 Save User Settings (SAVE) 2-47 Recall User Settings (RECALL) 2-47 Channel 1 Low-Pass Filter (CH1 LPF) 2-47 Frequency Modulation (FM) 2-48 RS-232 Serial Port Data Rate (BAUD) 2-48 Preset 2-48 Model Number, Firmware Version, Serial Number,

and Option Codes 2-49 Operating Hours (OP HOURS) 2-49 Battery Voltage (BATT VOLTAGE) 2-50 Do Self Test 2-50 Power Head Selection (HEAD) 2-50 GPIB Address (GPIB ADDR) 2-50

3 Programming

Introduction 3-2 Chapter Summary 3-3 How to Use This Chapter 3-5

New Users 3-5

What You Should Understand 3-5 Learning to Program the Instrument 3-6

Experienced Programmers 3-6

Applications 3-7 Assumptions 3-8 Related Documentation 3-9 Front Panel to SCPI Command Map 3-11

Operating and Programming Guide v

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Contents

Command Summary 3-16

SCPI Conformance Information 3-16 IEEE 488.2 Common Commands 3-17 Agilent 53147A/148A/149A SCPI Subsystem Commands 3-20 Std/New Column 3-20

Parameter Form Column 3-20 *RST Response 3-28 Programming the Instrument for Remote Operation 3-30 Connecting the Instrument to a Computer 3-31

Connecting With the GPIB 3-31

Configuring the GPIB 3-31

Changing the GPIB Address 3-32 IEEE 488.1 Interface Capabilities 3-32 Connecting With the RS-232 Serial Interface 3-33

Making an RS-232 Cable 3-33

Assembling the DB-25/RJ12 Adapter and the Cable 3-34

Connecting with the Serial Interface 3-37

Remote/Local Operation 3-37

Overview of Command Types and Formats 3-38

Common Command Format 3-38 SCPI Command and Query Format 3-38

Elements of SCPI Commands 3-39

Subsystem Command Syntax 3-39 Common Command Syntax 3-39 Abbreviated Commands 3-40 Keyword Separator 3-40 Optional Keyword 3-40 Parameter Types 3-41 Parameter Separator 3-43 Query Parameters 3-43 Suffixes 3-43

Suffix Elements 3-43

Suffix Multipliers 3-44

Command Terminator 3-44

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Contents

Using Multiple Commands 3-45

Program Messages 3-45 Program Message Syntax 3-45

Overview of Response Message Formats 3-47

Response Messages 3-47 Response Message Syntax 3-47 Response Message Data Types 3-49

Status Reporting 3-51

Status Byte Register and

Service Request Enable Register 3-53 Status Byte Register 3-53 Service Request Enable Register 3-55

Standard Event Status Register Group 3-56

Standard Event Status Register 3-56

Standard Event Status Enable Register 3-58

The Operation and Questionable Data Status Register Groups 3-59

Condition Register 3-60 Transition Filter 3-60 Event Register 3-61 Event Enable Register 3-62 Operation Status Register Group 3-63 Questionable Data Status Register Group 3-65

Programming the Instrument

for Status Reporting 3-67

Determining the Condition of the Instrument 3-67 Resetting the Instrument and Clearing

the Remote Interface—Example 1 3-68

Using the Standard Event Status Register to

Trap an Incorrect Command—Example 2 3-68

Event Status Register 3-68

Using the Operation Status Register to Alert the Computer When

Measuring is Complete—Example 3 3-69

Operation Status Register 3-69

Programming the Instrument to Display Results 3-72

Configuring the Instrument's Display 3-72

Operating and Programming Guide vii

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Contents

Commands for Displaying Results 3-73

Command for Displaying Raw Results 3-73 Commands for Displaying Relative Results 3-73 Commands for Enabling and Disabling the Display 3-73

Programming the Instrument to

Synchronize Measurements 3-74

Synchronizing Measurement Completion 3-74 Resetting the Instrument and Clearing the Interface 3-74 Using the *WAI Command 3-75 Using the *OPC? Command 3-76 Using the *OPC Command to Assert SRQ 3-76

Writing SCPI Programs 3-78 Programming Examples 3-80

Using BASIC 3-80

Sending Double-Quoted and Single-Quoted Strings 3-80 Using C 3-81 List of the Programming Examples 3-81

Making a Frequency Measurement (BASIC) 3-82 Making a Frequency Measurement (QuickBASIC) 3-83 Making a Frequency Measurement (C) 3-84

Command Reference 3-86 :ABORt Command 3-88 :CALibration Subsystem 3-89 :DISPlay Subsystem 3-95 Group Execute Trigger (GET) 3-97 :INITiate Subsystem 3-98 :INPut Subsystem 3-99 :MEASure Subsystem 3-100

Measurement Instructions

(:CONFigure, :FETCh, :MEASure, :READ) 3-100 Descriptions of the Measurement Functions 3-106 How to Use the Measurement Instruction Commands 3-109

Using :MEAsure 3-109 Using :CONFigure with :READ? 3-110

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Contents

:MEMory Subsystem 3-111 [:SENSe] Subsystem 3-113 [:SENSe]:FUNCtion Subtree 3-118

[:SENSe]:POWer Subtree 3-120 [:SENSe]:ROSCillator Subtree 3-121

:STATus Subsystem 3-122

:STATus:OPERation Subtree 3-122 :STATus:QUEStionable Subtree 3-127

:SYSTem Subsystem 3-130

:SYSTem:COMMunicate Subtree 3-130 :TRIGger Subsystem 3-133 :UNIT Subsystem 3-134 Common Commands 3-135

*CLS (Clear Status Command) 3-135

*DDT <arbitrary block>

(Define Device Trigger Command) *DDT? (Define Device Trigger Query) 3-136

*ESE (Standard Event Status Enable Command)

*ESE? (Standard Event Status Enable Query) 3-137 *ESR? (Event Status Register Query) 3-139 *IDN? (Identification Query) 3-140 *IST? (Instrument Status) 3-140 *OPC (Operation Complete Command) 3-141 *OPC? (Operation Complete Query) 3-141 *PRE (Parallel Poll Enable Register)

*PRE? (Parallel Poll Enable Register Query) 3-142 *RCL (Recall Command) 3-142 *RST (Reset Command) 3-143 *SAV (Save Command) 3-144 *SRE (Service Request Enable Command)

*SRE? (Service Request Enable Query) 3-145 *TRG

(Trigger Command) 3-147 *TST? (Self-Test Query) 3-148 *WAI (Wait-to-Continue Command) 3-149

Operating and Programming Guide ix

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Contents

Errors 3-150

Reading an Error 3-150 Error Queue 3-151 Error Types 3-152 No Error 3-152 Command Error 3-152 Execution Error 3-153 Device-Specific or Instrument-Specific Error 3-153 Query Error 3-154 Error List 3-154

4 Specifications

Introduction 4-2

Measurement Specifications and Characteristics 4-3

A Rack Mounting the Instrument

Rack Mounting the Instrument A-2

B Messages

Overview B-2 Status Messages B-2 Self-Test Messages B-3 Error Messages B-4

C Using the Battery Option

Overview C-2 Operating the Instrument from the Batteries C-2 Operating the Instrument

from a DC Power Source C-4

Replacing the Batteries C-5

Removing the Batteries C-5

Installing Batteries C-5 Charging the Batteries C-8 Precautions C-9

Index

x Operating and Programming Guide

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In This Guide

This book is the Operating and Programming Guide for the Agilent 53147A, 53148A, and 53149A. It consists of a table of contents, this preface, a quick-reference guide, four chapters, three appendices, and an index.

This preface contains the following information:

• Contents and Organization pg. xii

• Related Documents pg. xiii

• Types of Service Available if Instrument Fails pg. xiv

• Repackaging for Shipment pg. xv

• Product Description pg. xvi

• Options pg. xvii

• Accessories Supplied and Available pg. xviii

• Manuals Supplied pg. xviii

Operating and Programming Guide xi

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In This Guide

Contents and Organization

The Quick Reference Guide consists of a Menu Tree (tear-out sheet) that serves as a tool to trigger your memory or get you quickly reacquainted with the instrument.

Chapter 1 Getting Started is a quick-start guide that gives you a brief overview of the instrument’s keys, indicators, menus, display, and connectors. A graphical procedure for performing a measurement is also provided.

Chapter 2 Operating Your Instrument is an operator’s reference. You are given an overview of each group of front-panel keys, operating functions, and menus followed by a series of exercises that guide you through the operation of the instrument.

Chapter 3 Programming provides information that you can use to remotely operate the instrument.

Chapter 4 Specifications lists the specifications and characteristics of the instrument.

Appendix A Rack Mounting the Instrument provides rack-mounting procedures for the instrument.

Appendix B Messages lists and explains all of the messages that are displayed on the instrument’s front panel and/or sent over the RS-232 serial interface.

Appendix C Using the Battery Option explains how to use the instrument with the Battery option.

Index

xii Operating and Programming Guide

Page 13

In This Guide

Types of Service Available if Instrument Fails

If your instrument fails within one year of original purchase, Agilent will repair it free of charge. If your instrument fails after your one-year warranty expires, Agilent will repair it, or you can repair it yourself.

There are three types of repair services:

• Standard repair service—if downtime is not critical.

• Express Repair/Performance Calibration Service—if downtime is

critical.

• Owner repair—repair the unit yourself using the Assembly-Level Service Guide.

Standard Repair Services (Worldwide)

Contact your nearest Agilent Service Center to arrange to have your instrument repaired.

Express Repair/Performance Calibration Service (USA Only)

If downtime is critical, you can receive your repaired instrument via overnight shipment. Just call 1-800-403-0801 and ask for Express Repair/Performance Calibration Service. When your instrument is repaired, it will be returned via overnight shipment.

Repair Instrument Yourself

If you choose to repair the instrument yourself or would like more details on self test and calibration, use the procedures in the Assembly-Level Service Guide.

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In This Guide

Repackaging for Shipment

For the Express Repair/Performance Calibration Service described above, return your failed instrument to the designated Agilent Service Center, using the instrument’s original shipping carton (if available). Agilent notifies you when your failed instrument is received.

If the instrument is to be shipped to Agilent for service or repair, be sure you do the following:

• Attach a tag to the instrument identifying the owner and indicating the required service or repair. Include the instrument model number and full serial number.

• Place the instrument in its original container (if available) with appropriate packaging material.

• Secure the container with strong tape or shipping bands.

If the original shipping container is not available, place your unit in a container with at least 4 inches of compressible packaging material around all sides of the unit. Use static free packaging materials to avoid additional damage to your unit.

Agilent suggests that you always insure shipments.

Operating and Programming Guide xv

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In This Guide

Description of the Microwave Frequency Counter/Power Meter/DVM

The Agilent 53147A, 53148A, and 53149A are capable of measuring frequencies from 10 Hz to 125 MHz on Channel 1 and from 50 MHz to 20 GHz (53147A), 26.5 GHz (53148A), and 46 GHz (53149A) on Channel 2. These instruments are also capable of measuring power (the power and frequency ranges for power measurement are dependent on the powersensor model used) and DC voltages up to ±50 VDC. All three instruments have a maximum frequency resolution of 1 Hz.

The Agilent 53147A/148A/149A provide GPIB and RS-232 serial interfaces and are suitable for field, bench-top, and ATE operation.

The basic measurement functions of the Agilent 53147A/148A/149A includes Frequency, Relative Frequency, Frequency Offset, Power, Power Offset, Relative Power, and DC voltages. All of these features are accessible from the front panel and over the GPIB and RS-232 interfaces.

The Agilent 53147A/148A/149A includes the following additional measurement functions and features that are designed specifically for manufacturing and service applications:

• 1, 2, 5, and 10 MHz external reference capability

• Optional high-stability oven oscillator for high-accuracy needs and

lengthened calibration cycles

• Frequency and power offset capabilities for relative measurements

• SCPI programming capability

• Battery and dc input option for operation in locations where AC

power is unavailable

• Optional soft carrying case for safe transportation and mobile use

Programmable control is performed via a GPIB or an RS-232 serial interface. The GPIB and RS-232 ports are standard for the Agilent 53147A, 53148A, and 53149A.

xvi Operating and Programming Guide

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In This Guide

Options

The options available for the Agilent 53147A/148A/149A are listed below. Specifications for the options are listed in Chapter 3, “Programming.” Options ordered with the instrument are installed at the factory and are ready for operation on delivery. Refer to the “Retrofitting Options” chapter in the Agilent 53147A/148A/149A Assembly-Level Service Guide for information on installing options in the field.

Hardware

• High Stability Oven Timebase, Option 001

• Battery/DC Power Input, Option 002

• Rack Mount Kit, Option 1CM

• Soft Carrying Case, Option 007

Retrofit

Options 001 and 002 can be installed only by authorized Agilent Technologies Repair Centers.

Operating and Programming Guide xvii

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In This Guide

Accessories Supplied and Available

Accessories Supplied

• Power cord, 2.3 meters (Part number dependent upon destination country)

• Power sensor cable (Agilent 11730A)

• DVM test leads (Agilent 34132B)

Accessories Available

• Soft Carrying Case (Agilent P/N 53147-80016)

• Automotive Power Adapter (Agilent P/N 53150-60214)

• Battery (Agilent P/N 53150-80010)

• GPIB Cables (Agilent 10833A/B/C/D)

• RS-232 Cable (Agilent P/N 53150-60215)

• Power Sensors (Agilent 8480 series)

Manuals Supplied

Agilent 53147A/148A/149A Operating and Programming Guide (Agilent P/N 53147-90009)

Agilent 53147A/148A/149A Assembly-Level Service Guide

(Agilent P/N 53147-90010)

xviii Operating and Programming Guide

Page 19

Agilent 53147A/148A/149A Quick Reference Guide

The Quick Reference Guide is designed for experienced users of the Agilent 53147A, 53148A, and 53149A. It is intended to be used as a tool to trigger your memory. If you are using the instrument for the first time, it is recommended that you at least read Chapter 1, “Getting Started,” first.

The Quick Reference Guide, which follows this page, consists of a menu tree that may be torn out of the guide for external use.

Reference

Quick

xix

Page 20

Quick

Reference

Page 21

Agilent 53147A/148A/149A Frequency Counter/Power Meter/DVM

GHz MHz kHz Hz

Reset/ Local

REF OSC > INT

REF OSC > EXT

PWR REF > OFF

PWR REF > ON

SAVE > 0 to 9

RECALL > 0 to 9

CH1 LPF > OFF

CH1 LPF > ON

FM > AUTO

FM > OFF

BAUD > 9600

BAUD > 4800

BAUD > 2400

BAUD > 1200

BAUD > 19200

BAUD > 14400

PRESET

53147A >

< 2060162-00 >

OP 9999 HRS

BATT VOLTAGE

0.0

DO SELF TEST

HEAD > OFF

HEAD > 8487A

HEAD > 8485A

HEAD > 8482A

HEAD > 8481D

HEAD > 8481A

CUSTOMHEAD >1

CUSTOMHEAD >2

CUSTOMHEAD >3

GPIB ADDR > 0 to 30

< US 000 001 11 >

GHz MHz kHz Hz

Freq Offset

Resol

00 000 000 000 000

49 999 999 999 999

GHz MHz kHz Hz

Freq Offset

Resol

RESOL 1 HZ

RESOL 10 KHZ

RESOL 100 KHZ

RESOL 1 MHZ

* *.* = Counter frequency

GHz MHz kHz Hz

Cal Factor

Freq

150.0

050.0

GHz MHz kHz Hz

Cal Factor

Freq

* *.*

00.0

max.

GHz MHz kHz Hz

Rate

+ / –

GHz MHz kHz Hz

Pwr Offset

Avg

± 00.00

± 99.99

GHz MHz kHz Hz

Pwr

Offset

Avg

AVERAGES 01

AVERAGES 99

Reference

Quick

RATE FAST

RATE MED

RATE SLOW

RATE HOLD

QR-1

Page 22

Quick

Reference

QR-2

Page 23

Getting Started

Page 24

Chapter 1 Getting Started

The Front Panel at a Glance

1951820

COUNTER

Offset On/Off

6 7 8

20 GHz Counter/Power Meter/DVM

Ext Rel Rate Rmt SRQ

Error Shift

POWER METER

dBm/W

Display Power

Rel Pwr

Offset On/Off

Rel FreqChan

Hold

Pwr Ref

Zero

Store

Cal

Display DVM

141517

Counter

Power Meter

DVM

DAMAGE

DVM

±60 VDC

12 91011

–

POWER METER

OUTPUT

Power Ref.

1.00mW 50MHz

INPUT

Do NOT Exceed Sensor Max Power

COUNTER

CHANNEL 1

10 Hz to 125 MHz

1MΩ

DAMAGE

+30 dBm

COUNTER

CHANNEL 2

50MHz to 20 GHz

DAMAGE

+27 dBm

50Ω

15 Calibrate / Store key 16 Relative Frequency key 17 Power Offset On/Off / Relative Power key 18 Frequency Offset On/Off key 19 Selection (arrow) keys 20 Counter Channel Selection key 21 Gate indicator 22 Enter key 23 Frequency / Calibration Factor key 24 Sign change (+/–) / Rate key 25 Resolution / Frequency Offset key 26 Clear / Display Backlight On/Off key 27 Reset/Local / Menu key 28 Shift key 29 Standby indicator

POWER

Standby

Reset/ Local

Shift

Ch 12

Rel Freq

Offset

Avg On

Rel Pwr

Offset

Freq Offset

Resol

On/Off

Clear

Cal Factor

Freq

Rate

+ / -

GHz

MODIFY

Pwr Offset

Avg

Enter

2122232425262728

MHz kHz

dB dBm Watts mW uW

Gate

Select

1 Power / Standby switch 2 Average / Power Offset key 3 LCD display 4 Selection-keys-active indicator 5 Display Power / dBm/W key 6 Instrument-function indicators

(Counter / Power Meter / DVM)

7 Power Reference Output connector 8 Channel 1 input connector

Channel 2 input connector

10 Power Meter Input connector 11 DVM + connector 12 DVM – connector 13 Zero key 14 Display DVM key

1-2 Operating and Programming Guide

Page 25

Chapter 1 Getting Started

The Front Panel Indicators at a Glance

There are five front-panel LED indicators. These are listed and described in the following table.

Indicator Description

The Standby indicator is lit whenever the power cord is connected (or the battery option is supplying power), and the POWER switch on the front panel is

POWER

Standby

OFF (out). During Standby, most of the instrument’s circuits do not receive power. The cooling fan and the timebase are powered to maintain temperature stability in the timebase components, and if the Battery option is installed, the battery-charging circuits are powered. When you press the POWER switch on the front panel, the Standby indicator goes off, and all of the instrument’s circuits receive power.

The function LEDs light to indicate which of the instrument’s functions are displayed. If frequency is the only measurement displayed (the Power Meter and the DVM are disabled), only the Counter LED is

Counter

Power Meter

DVM

lit. If both frequency and power measurements are displayed (the Counter and the Power Meter are enabled), the Counter and Power Meter LEDs are lit. If a voltage reading and a power reading are displayed (the DVM and the Power Meter are enabled), the Power Meter and DVM LEDs are lit. If only a voltage reading is displayed (the DVM is the only function enabled), the DVM LED is lit, and the Counter and Power Meter LEDs are not lit.

When the LED indicator between the arrow keys flashes, the arrow keys can be used to navigate and change values in menus.

When you make a change in a menu, always press the Enter key to save the setting and exit the menu.

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Chapter 1 Getting Started

COUNT

Gate

Chan Select

The Front Panel Indicators at a Glance

Indicator Description

The Gate LED indicator flashes to indicate the rate at which Counter measurements are triggered. The flash rate of the LED varies with the settings of the measurement rate (Rate key) and the Counter measurement resolution (Resol key). The flash rate of the LED provides a rough indication of the number of Counter measurements that are being taken in a given period of time.

NOTE It is normal for the fan to run when the instrument is in Standby mode.

Power is supplied to the timebase whenever the instrument is connected to a power source, and the fan runs to cool the power supply.

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Chapter 1 Getting Started

The Front Panel Menus at a Glance

Shift

Reset/ Local

REF OSC > INT

REF OSC > EXT

PWR REF > OFF

PWR REF > ON

SAVE > 0 to 9

OP 9999 HRS

BATT VOLTAGE

0.0

RECALL > 0 to 9

CH1 LPF > OFF

CH1 LPF > ON

FM > AUTO

FM > OFF

DO SELF TEST

HEAD > OFF

HEAD > 8487A

HEAD > 8485A

HEAD > 8482A

BAUD > 9600

BAUD > 4800

HEAD > 8481D

HEAD > 8481A

BAUD > 2400

BAUD > 1200

BAUD > 19200

BAUD > 14400

GPIB ADDR > 0 to 30

PRESET

53147A >

< 2060162-00 >

RATE FAST

RATE MED

RATE SLOW

RATE HOLD

CUSTOMHEAD >1

CUSTOMHEAD >2

CUSTOMHEAD >3

Rate

+ / –

< US 400 001 11 >

Freq Offset

Resol

RESOL 1 HZ

RESOL 10 KHZ

RESOL 100 KHZ

RESOL 1 MHZ

Operating and Programming Guide 1-5

Page 28

Chapter 1 Getting Started

The Display Annunciators at a Glance

GHz

MHz

kHz

Ch 12

Rel Freq

Offset

Avg On

Rel Pwr

Offset

Annunciator

Ch 1 or Ch 2

Freq

Rel Freq

Freq

Description

Indicates which channel is selected to measure an input signal.

Indicates that the value displayed is a frequency reading.

The displayed frequency value is relative to a previously stored value.

The displayed frequency value is offset by a previously entered frequency value.

dB dBm Watts mW uW %

Offset

Avg On

The displayed measurement value is the result of a number of individual measurements that have been averaged.

Pwr

Rel Pwr

Pwr Offset

dB, dBm, Watts, mW,

µW, nW, %

The instrument is set to measure Power (Power Meter is on).

The displayed power measurement is relative to a previously stored power value.

The displayed power value is offset by a previously entered power value.

Indicates the unit of measurement for the currently displayed power value.

Provides a real-time analog representation of the Power measurement (intended for peaking and similar procedures).

Ext Ref

Hold

Rmt, SRQ

The Counter is using an external reference Timebase for frequency measurements.

Indicates the instrument is in Hold (single-measurement) mode.

Shows the current state of the GPIB interface (Rmt = Remote operation via GPIB; SRQ = Service ReQuest).

Error

Shift

Pwr Ref

Indicates that a front-panel key command is unacceptable in the current context.

Indicates that all front-panel keys are redefined to the function printed above the key.

Indicates that the 1 mW power reference output is turned on.

Shows the amount of charge in the batteries (if the Battery option is installed).

Ext Ref

Hold

Rate Rmt SRQ

Error

Pwr Ref

Shift

1-6 Operating and Programming Guide

Page 29

Chapter 1 Getting Started

The Display Special Characters at a Glance

Special

Characters

Points to the current value for a Menu setting.

Indicates that the value for the current Menu setting can be changed using the selection (arrow) keys.

NOTE The special characters shown above are intended to help you navigate

within the Menu. When the right pointer ( ) is flashing, it indicates the current setting for the selected Menu option. When the left pointer ( ) is flashing, it indicates that you can use the selection (arrow) keys to change the setting for the current Menu option. To switch between the two, press the right arrow key when the right pointer ( ) is flashing, or press the left arrow key when the left pointer ( ) is flashing.

Description

Operating and Programming Guide 1-7

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Chapter 1 Getting Started

The Rear Panel at a Glance

Counter/ Power Meter/ DVM

Standard

Main Power

AC POWER 90-130 VAC 50/60/400 Hz 190-230 VAC 50/60 Hz

RS-

232

In or Out

OPTIONS

001 Oven Time Base 002 Battery

GPIB

Auxiliary

Agilent

Reference 10 MHz

FUSE

1.0A 250V

Made in U.S.A.

of domestic and foreign content

Counter/ Power Meter/ DVM

Made in U.S.A.

of domestic and foreign content

Battery

Battery Charging

EXT DC

11 to 18 VDC

With Battery Option

WARNING:

AC POWER 90-130 VAC 50/60/400 Hz 190-230 VAC 50/60 Hz

WARNING:

To avoid electrical shock: Do not remove covers.

Main Power

RS-

232

To avoid electrical shock: Do not remove covers.

No user serviceable parts inside. Refer all servicing to qualified personnel.

Reference 10 MHz

In or Out

FUSE

1.0A 250V

No user serviceable parts inside. Refer all servicing to qualified personnel.

OPTIONS

001 Oven Time Base 002 Battery

GPIB

Auxiliary

This unit must be earth grounded.

Agilent

Made in U.S.A.

BATTERY PACK

of domestic and foreign content

1 AC Input/Power module (Senses

incoming voltage and adjusts automatically)

2 Fuse Holder (behind door) 3 External Reference connector (BNC)

1, 2, 5, 10 MHz Input, 10 MHz Output

4 Auxiliary connector (reserved) * 5 Battery option cover plate

6 GPIB Interface connector (IEEE-488.2) 7 RS-232 Interface connector (RJ12) 8 Serial number plate

9 Battery sled (Battery option only) 10 Battery power switch (Battery option only) 11 Battery Charging LED (Battery option only) 12 EXT DC power-input connector (Battery option only)

* The Auxiliary connector is not installed on standard production units.

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Operating the Instrument

The procedures in this section are designed to familiarize you with the instrument’s features and controls. Agilent suggests that you follow the steps for each of these procedures, even if you do not presently need to make any measurements or to adjust any of the instrument’s settings. The following procedures are provided:

• Turning the Instrument On

• Turning the Display Backlight Off or On

• Selecting an Input Channel

• Using the Menu

• Setting the Serial Port Baud Rate

• Measuring Frequency

• Measuring Relative Frequency

• Offsetting a Frequency Measurement

• Setting the Power Head Model Number

• Measuring Power

• Measuring Relative Power

• Offsetting a Power Measurement

• Setting the Measurement Rate

• Setting the Number of Averages

• Setting the Resolution

• Measuring Voltage

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The following legend defines the meanings of the icons used throughout this chapter.

Legend

1 Press key one

time and release

2 Multiple key

presses

3 Result 4 Auto operation 5 Connect signal 6 Disconnect signal

798

7 Indicator off 8 Indicator on 9 Indicator flashing

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Turning the Instrument On

To turn on the instrument, press and release the POWER button on the front panel.

POWER

Standby

Ch 12

Rel Freq

Offset

Avg On

Rel Pwr

Offset

Ext Ref

dB dBm Watts mW uW %

Hold

Rate Rmt SRQ

Pwr Ref

Error Shift

Ch 2

Freq

NOTE If a signal was applied to the Counter’s Channel 2 input connector prior

to turning on the instrument, CH2 NO SIGNAL is displayed momentarily. As soon as the Counter acquires the input signal, it displays the signal’s value.

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NOTE The internal Reference Oscillator requires 15 minutes to reach a stable

operating temperature. Since the Reference Oscillator receives power only when the instrument is on or in Standby mode, no measurements should be taken unless the instrument has been receiving power for at least that amount of time.

Turning the Display Backlight Off or On

When you first turn the instrument on, the backlight for the LCD display is always lit. You can toggle the backlight off and on by pressing the Shift key and then the On/Off (Clear) key, as shown below.

Shift

Ch 2

Freq

Shift

On/Off

Clear

Shift

On/Off

Clear

Ch 2

Freq

Ch 2

Freq

Ch 2

Freq

Shift

NOTE If your instrument has the Battery option, you can extend the length of

time the instrument can operate from the batteries by turning off the display backlight.

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Operating the Instrument

Using the Menu

The Agilent 53147A/148A/149A has one menu that you use to control a number of the instrument’s features and functions.

Displaying the Menu

To display the Menu, press the Shift key and then the Menu (Reset/Local) key, as shown below.

Ch 2

Shift

Reset/ Local

Freq

Shift

Navigating in the Menu and Changing Settings

Use the Selection (arrow) keys to navigate to the setting you want to change and then to actually make the changes. For example, the diagram on the next page shows how to change the setting of the Reference Oscillator from INTernal to EXTernal. (In this example, a reference signal is applied to the External Reference connector, but no signal is applied to the Channel 2 input.)

NOTE The instrument does not switch to EXTernal unless a suitable reference

signal is available at the External Reference connector.

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Ch 2

Shift

Reset/ Local

Freq

Shift

Enter

Ch 2

Ext Ref

When you select the Menu, the indicator between the arrow keys flashes to indicate that the arrow keys are now active. Since the Reference Oscillator setting is the first one displayed when you invoke the Menu (unless you’ve used the Menu to change another setting since you turned the instrument on), you don’t have to use the (up-arrow) key or the

(down-arrow) key to get to it.

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When you press the (right-arrow) key, the flashing annunciator ( ) changes direction, and the current setting for the Reference Oscillator (INT [internal] or EXT [external]) flashes. This indicates that you can now change this setting. Use either the up-arrow key or the down-arrow key to change the setting.

If there are more than two settings available for the currently selected function, you can cycle through the available settings by repeatedly pressing either the up-arrow key or the down-arrow key. For example, to change the setting for the Baud rate for the serial port, use the sequence on the next page.

Press either the Enter key or the left arrow key to accept the currently displayed setting. The Enter key accepts the setting and exits the Menu; the left arrow key accepts the setting but does not exit the Menu. Use the left arrow key to accept a setting if you want to change additional menu settings. The Clear key reverses an unaccepted setting change.

You navigate to and adjust the remaining settings available in the Menu in the manner described above. The Menu also contains some items that provide information only (no settings are required [or possible] for these), such as Battery Voltage, Operation Hours, and information that identifies the instrument (Agilent model number, firmware version number, serial number, and installed option codes). These menu options and the ones described below are shown in “The Front Panel Menus at a Glance” on page 1-5.

There is also a menu item called Preset and one called Do Self Test. If you press the Enter key while PRESET is displayed, all of the instrument’s settings are returned to the factory-default settings. If you press Enter while DO SELF TEST is displayed, the instrument repeats the tests that are normally performed when the instrument is first turned on.

NOTE Remember to terminate each value you change in any of the menu options

by pressing the any menu option while the Menu is displayed by pressing the key or the

Enter key or the left arrow key. You can abort a change to

Reset/Local

Clear key. Both keys nullify any changes you made to the

current menu option, but they do not affect any changes to other menu options. The

Reset/Local key does not.

Clear key terminates the current menu session, but the

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Setting the Serial Port Baud Rate (Menu Example)

Ch 2

Shift

Reset/ Local

Freq

Shift

Ch 2

Enter

Freq

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Selecting the Counter Input Channel

You can toggle between Counter Channels 1 and 2 by pressing the Chan Select key.

Ch 1

Chan Select

Freq

Ch 2

Freq

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Measuring Frequency

The following diagram shows the basic sequence to use to make a frequency measurement using Channel 1. This example assumes that the instrument is on and has completed the Self Test. For the purposes of this example, use the 10 MHz reference output on the instrument’s rear panel as a signal source for input to Counter Channel 1.

Ch 2

Freq

COUNTER

CHANNEL 1

10 Hz to 125 MHz

DAMAGE

+30 dBm

Chan Select

Ch 2

Freq

Ch 1

Freq

Ch 1

Freq

The same procedure applies to making a basic frequency measurement on Channel 2. However, since Channel 2 is automatically selected when you turn on the instrument, the channel-selection step is unnecessary (unless you previously selected Channel 1).

CAUTION The Channel 2 input path circuits contain sensitive GaAs semiconductors.

To prevent damage to these components, always adhere to standard ESD (Electro-Static Discharge) prevention procedures, and ensure that the maximum power specification for this channel (+27 dBm) is not exceeded.

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NOTES • The Counter displays CH2 NO SIGNAL or CH1 NO SIGNAL and shuts

down all unnecessary circuits when a signal of insufficient amplitude

(or no signal) is applied to the corresponding input. This lowers the

power consumption, and if the Battery option is installed, it extends the

length of time the instrument can operate from the batteries.

• When the frequency of a signal applied to the Channel 2 input exceeds the maximum rated frequency for the Counter, it displays CH2 TOO HIGH.

• The DVM uses the same portion of the display to display voltage

measurements that the instrument uses to display frequency measurements. Therefore, the DVM and the Counter cannot display measurements simultaneously. Pressing the Display DVM key toggles the upper portion of the display between the DVM and the Counter.

CAUTION The 2.9 mm Planar Crown* connector used for the Channel 2 input on the

Agilent 53149A must be handled with care to prevent damage and/or contamination, especially since it acts as a wave guide as well as an electrical connection. Observe the following precautions when handling this connector:

1. If you remove the outer portion of the connector, do not touch the

exposed surfaces of either part of the connector with your bare skin or any material that is not intended for cleaning this type of connector.

2. Avoid dropping or striking either portion of the connector.

If the connector becomes contaminated, it can be cleaned with isopropyl alcohol and a lint-free cloth or other suitable cleaning implement.

Planar Crown® is a registered trademark of Weinschel Corp.

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Measuring Relative Frequency

You can measure the difference in frequency from one measurement to another (drift) using the Relative Frequency function. You do this by pressing the Shift and Rel Freq (Offset On/Off) keys as shown in the diagram below (this example assumes that a signal is currently applied to Channel 1).

The Counter stores the current frequency reading when you press the Rel Freq key. It then subtracts this value from all subsequent readings and displays the difference until you press the Rel Freq key again.

Shift

Rel Freq

Ch 1

Freq

Ch 1

Freq

Ch 1

Rel Freq

NOTE If the input signal fluctuates, the value displayed varies as the Counter

continues to take measurements. You can vary the speed at which measurements are taken by varying the settings for Rate and Resolution (see “Setting the Measurement Rate” and “Setting the Resolution for Frequency Measurements” on pages 1-29 and 1-31).

Shift

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Offsetting a Frequency Measurement

You can use the Frequency Offset (Freq Offset) function to add or subtract a constant value to/from a frequency measurement. For example, you can use an offset to compensate for a systematic error or to display the difference in frequency between two signals.

NOTE The Frequency Offset and Relative Frequency functions can be used

simultaneously.

To display an offset frequency measurement, you need to set the value and sign (+/–) of the offset and to turn the Frequency Offset function on. In the diagram on the next page, the Frequency Offset function is enabled first, and the offset value is then entered. However, the order doesn’t matter, so you can also enter the offset value first, and then turn the offset function on.

NOTE When you are entering a value for Frequency Offset (or Power Offset),

you can use the Reset key to restore all of the displayed digits to zero. These are the only two functions in which the Reset key has this effect.

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Ch 2

Freq

Ch 2

Offset On/Off

Shift

Freq Offset

Resol

Freq

Offset

Ch 2

Freq

Offset

Freq

Offset

Shift

Freq

Offset

Rate

+/-

Enter

Freq

Offset

Ch 2

Freq

Offset

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Operating the Instrument

Measuring Power

The Agilent 53147A/148A/149A can measure signal power (the power and frequency ranges for power measurement are dependent on the powersensor model used). To measure power, you must first set the Power Meter for the power-meter sensor (head) that you intend to use.

Selecting a Power Meter Head (Sensor) Model

The example procedure in the following diagram shows how to select the model number of the power-meter head (sensor). This procedure assumes that the Power Meter is currently set to use a model 8481A power sensor and that you intend to use a model 8482A power sensor.

NOTE When you select a power head (sensor), you are implementing a

preconfigured calibration table for that head. There are five preconfigured tables (for head models 8481A, 8481D, 8482A, 8485A, and 8487A) and three custom calibration tables (CUST 1, CUST 2, and CUST 3). You can modify the frequency/calibration-factor values in any of the data points for any power head, add data points to any configuration table (up to a maximum of 100 data points per table), and input data to build new calibration tables by selecting CUST 1, CUST 2, and/or CUST 3. Complete instructions for modifying and adding calibration tables are provided in “Modifying and Adding Calibration Factor Tables” on page 2-27.

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Ch 2

Shift

Reset/ Local

Freq

Shift

Ch 2

Enter

Freq

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Measuring Power

The procedure for measuring power that is illustrated in the following diagram assumes that the power-sensor head being used has been selected in the instrument’s menu and that the signal to be measured is connected to the head.

NOTE When the power of a signal applied to the Power Meter Input connector

exceeds the maximum rated power for the Power Meter head, the Power Meter displays HI.

Display Power

Ch 2

Freq

Pwr

Ch 2

dBm

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Selecting the Unit of Measurement for Power

The instrument’s power meter can display values in either of two sets of units of measurement—dB and dBm or Watts, mW, µW, and nW (the power meter automatically selects the most appropriate unit of measurement when Watts is selected). Use the procedure in the following diagram to select the unit of measurement for power (this procedure assumes that a signal is currently applied to the power meter and that power is being displayed):

Ch 2

Freq

Shift

Pwr

Ch 2

Freq

Pwr

dBm

Shift

dBm/W

Display Power

Ch 2

Freq

Pwr

NOTE If a signal having an amplitude that exceeds the Power Meter

specifications is applied, and power measurement is enabled, the annunciators for the power reading display “HI” to indicate that the signal’s amplitude exceeds the specification. If a signal having an amplitude below the minimum specification is applied, the power annunciators display “LO” to indicate that the signal level is too low to be measured by this Power Meter.

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Measuring Relative Power

You can measure the difference in power from one measurement to another (drift) using the Relative Power function. You do this by pressing the Shift and Rel Pwr (Offset On/Off) keys, as shown in the diagram below (this example assumes that a signal is currently applied to the Power Meter input connector).

The Power Meter stores the current power reading when you press the Rel Pwr key. It then subtracts this value from all subsequent readings and displays the difference until you press the Rel Pwr key again.

Ch 2

Shift

Rel Pwr

Offset On/Off

Freq

Pwr

Ch 2

Freq

Pwr

Ch 2

Freq

Rel Pwr

dBm

Shift

Offsetting a Power Measurement

You can use the Power Offset (Pwr Offset) function to add or subtract a constant value to/from a power measurement. For example, you can use an offset to compensate for a systematic error or to display the difference in power between two signals.

NOTE The Power Offset and Relative Power functions can be used simultaneously.

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To display an offset power measurement, you need to set the value and sign (+/–) of the offset and to turn the Power Offset function on. In the following diagram, the Power Offset function is enabled first, and the offset value is then entered. However, the order doesn’t matter, so you can also enter the offset value first, and then turn the offset function on.

Ch 2

Freq

Pwr

dBm

Rel Pwr

Offset

On/Off

Shift

Pwr Offset

Avg

+/-

Ch 2

Freq

Pwr Offset

Ch 2

Freq

Pwr Offset

Shift

Ch 2

Enter

Freq

Pwr Offset

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Setting the Measurement Rate

The measurement rate determines how frequently the instrument takes measurements (frequency, power, and/or voltage). You can set the measurement rate to FAST, MED (medium), SLOW, or HOLD (single measurement taken each time you press the Reset/Local key).

Ch 2

Freq

Shift

Rate

+/-

Enter

Ch 2

Freq

Ch 2

Freq

Hold

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Setting the Number of Averages

You can set the number of frequency, power, and/or voltage measurements the instrument takes and averages before displaying the result. The default setting is one (no averages are performed), and the maximum setting is

99. Note that the tens position (10 through 90) and the units position (0 through 9) are adjusted separately, and that you cannot set the number of averages to zero.

Ch 1

Freq

Pwr Offset

Avg

Ch 1

Enter

Freq

Avg On

Ch 1

Freq

Avg On

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NOTE For most of the instrument’s settings, when you continue to press either

However, when you adjust the value in the units position for the number of measurements to be averaged, rollover does not occur. If you press the up-arrow when the value in the tens position is zero and the value in the units position is nine, or if you press the down-arrow when the value in the tens position is zero and the value in the units position is one, there is no change. If the value in the units position could roll over (in either direction), it would allow you to set a value of zero for the number of averages. Since at least one measurement must be taken, zero is an illegal value.

NOTE When the resolution setting is high (e.g., 1 Hz), and a large number of

averages is selected, it takes a considerable amount of time for the instrument to take the measurements, compute the averages, and display a reading. As a result, the rate at which the display is updated is considerably slower than at small numbers of averages and lower resolution settings. For example, when the resolution is set to 1 Hz, and the number of averages is set to 60, a new reading is displayed every 60 seconds (approximately).

Setting the Resolution for Frequency Measurements

Since less time is required to complete each measurement as the resolution of the measurements is reduced, the resolution setting affects the rate at which measurements are taken and displayed, as well as the number of digits displayed for the measurements. As a result, the rate at which the Gate indicator flashes changes when you change the resolution.

As shown in the procedure in the diagram on the next page, the available resolution settings are 1 Hz (the default setting), 10 Hz, 100 Hz, 1 kHz, 10 kHz, 100 kHz, and 1 MHz.

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Ch 2

Freq

Freq Offset

Resol

Ch 2

Enter

Freq

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Measuring Voltage

To measure voltage, press the Display DVM key, connect the red DVM test lead to the red + DVM connector, connect the black DVM test lead to the black – DVM connector, and touch the red and black test prods to the source of the voltage you want to measure.

Ch 2

Freq

DVM

Ch 2

–

DAMAGE

±60 VDC

Display DVM

Freq

If the positive test lead is applied to a positive voltage source, and the negative lead is applied to a return for that source, the meter indicates the positive value (+) of the voltage. If the positive test lead is applied to a negative voltage source, and the negative lead is applied to a return for that source, the meter indicates the negative value (–) of the voltage.

NOTE The DVM automatically selects the appropriate voltage range to display

the measurement with maximum accuracy, and it automatically determines and displays the polarity of the voltage measured.

CAUTION The 53147A/148A/149A DVM can measure voltages up to ± 50VDC.

Applying voltages outside of the ± 60VDC range to the DVM inputs can damage the DVM.

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Operating Your Instrument

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Chapter 2 Operating Your Instrument

Introduction

This chapter contains information and usage procedures for the frontpanel keys, operating functions, and menus of the Agilent 53147A, 53148A, and 53149A.

Chapter Summary

• How this Instrument Works for You pg. 2-3

• Summary of the Measurement Sequence pg. 2-4

• Using the Selection Keys pg. 2-5

• Numeric Entry pg. 2-6

• Changing States pg. 2-6

• Acknowledging Messages pg. 2-8

• Using the Clear and Reset/Local Keys pg. 2-8

• Other Function Selection Keys pg. 2-9

• Measuring Frequency pg. 2-11

• Setting the Resolution and Measurement Rate pg. 2-13

• Setting the Number of Averages pg. 2-16

• Measuring Relative Frequency pg. 2-19

• Offsetting a Frequency Measurement pg. 2-20

• Measuring Power pg. 2-23

• Measuring Relative Power pg. 2-38

• Offsetting a Power Measurement pg. 2-39

• Measuring Voltage pg. 2-42

• Using the Menu pg. 2-43

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How this Instrument Works for You

The following is a list of some of the key things the instrument does for you.

• Presets the menus to default states and values at power-up.

• The instrument’s Menu key and other front-panel keys allow you to

select such things as the timebase source, the GPIB address, and the RS-232 serial-port baud rate. The instrument also allows you to store your selections in non-volatile memory; thus, these settings are not lost when power has been off or after a remote-interface reset.

• Automatically displays measurement(s) when you have selected a

measurement function.

• Accepts your entry for a menu item when you press the Enter key.

You must press the Enter key to complete each setting and/or selection.

• Saves user configuration settings.

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Summary of the Measurement Sequence

1. Connect the power cord to the instrument and to an appropriate power source (or, if the instrument has the Battery option, turn on the Battery Power switch), and then press and release the POWER button on the front panel.

NOTE The internal Reference Oscillator receives power whenever the power cord

is connected to a power source. Therefore, if the instrument has just been connected to a power source, the frequency of the reference signal may drift until the oscillator stabilizes. Specifications for the stability of the standard internal timebase and the optional Oven Timebase are provided in Chapter 3.

2. Connect the input signal to the appropriate input connector (Counter Channel 1, Counter Channel 2, Power Meter input, or DVM input).

3. Connect an external reference signal to the External Reference

connector on the back panel (if desired).

4. Press the Chan Select key, the Display Power key, and/or the Display DVM key to select the measurement function (if necessary).

5. Press the Freq Offset key and/or the Power Meter Offset On/Off key(s) to enable offset measurements (if desired), and then use the Freq Offset (Shift + Resol) and/or Pwr Offset (Shift + Avg) keys to enter the offset values.

6. Use the Resol, Rate (Shift + +/–), and Avg keys to configure the display.

7. Use the Menu (Shift + Reset/Local) key to set the reference-oscillator source, to select the Channel 1 low-pass filter, to configure the Counter’s response to frequency modulation, to select a Power Meter head, and/or to select a previously saved set of user settings.

8. If you intend to operate the instrument remotely using the GPIB, use the Menu (Shift + Reset/Local) key to set the GPIB address.

9. If you intend to operate the instrument remotely using the serial interface, use the Menu (Shift + Reset/Local) key to adjust the serial port Baud rate.

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Enter

Using the Selection Keys

There are six Selection keys—four “arrow” keys, the Enter key, and the sign (+/–) key. The functions of the arrow keys depend on the instrument’s operating mode (i.e., sequencing through choices in the Menu, numeric entry, state change, etc.). This section describes how the Selection keys function in these different operating modes.

Sequencing Through the Menu

To access the Menu, press the Shift key, and then press the Menu (Reset/Local) key.

Reset/ Local

• Press the up- or down-arrow key to go forward to the next menu function or back to the previous menu function. Pressing either of these keys repeatedly cycles through the list of menu functions.

Shift

• Press the right-arrow key to select a function. When you do this, the flashing annunciator ( ) changes direction and the current setting flashes to indicate that you can now use the up- and down-arrow keys to cycle through the available settings.

• Press the up- or down-arrow key to move through the list of available settings for a function. Pressing either of these keys repeatedly cycles through the list of settings.

• Press the Sign (+/–) key to change the sign of numeric values.

• Press the Enter key to accept the currently displayed setting and exit

the Menu.

NOTE In most cases, when you reach the top or bottom of a list of settings, or the

left or right end of a numerical field, the focus rolls over to the opposite end of the list of settings, or wraps around to the opposite end of the numeric field. In some situations, however, this does not occur, because if it did, you could choose an illegal setting. For these settings, you have to use the opposite button to cycle back through the values or settings.

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Enter

Using the Selection Keys

Numeric Entry

Several menu functions, and several functions that have dedicated keys on the front panel, require you to enter numeric values.

• Press the (left-arrow) and (right-arrow) keys to move left and right to select adjustable digits (the selected digit flashes).

• Press the (up-arrow) and/or (down-arrow) key to increment and decrement the selected (flashing) digit of the displayed value (see note on previous page).

• Press the Sign (+/–) key to change the sign of the numeric value.

• Press the Enter key to complete a numeric entry. (If you change the

value of a numeric entry, but you forget to press the Enter key, the value of the entry is not changed.)

Changing States

Several menu functions, and several functions that have dedicated keys on the front panel, require you to choose from a list of available states.

These functions and the states you can choose for each of them are:

• Reference Oscillator (REF OSC)

– Internal (INT)

–External (EXT)

• Serial Port Baud Rate (BAUD)

– 1200

– 2400

– 4800

– 9600

– 14400

– 19200

• Frequency Modulation (FM)

– Automatic (AUTO)

–Off (OFF)

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Using the Selection Keys

• Channel 1 Low-Pass Filter (CH1 LPF)

–On (ON)

–Off (OFF)

• Measurement Rate (Rate key)

–Fast (FAS T)

–Medium (MED)

–Slow (SLOW)

–Hold (HOLD)

• Resolution (Resol key)

– 1 Hz, 10 Hz, 100 Hz, 1 kHz, 10 kHz, 100 kHz, 1 MHz

Use the Selection keys as described below to change the state of these functions:

• When the annunciator ( ) in the display flashes, press the right-arrow key to move the focus from the displayed menu function (or frontpanel-key function) to the setting for that function.

• Press the up- or down-arrow key to cycle through the available choices.

Press the Enter key to complete the setting. (If you change the setting of a function, but you forget to press the Enter key, the setting of the function is not changed.)

NOTE The Sign key has no function and is ignored in menu selections and

front-panel functions that have state-change selections only.

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Reset/ Local

Freq Offset

On/Off

Clear

Resol

Shift

Using the Clear and Reset/Local Keys

The Clear and Reset/Local keys have similar functions in the Menu and in other front-panel-key function settings, but their effects vary with the instrument’s state and condition. In general, the Reset/Local key restores the setting that was in effect when you entered the Menu or frontpanel-key function, but it does not close the Menu or the function-setting display. The Clear key also restores the previous setting, but it closes the Menu or the front-panel-key function-setting display at the same time.

If you press the Reset/Local key while the instrument is taking measurements, it resets the current operation and forces the instrument to reacquire and re-measure the signal.

Pressing the Reset/Local key while the instrument is in Remote Mode forces the instrument into Local Mode and enables all of the front-panel controls.

Acknowledging Messages

When a message is displayed, press the Reset/Local key, the Clear key, or the Enter key (after reading the message) to acknowledge it and erase it from the display.

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MODIFY

Cal Factor

Freq Offset

On/Off Rate

Freq

Pwr Offset

Avg

+/-+/-Clear

Resol

Enter

Cal Factor

Freq Offset

On/Off Rate

Freq

+/-+/-Clear

Resol

COUNTER

Offset On/Off

Rel Freq

Other Function Selection Keys

There are several functions that you access directly from front-panel keys (not from within the Menu). These functions, which are all in the MODIFY section of the front panel, are:

• Display Resolution (Resol key)

• Frequency Offset (Freq Offset — Shift + Resol key)

• Frequency (Freq key)

• Calibration Factor (Cal Factor — Shift + Freq key)

• Measurement Rate (Rate — Shift + +/– key)

• Number of Averages (Avg key)

• Power Offset (Pwr Offset — Shift + Avg key)

Use the Selection keys in the manner described earlier in this chapter (see “Numeric Entry” and “Changing States”) to adjust the settings for these functions. Detailed procedures for using the Resol, Freq Offset,

Freq, Cal Factor, Rate, and Avg keys are provided later in this chapter.

Chan Select

Gate

There are also a number of functions that are toggled between states (no selections or numerical-entry fields are displayed) using named front-panel keys. These are:

• Display backlight on or off (MODIFY: On/Off). Press Shift, and then press On/Off (the Clear key in the MODIFY section of the front panel).

• Frequency channel selection (COUNTER: Chan Select). Press the Chan Select key in the COUNTER section of the front panel to toggle

between the two Counter input channels.

• Frequency offset measurement (COUNTER: Offset On/Off). Press the Offset On/Off key in the COUNTER section of the front panel to turn

the frequency offset function on or off.

• Relative frequency measurement (COUNTER: Rel Freq). Press the Rel Freq key in the COUNTER section of the front panel to measure

the difference in frequency between the current measurement and the measurement taken at the time you pressed the Rel Freq key (drift).

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POWER METER

Display Power

dBm/W

Store

Cal

Zero

Offset On/Off

Rel Pwr

–

DAMAGE

±60 VDC

Display DVM

Other Function Selection Keys

• Display power measurement (POWER METER: Display Power).

Press the Display Power key in the POWER METER section of the front panel to turn the power measurement function on and off.

• Power offset (POWER METER: Offset On/Off). To turn the power offset function on or off, press the Offset On/Off key in the POWER METER section of the front panel (Display Power must be selected).

• Relative power measurement (POWER METER: Rel Pwr — Shift + Offset On/Off). Press Shift, and then press the Rel Pwr key (the Offset On/Off key in the POWER METER section of the front panel) to

measure the difference in power between the current measurement and the measurement taken at the time you pressed the Rel Pwr key.

• Unit of measurement for power (POWER METER: dBm/W — Shift + Display Power). To toggle between measuring power in dBm and in Watts, press the Shift key, and then press the dBm/W key (the Display Power key in the POWER METER section of the front panel).

• Display voltage measurement (DVM: Display DVM). Press the Display DVM key in the DVM section of the front panel to turn the voltage

measurement function on and off.

NOTE The Counter is active by default, so the Display DVM key toggles the

upper portion of the display between voltage measurement and frequency measurement. Frequency and power measurements can be displayed simultaneously, as can voltage and power measurements. Frequency measurements and voltage measurements can be displayed alone, but power measurements are always accompanied by either the frequency display or the voltage display.

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Measuring Frequency

Battery

Measuring Frequency

1 Connect the instrument to a power source.

When the instrument is connected to an AC power source, the Standby indicator on the front panel lights. The Standby indicator also lights if the

Battery Charging

EXT DC

11 to 18 VDC

POWER

Standby

CAUTION The Channel 2 input path circuits contain sensitive GaAs semiconductors.

instrument is connected to an external DC power source or is operated from internal batteries and the battery power switch is on (with the Battery option only).

2Press the POWER button on the front panel.

The Standby indicator goes off, and all segments of the front-panel display are temporarily activated. TESTING is displayed while the instrument performs its power-on self-test. If the instrument passes all of the tests, SELF TEST OK is displayed, and the instrument then displays its model number, firmware version number, GPIB address, and CH2 NO SIGNAL. The Counter is now ready to measure the frequency of a signal applied to the Channel 2 input. Note that the Ch 2 and Freq annunciators are activated.

3 Connect an input signal to Channel 2.

To prevent damage to these components, always adhere to standard ESD (ElectroStatic Discharge) prevention procedures, and ensure that the maximum power specification for this channel (+27 dBm) is not exceeded.

COUNTER

CHANNEL 2

50MHz to 26.5 GHz

DAMAGE

+27 dBm

50Ω

The Counter automatically displays the measured frequency of the input signal. To set the resolution, measurement rate, and/or the number of averages, see the appropriate procedure in the section titled “Operating the Instrument,” or refer to “Setting the Resolution,” “Setting the Measurement Rate,” and “Setting the Number of Averages,” later in this chapter.

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Measuring Frequency

NOTE When the frequency of a signal applied to the Channel 2 input exceeds

the maximum rated frequency for the Counter, the Counter displays CH2 TOO HIGH.

4 To measure the frequency of a signal applied to the Channel 1

input, press the Chan Select key.

CHANNEL 1 is displayed momentarily, and the Ch 1 and Freq annunciators are activated. If a signal is presently applied to the Channel 1 input, the measured frequency is then displayed. If no signal is applied, CH1 NO SIGNAL is displayed until an input signal is connected to the

Chan Select

Gate

Channel 1 input connector.

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Setting the Resolution and Measurement Rate

The number of measurements the Counter makes in a given amount of time is affected by the Rate setting, the Resolution setting, and the quality of the input signal (signal quality affects the amount of time the Counter requires to determine an accurate measurement). By adjusting the Resolution and Rate settings, you can affect how often the Counter takes measurements.

Setting the Resolution

The Counter’s resolution setting determines the number of digits displayed for measurements and the precision of the measurements. Since less time is required to compute each measurement as the resolution of the measurements is reduced, the resolution setting also affects the rate at which measurements are taken and displayed. As a result, the flash rate of the Gate indicator changes when you change the resolution.

The numerals shown for the value of the measurement are displayed in four groups of three digits, as shown below (the leading zero is suppressed):

Ch 2

Freq

GHz

MHz

kHz

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Reset/ Local

Freq Offset

On/Off

Clear

Resol

Shift

Enter

Setting the Resolution and Measurement Rate

Resolution Setting Example

For the following example, use the 10 MHz output from the reference timebase as the input to Channel 1.

1 Press the Resol key to enter the resolution-setting mode.

The current resolution setting is displayed (the current value and the indicator between the arrow keys are flashing to indicate that you can use the up- and down-arrow keys to change the setting).

2 Press the up-arrow or down-arrow key to decrease or increase

the resolution.

You can press these keys as many times as necessary to locate the setting you want to use. The available resolution settings are 1 Hz (the default), 10 Hz, 100 Hz, 1 kHz, 10 kHz, 100 kHz, and 1 MHz.

3Press the Enter key to activate your setting and exit the

resolution-setting mode.

The setting you chose is now in effect. The number of digits displayed for the measurement is adjusted accordingly; you can observe the affect on measurement speed by monitoring the flash rate of the Gate indicator.

NOTE The measurement resolution has a direct effect on the amount of time the

Counter requires to complete a measurement. Measurements made at the Counter’s maximum resolution setting (1 Hz) are noticeably slower than at lower resolutions. This is especially noticeable when the Counter is set to average a number of measurements.

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MODIFY

Cal Factor

Enter

Avg

+ / -

Freq

Rate

Pwr Offset

Hold

Setting the Resolution and Measurement Rate

Setting the Measurement Rate

The measurement Rate setting determines how frequently the instrument initiates measurements (frequency, power, and/or voltage). Since the actual measurement rate is also affected by the Counter’s resolution setting and the signal quality, as mentioned earlier, the available rate settings (FAST, MED, and SLOW) do not equate to a fixed number of measurements in a given amount of time. The HOLD setting turns off automatic measurements, so that a single measurement is made each time you press the Reset/Local key.

Rate Setting Example

1 Press the Rate key to enter the rate-setting mode.

The current rate setting is displayed (the current value and the indicator between the arrow keys are flashing to indicate that you can use the upand down-arrow keys to change the setting).

2 Press the up-arrow or down-arrow key to decrease or increase

the measurement rate.

You can press these keys as many times as necessary to locate the setting you want to use. The available resolution settings are FAST, MED, SLOW, and HOLD.

3Press the Enter key to activate your setting and exit the rate-

setting mode.

The setting you chose is now in effect. The measurement rate is adjusted accordingly; you can observe the effect on measurement speed by monitoring the flash rate of the Gate indicator. The rate annunciator is activated when either SLOW or MEDIUM is selected for the rate. When you select HOLD, the HOLD annunciator is activated.

4 If you set the rate to HOLD, press the Reset/Local key to initiate

a measurement.

The instrument computes the measurement and then displays the result (if averaging is enabled, the instrument displays the AVERAGING message while it computes the measurement). Press the Reset/Local key again each time you want to take an additional measurement.

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Pwr Offset

+/–

Avg

Setting the Number of Averages

You can set the instrument to take a variable number of frequency, power, or voltage measurements and average them mathematically before displaying the result. You can use this feature to determine the effective measurement of a signal that is fluctuating. When measuring the frequency of a fluctuating signal, you can also use averaging to retain some of the precision of a maximum-resolution measurement.

The default number of averages is 1, which means that no averages are performed, and the maximum setting is 99. Note that the tens position (10 through 90) and the units position (0 through 9) are adjusted separately, and that it is not possible to set the number of averages to 0.

NOTE When a large number of averages is selected for a frequency measurement

in combination with a high resolution setting (e.g., 1 Hz), it takes a considerable amount of time for the instrument to take the measurements, compute the averages, and display an initial reading. For example, when

the number of averages is set to 60, and the resolution is set to 1 Hz, the first reading is displayed after 60 seconds (approximately). Subsequent computations do not require as much time, since the averaging function computes a running average. However, the rate at which the display is updated after the initial average computation is also slower than at lower resolution settings.

Averages Setting Example

1 Press the Avg key to enter the averages-setting mode.

The current averages setting is displayed (the current value and the indicator between the arrow keys are flashing to indicate that you can use the up- and down-arrow keys to change the setting).

2 Press the up-arrow or down-arrow key to decrease or increase the

value for the units position of the number of averages.

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Ch 12

Rel Freq

Avg On

Setting the Number of Averages

NOTE For most of the instrument’s settings, when you continue to press either

the up-arrow or the down-arrow key when you reach the end of the available settings, the value for the setting “rolls over” to the value at the opposite end of the range. For example, if the GPIB address is set to 31, and you press the up-arrow key, the value changes to 1. However, when you adjust the value in the units position for the number of measurements to be averaged, rollover does not occur. If you press the up-arrow when the value in the tens position is 0 and the value in the units position is 9, or if you press the down-arrow when the value in the tens position is 0 and the value in the units position is 1, there is no change. If the value in the units position could roll over (in either direction), it would allow you to set a value of 0 for the number of averages. Since at least one measurement must be taken, 0 is an illegal value.

3 Press the left-arrow key once to move the focus to the tens

position, and then use the up- and/or down-arrow key to set the value for the tens position (if desired).

Note that the tens and units values are set separately.

4Press the Enter key to activate your setting and exit the averages-

setting mode.

The Avg On annunciator is activated, and the instrument displays AVERAGI N G while it takes the first set of measurements. The length of

time that the AVERAGING message is displayed varies primarily with setting for the number of averages, since this determines the number of measurements that must be made and averaged before displaying a result. When the first set of averages is complete and the result is displayed, the instrument immediately takes another measurement, discards the oldest measurement included in the current average computation, recomputes the average and displays the new result. This continues until you change the setting for the number of averages or disable averaging (by setting the number of averages to 0).

In certain situations, the length of time that the AVERAGING message is displayed can be affected by additional factors. When you are measuring frequency, the current resolution setting, the rate setting, and the quality of the signal all affect the length of time required to make the measurements and complete the average computation.

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Setting the Number of Averages

NOTE If the measurement rate is set to HOLD, and a value larger than 1 is set

for averages, the first set of measurements is not initiated until you press the Reset/Local key. When you do, the instrument displays the AVERAGING message while it takes the first set of measurements. When the first set of measurements is complete, and the averaging result is displayed, the instrument remains in this state until you press the Reset/Local key to initiate another set of measurements, change the value for averages back to one, or change the setting for the measurement rate to SLOW, MED, or HIGH. When the measurement rate is set to HOLD, the instrument performs a block-average computation instead of a runningaverage computation.

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Measuring Relative Frequency

You can measure the difference in frequency from one measurement to another (frequency drift) or between two separate input signals using the Relative Frequency function.

Relative Frequency Example

Press the Rel Freq key. The Shift annunciator activates when you press the Shift key. When you press the Rel Freq key, the Rel Freq annunciator in the upper-left corner of the display activates. At the same time, the Counter saves the frequency measurement it was displaying at the time you pressed the Rel Freq key, and it computes and displays the difference between the stored measurement and all subsequent measurements until the relative frequency function is deactivated.

You can also use the Relative Frequency function to measure the difference between two different signals. To do this, activate the Relative Frequency function, as described in the previous paragraph, disconnect the cable supplying the signal to the input connector, and then connect the second signal to the same input connector. The value displayed when the Counter acquires the second signal is the frequency difference between the two signals.

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Rel

Offsetting a Frequency Measurement

To display an offset frequency measurement, you need to set the value and sign (+/–) of the offset and to turn the Frequency Offset function on.

Frequency Offset Example

1 Connect a cable from the 10 MHz reference output on the back

panel to the Channel 1 input connector, and press the Chan Select key (if necessary) to activate Channel 1.

The display should look like this:

GHz

Ch 1

Freq

Rel

MHz

kHz

2Press the Shift key, and then press the Freq Offset (Resol) key in the

MODIFY section of the front panel.

The Shift annunciator activates when you press the Shift key. When you press the Freq Offset key, the Shift annunciator disappears, and the Freq

Offset annunciator at the left side of the display activates.

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Rel

Offsetting a Frequency Measurement

3 Use the left- and right-arrow keys to move the focus to the digit(s)

in the frequency-offset display that you need to adjust to enter the offset value, and then use the up- and down-arrow keys to adjust the value for each digit. Enter a value of 500 Hz.

The flashing digit is the digit that currently has the focus. This means that you can change the value of the flashing digit using the up- and down-arrow keys.

4 Press the sign (+/–) key (if desired) to change the sign of the

offset value.

The display should look like this:

GHz

Ch 1

Freq

Rel Offset

MHz

kHz

5Press the Enter key to confirm the offset value and exit the

offset-entry display.

The Freq Offset annunciator is deactivated, and the measurement display returns.

NOTE When you are entering a value for Frequency Offset (or Power Offset),

you can use the Reset key to restore all of the displayed digits to zero. These are the only two functions in which the Reset key has this effect.

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Offsetting a Frequency Measurement

6Press the Offset On/Off key in the COUNTER section of the

front panel.

The Freq Offset annunciator is activated, and the value of the display is adjusted to reflect the value and sign of the offset entered in Steps 2 and 3.

The display should look like this:

Ch 1

Rel Freq

Offset

GHz

MHz

kHz

Since the offset function can be used to add or subtract a fixed value to/from the measurement result, you can use this feature to tune or align the odd frequencies of a local oscillator (LO). If you enter the target

frequency as a negative offset, the Counter displays the difference between the LO’s frequency and the target frequency. You can then adjust the LO until the Counter displays a value of zero.

NOTE The maximum value that can be entered for Frequency Offset is

± 49,999,999,999 Hz.

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Measuring Power

The Agilent 53147A/53148A/53149A can measure signal power in the power and frequency ranges listed in the specifications in Chapter 4. The power measurement, which is shown in a dedicated area of the display, includes a digital readout and an analog representation. The display, which can be configured to show power in units of dBm or Watts, is auto-ranging when set to measure in Watts.

Selecting a Power Head (Sensor)

There are a number of Agilent power heads that can be used with the Power Meter in this instrument. Choosing the appropriate power head is a matter of matching the head’s characteristics to the signal to be measured.

Before you can make any power measurement, you must determine which power head (sensor) to use for the measurement, select the power head in the instrument’s menu (see “Using the Menu” on page 2-43), and configure the Power Meter to use the appropriate calibration factor for the frequency of the signal. The five power head models that have prerecorded calibration-factor tables in the instrument’s non-volatile memory are listed under “Power Head Selection (HEAD)” on page 2-50.

You can also modify the data points (frequency/calibration-factor data pairs) in the preconfigured calibration-factor tables, add data points to these tables, and add up to three custom tables for power heads that are not included in the instrument’s menu. Instructions for modifying and adding data points in calibration-factor tables are provided in “Modifying and Adding Calibration Factor Tables” on page 2-27.

Making a Power Measurement

When you turn the Power Meter on, you must always zero and calibrate it with the power head connected before making any measurements. If you are using a different model power head than the one used the last time the Power Meter was used, you must also set the power head model in the instrument’s menu. As part of the measurement sequence, you must input either the frequency of the signal you intend to measure or the power factor for that frequency (from the table provided with the power head).

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Measuring Power

NOTE You must re-zero and recalibrate the Power Meter if you change the power

head, if the instrument is shut off for any period of time, if the ambient temperature changes by 5

° C (9° F) or more, and if the GPIB “INIT”

command is sent to the instrument. In any case, you should calibrate the Power Meter at least once a day.

CAUTION Always follow the directions provided with the power head in addition to

the instructions provided in this manual.

Power Measurement Example

NOTE The instrument must be powered on and must remain at the same ambient

temperature for 15 minutes before beginning this procedure. If the temperature changes by 5° C (9° F) or more, wait another 15 minutes.

1 Connect the output cable from the power-meter head to the

Power Meter Input connector.

This example assumes that you have a power head available that is appropriate for the measurement to be taken.

2Press the Display Power key to enable power measurement.

The Pwr annunciator at the left side of the display is activated, and the Power Meter’s digital and analog power displays show the power measurement in dB or dBm (the default units of power measurement).

The display should look like this:

Ch 2

Freq

dBm

Pwr

Watts mW uW %

NOTE When there is no signal applied to the power head, the Power Meter

reads the noise level, as shown in the illustration above. This reading is generally below –25 dBm prior to zeroing and will vary.

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NOTE The upper portion of the display may show a frequency measurement or a

voltage measurement if a signal is applied to the Counter or DVM input and the Counter or DVM is enabled. In this example, the Counter is enabled, but no signal is applied, so the upper portion of the display shows CH2 NO SIGNAL. If the DVM is enabled with no signal applied, the upper portion of the display will show VDC 0.000.

3Press the Shift key, and then press the Menu (Reset/Local) key.

One of the items in the instrument’s menu is displayed (if the menu has not been used since the instrument was turned on, the initial menu display is “REF OSC> INT”).

4 Use the up and/or down arrow keys to cycle through the menu

until “HEAD > OFF” is shown.

Note that a power head model number may appear instead of “OFF” if a power head was previously chosen.

5 Press the right arrow key.

The flashing indicator after HEAD changes from to , and “OFF” (or the currently selected power head model number) begins to flash.

6 Select the model number of the power head you intend to use by

pressing the up- and/or down-arrow key repeatedly until the correct model number is displayed, and then press Enter.

NOTE You can change the values of the frequency/power-factor data points that

are stored in the instrument’s memory (or add data points) by pressing the right-arrow key while a power-head model number is displayed and pressing the right-arrow key again when “LIST” is displayed. For instructions on entering or changing data, see “Numeric Entry” on page 2-6.

The instrument is shipped with calibration tables in nonvolatile memory for five of the supported power heads. The data points in these tables are almost always sufficient to provide accurate readings, so it is usually unnecessary to add or modify the values in the tables.

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NOTE Three empty tables are provided for compatible power-sensor heads that

the instrument does not have pre-recorded tables for. You can create your own table by entering a set of frequency/power-factor data points for a power head by selecting CUST 1, CUST 2, or CUST 3 from the HEAD menu. You then enter a set of frequency/power factor data points for the power head. For instructions on entering or changing data, see “Numeric Entry” on page 2-6.

7Press the Zero key.

The Power Meter displays ZEROING and then returns to the display shown in Step 2.

8 Connect the power-head input connector to the Power Meter

Output connector.

9Press the Cal key.

During calibration, the Power Meter displays CALIBRATING. It then

returns to the display shown in Step 2.

10 If you know the frequency of the signal you intend to measure,

press the Freq key, enter the frequency value, and press Enter (for instructions on entering or changing values, see “Numeric Entry” on page 2-6).

The Power Meter uses the frequency to set the power-factor per the values in the stored calibration tables. If you prefer, you can use the Cal Factor key to enter the calibration factor value directly.

NOTE If the signal you intend to measure is already applied to one of the Counter’s

input channels, you can press the Store key (Shift + Cal) to input the frequency value instead of using either the Freq or Cal Factor keys and entering a value manually. This saves time and has the same effect.

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Measuring Power

11 Disconnect the power-head input connector from the Power Meter

Output connector and connect it to the signal to be measured.

The Power Meter measures the signal power and displays it, as shown below:

Ch 2

Freq

dBm

Pwr

Watts mW uW %

12 To measure the signal power in Watts, press the Shift key, and

then press the dBm/W (Display Power) key.

When you press the Shift key, the Shift annunciator is activated. When you press the dBm/W (Display Power) key, the Shift annunciator goes off, and the units of measurement annunciator group to the right of the digital power measurement changes from dB or dBm to Watts, mW, µW, or nW, as shown below:

Ch 2

Freq

dB dBm

Rel Pwr

Watts

uW %

Modifying and Adding Calibration Factor Tables

The HEAD menu option provides access to preconfigured, editable calibration-factor tables for five models of Agilent power-sensor heads (models 8481A, 8481D, 8482A, 8485A, and 8487A) and three custom tables. You can modify the frequency/calibration-factor values in any of the data points for any power head, and you can input data to build new calibration tables (CUST 1, CUST 2, and CUST 3). Table 2-1 shows the changes you can and cannot make to the various data points in the five factory-configured calibration-factor tables (for models 8481A, 8481D, 8482A, 8485A, and 8487A) and the three custom calibration tables (CUST 1,

CUST 2, and CUST 3).

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Table 2-1. Calibration Factor Data Point Modifications

Calibration Table Data Points Modify Delete Reset Add

Factory defined data points (for 8481A, 8481D, 8482A, 8485A, and 8487A)

Data points added to factory-defined tables by user

Custom calibration-factor tables (CUST1, CUST2, and CUST3)

All None All Yes

All All N/A N/A

All All N/A Ye s

Calibration Table Modification Example

This example demonstrates how to view and modify the values in any of the preconfigured calibration tables or in one of the three custom calibration tables.

1Press the Shift key, and then press the Menu (Reset/Local) key.

One of the items in the instrument’s menu is displayed (if the menu has not been used since the instrument was turned on, the initial menu display is “REF OSC> INT”).

2 Use the up and/or down arrow keys to cycle through the menu

until “HEAD > OFF” is shown.

Note that a power head model number (or CUST 1, CUST 2, or CUST 3) may appear instead of “OFF” if a power-head model was previously selected.

3 Press the right arrow key.

The flashing indicator after HEAD changes from to , and “OFF” (or the currently selected power head model number) begins to flash.

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4 Select the model number of the power head you intend to modify

the data point(s) for by pressing the up- and/or down-arrow key repeatedly until the correct model number is displayed, and then press Enter.

You can now change the values of the frequency/power-factor data points that are stored in the instrument’s memory (or add data points) by pressing the right-arrow key while a power-head model number is displayed and pressing the right-arrow key again when “LIST” is displayed. For instructions on entering or changing data, see “Numeric Entry” on page 2-6.

5 Press the right arrow key.

The display scrolls right-to-left and displays LIST and the frequency (on the top line) and calibration-factor (on the bottom line) values in the first data point. You can now use the up and down arrow keys to cycle through the data points in the currently displayed calibration table.

Ch 2

Freq

Offset

Avg On

Pwr

Offset

dB dBm Watts mW uW

6 Press the right arrow key again.

The flashing indicator after LIST changes from to , and the first digit in the frequency value begins to flash. You can now use the up and down arrow keys to change the value of the first digit of the frequency value.

Ch 2

Freq

Offset

Avg On

Pwr

Offset

dB dBm Watts mW uW

You can also use the right and left arrow keys to move between the digits of the frequency value and use the up and down arrow keys to change the values of these digits.

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NOTE In instruments that have firmware that is modified as described in Service

Note 53147/8/9A-01, you can change the instrument’s setting to match

the 50 MHz reference calibration factor (RCF) of your power head. When the frequency reading on the display is 00.05 GZ (50 MHz), you can change the RCF to the one for your particular power head. After doing this, always re-zero and recalibrate the instrument (see Steps 7 through 9 on page 2-26).

All units shipped from the factory after August 2001 have the modified firmware installed. To determine whether your instrument has the modified firmware, display the menu as described in “Sequencing Through the Menu” on page 2-5. The instrument’s model number is listed between the Preset and Op Hours menu items. Press the right arrow key once to display the model number. If your instrument’s model number is any number lower than 2060166-99, you should obtain and install the firmware kit (Agilent part number 53147-80018).

7 When you move the focus to the last digit of the frequency value

(the one furthest to the right), an additional flashing indicator ( )

appears at the right end of the display, and the indicator to the left of the frequency value ( ) stops flashing.

Ch 2

Freq

Offset

Avg On

Pwr

Offset

dB dBm Watts mW uW

This indicates that, in addition to being able to use the up and down arrow keys to adjust the value of the flashing digit in the frequency value, you can also press the right arrow key to move the focus from the last digit of the frequency value to the first digit of the calibration-factor value.

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8 Press the right arrow key until the focus moves from the last

digit of the frequency value to the first digit of the calibrationfactor value (the first calibration-factor digit begins flashing). The flashing indicator at the right of the frequency value changes direction (from to ), which indicates that you can use the left arrow to return to the frequency value, if you need to.

Ch 2

Freq

Offset

Avg On

Pwr

Offset

dB dBm Watts mW uW

You can now use the left and right arrow keys to move between the digits of the calibration-factor, and you can use the up and down arrow keys to adjust the values of the individual digits of the calibration-factor.

9 If you want to change values in additional data points, press the

right arrow key to save your changes and move to the next data point. If you are done changing data point values, press the Enter key to save your changes and exit the menu.

Whether you save and move to the next data point or save and exit, all of the data points in the current table are immediately resorted into order by frequency. This is important to keep in mind, since the next data point in order may no longer be the same one that was in that position in the list before you made changes to the data point you just adjusted.

NOTE You can use the same steps to create a calibration table for a power head

model that the Power Meter does not have a preconfigured calibration table for, or you can create an alternate calibration table for one of the five power head models that does have a preconfigured table. To do this, simply choose CUST 1, CUST 2, or CUST 3 from the HEAD menu option instead of choosing one of the preconfigured tables identified with a power-head model number.

NOTE To delete a data point entirely, set the calibration-factor to a value of 50 or

lower. When you move to the next data point or exit the menu, the data point containing the =< 50 value is automatically deleted from the table.

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Table 2-2 lists the factory-set values in all of the data points for all five of the pre-recorded power head calibration tables.

Table 2-2. Calibration Table Data-Point Values

Power Head Model Number Frequency Calibration Factor

8481A

RCF 100.0

50 MHz 100.0

100 MHz 99.8

2 GHz 99.0 3 GHz 98.6 4 GHz 98.0 5 GHz 97.7 6 GHz 97.4 7 GHz 97.1 8 GHz 96.6

9 GHz 96.2 10 GHz 95.4 11 GHz 94.9

12.4 GHz 94.3 13 GHz 94.3 14 GHz 93.2 15 GHz 93.0 16 GHz 93.0 17 GHz 92.7 18 GHz 91.8

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Table 2-2. Calibration Table Data-Point Values (continued)

Power Head Model Number Frequency Calibration Factor

8481D

RCF 99.0

50 MHz 99.0

500 MHz 99.5

1 GHz 99.4 2 GHz 99.5 3 GHz 98.6 4 GHz 98.6 5 GHz 98.5 6 GHz 98.5 7 GHz 98.6 8 GHz 98.7

9 GHz 99.5 10 GHz 98.6 11 GHz 98.7 12 GHz 99.0

12.4 GHz 99.1 13 GHz 98.9 14 GHz 99.4 15 GHz 98.9 16 GHz 99.1 17 GHz 98.4 18 GHz 100.1

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Table 2-2. Calibration Table Data-Point Values (continued)

Power Head Model Number Frequency Calibration Factor

8482A

RCF 98.0

0.1 MHz 98.0

0.3 MHz 99.5 1 MHz 99.3 3 MHz 98.5

10 MHz 98.5

30 MHz 98.1 100 MHz 97.6 300 MHz 97.5

1 GHz 97.0

2 GHz 95.0

3 GHz 93.0

4.2 GHz 91.0

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Table 2-2. Calibration Table Data-Point Values (continued)

Power Head Model Number Frequency Calibration Factor

8485A

RCF 100.0

50 MHz 100.0

2 GHz 99.5 4 GHz 98.9 6 GHz 98.5

8 GHz 98.3 10 GHz 98.1 11 GHz 97.8 12 GHz 97.6

12.4 GHz 97.6 14 GHz 97.4 16 GHz 97.0 17 GHz 96.7 18 GHz 96.6 19 GHz 96.0 20 GHz 96.1 21 GHz 96.2 22 GHz 95.3 23 GHz 94.9 24 GHz 94.3 25 GHz 92.4 26 GHz 92.2

26.5 GHz 92.1

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Table 2-2. Calibration Table Data-Point Values (continued)

Power Head Model Number Frequency Calibration Factor

8487A

RCF 100.0

50 MHz 100.0 100 MHz 99.9 500 MHz 98.6

1 GHz 99.8 2 GHz 99.5 3 GHz 98.9 4 GHz 98.8 5 GHz 98.6 6 GHz 98.5 7 GHz 98.4 8 GHz 98.3

9 GHz 98.3 10 GHz 98.3 11 GHz 98.1 12 GHz 97.9 13 GHz 98.0 14 GHz 98.2 15 GHz 97.7 16 GHz 96.8 17 GHz 97.0 18 GHz 96.3 19 GHz 95.9 20 GHz 95.2 21 GHz 95.6 22 GHz 95.5 23 GHz 95.4 24 GHz 95.0 25 GHz 95.4 26 GHz 95.2 27 GHz 95.1 28 GHz 95.0 29 GHz 94.4 30 GHz 94.0 31 GHz 93.7

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Table 2-2. Calibration Table Data-Point Values (continued)

8487A (continued)

32 GHz 93.8 33 GHz 93.0 34 GHz 93.2

34.5 GHz 93.5 35 GHz 93.1 36 GHz 92.0 37 GHz 92.4 38 GHz 90.9 39 GHz 90.3 40 GHz 91.4 41 GHz 90.6 42 GHz 89.9 43 GHz 89.1 44 GHz 88.1 45 GHz 86.9 46 GHz 85.8 47 GHz 85.4 48 GHz 83.2 49 GHz 81.6 50 GHz 80.2

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Ch 12

Rel Freq

Rel Pwr

Measuring Relative Power

You can measure the difference in power from one measurement to another or between two separate input signals using the Relative Power function.

Relative Power Example

Press the Shift key, and then press the Rel Pwr (POWER METER: Offset On/Off) key. The Shift annunciator activates when you press the Shift key.

When you press the Rel Pwr key, the Shift annunciator disappears, and the Rel Pwr annunciator at the left side of the display activates. At the same time, the Power Meter saves the power measurement it was displaying at the time you pressed the Rel Pwr key, and it computes and displays the difference in power between the stored measurement and all subsequent measurements until the relative power function is deactivated.

NOTE When the Power Meter is set to measure power in dBm, relative power is

expressed in dB. When the Power Meter is set to measure power in Watts,

relative power is expressed as a percentage (%).

You can also use the Relative Power function to measure the difference in power between two different signals. To do this, activate the Relative Power function, as described in the previous paragraph, disconnect the signal to the power head (sensor), and then connect the second signal to the same power head. The value displayed when the Power Meter acquires the second signal is the power difference between the two signals.

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Offsetting a Power Measurement

You can use the power offset (Pwr Offset) function to add or subtract a constant value to/from a power measurement. For example, you can use an offset to compensate for a systematic error, to display the difference in power between two signals, or to compensate for losses and attenuation in cables or components that are between the signal source and the Power Meter.

To display an offset power measurement, you set the value and sign (+/–) of the offset and turn the Power Offset function on.

Power Offset Example

1 Connect a signal to the Power Meter input connector, and activate

power measurement by pressing the Display Power key.

The display should look like this (the values are simulated in these illustrations):

Ch 2

Freq

dBm

Pwr

Watts mW uW %

2Press the Shift key, and then press the Pwr Offset (Avg) key.

The Shift annunciator activates when you press the Shift key. When you press the Pwr Offset key, the Shift annunciator and the frequency display disappear, the Pwr Offset annunciator at the left side of the display activates, and the power-offset value is set to 00.00, as shown below:

Ch 12

Rel Freq

Rel Pwr

Offset

Watts mW uW %

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NOTE If the power-offset value was previously changed, the previous value is

displayed instead of 00.00.

3 Use the left- and right-arrow keys to move the focus to the digit(s)

in the power-offset display that you need to adjust to enter the offset value, and then use the up- and down-arrow keys to adjust the value for each digit.

The flashing digit is the digit that currently has the focus. This means that you can change the value of the flashing digit using the up- and down-arrow keys.

4 Press the sign-change (+/–) key (if desired) to change the sign of

the offset value.

Ch 12

Rel Freq

dBm

Rel Pwr

Offset

Watts mW uW %

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5Press the Enter key to confirm the offset value and exit the offset-

entry display.

The Pwr Offset annunciator is deactivated, and the measurement display returns.

6Press the Offset On/Off key (in the POWER area of the front panel).

The Pwr Offset annunciator is activated, and the value of the display is adjusted to reflect the value and sign of the offset entered in Steps 3 and 4.

The display should now look like this (values are simulated):

Ch 2

Freq

dBm

Rel Pwr

Offset

Watts mW uW %

NOTE When you are entering a power- or frequency-offset value, you can use the

Reset key to restore all of the displayed digits to zero. These are the only two functions in which the Reset key has this effect.

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Measuring Voltage

The Agilent 53147A/148A/149A included a digital voltmeter (DVM) that can measure voltages from – 50 VDC to +50 VDC. To measure voltage, use the following procedure:

Voltage Measurement Example

1 If the instrument is not already turned on, connect the power

cord to the power-input connector on the rear panel and to an appropriate power source (or, with the Battery option, turn on the Battery power switch).

2Press the Display DVM key in the DVM section of the front panel.

The DVM display is activated, as shown below:

3 Insert the connector on the end of the red test lead into the red

+ DVM connector, and insert the connector on the black test lead into the black – DVM connector.

4 Touch the red and black test prods to the points at which you

want to measure the voltage.

The display should look like this (assuming a voltage source of +2.030 VDC):

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Using the Menu

The Agilent 53147A/148A/149A’s Menu makes it easy to control a number of the instrument’s features and functions. You use the Selection (arrow) keys to navigate to the setting you want to change and then to actually make the changes.

1Press the Shift key and then the Menu (Reset/Local) key to display

the Menu.

When you press the Shift key, the Shift annunciator (near the bottom-right corner of the display) activates. When you press the Menu (Reset/Local) key, the Shift annunciator goes off, and the first menu item is displayed. If you have not previously invoked the Menu since you last turned the instrument on, the first menu item is REF OSC, the Reference Oscillator.

2 Press the right-arrow key to change the setting for the Reference

Oscillator.

The flashing annunciator ( ) in the display reverses direction to indicate that you can now change the setting by pressing either the up-arrow key or the down-arrow key. In the case of the Reference Oscillator function, which has only two possible settings (INTernal and EXTernal), pressing either the up- arrow or the down-arrow has the same effect (it toggles the setting from INT to EXT or from EXT to INT).

NOTE The Counter will not switch to EXT (external) unless a suitable reference

signal is available at the External Reference connector.

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3Press the Enter key to activate the setting and exit the Menu.

The setting you chose is put into effect, and the Menu closes.

If you need to exit the Menu without changing any of the settings, press the Clear key. To restore the setting of any menu item to the setting that was in effect when you opened the Menu, press the Reset/Local key (this restores the original setting for the current menu item but does not close the Menu).

The Menu contains the following items (these items are displayed in the order they are listed if you repeatedly press the up-arrow key after opening the Menu):

• REF OSC — Sets the Counter to use the internal timebase (INT) or an external timebase (EXT) connected to the Reference connector on the back panel.

• PWR REF — Turns the reference signal available on the Power Meter Output connector ON or OFF.

• SAVE — Saves a copy of the current user settings in non-volatile

memory. Nine sets (0 – 8) can be saved, and Set 0 is automatically read on startup.

• RECALL — Reads and implements a stored set of user settings from one of nine (0 – 8) that are stored in non-volatile memory.

• CH1 LPF — Turns the Channel 1 Low-Pass Filter (approx. 50 kHz) ON or OFF.

• FM — Turns the Counter’s ability to compensate for frequency modulation on (AUTO) or OFF.

• BAUD — Sets the data rate for the RS-232 serial port (1200, 2400, 4800, 9600, 14400, or 19200).

• PRESET — Resets all functions to the factory-default settings.

• Model number, firmware version number, serial number, OPTNS

(installed options).

• OP HRS — Displays the total number of hours the instrument has been in operation since it was last calibrated.

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