Giga-tronics 2502B, 2550B, 2508B, 2520B, 2526B Operation Manual

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Giga-tronics 2500B Series Microwave Signal Generators

Operation Manual

2500B Series Microwave Signal Generators

Operation Manual, Part Number 34737, Rev C, June 30, 2011

Giga-tronics 2500B Series Microwave Signal Generators

Date:

July 1, 2011

Serial Number:

1125001

Code:

Warranty

Giga-tronics 2500B Series instruments are warranted against defective materials and workmanship for one year from date of shipment. Giga-tronics will at its option repair or replace products that are proven defective during the warranty period. This warranty DOES NOT cover damage resulting from improper use, nor workmanship other than Giga-tronics service. There is no implied warranty of fitness for a particular purpose, nor is Giga-tronics liable for any consequential damages. Specification and price change privileges are reserved by Giga-tronics.

The information in this manual applies to 2500B Series instruments manufactured after the following date and serial numbers:

For information on previously manufactured instruments, refer to the manual that came with the instrument.

All technical data and specifications in this publication are subject to change without prior notice and do not represent a commitment on the part of Giga-tronics, Incorporated.

CONTACT INFORMATION

Giga-tronics, Incorporated

4650 Norris Canyon Road San Ramon, California 94583 Telephone: 800.726.4442 (only within the United States)

925.328.4650

Fax: 925.328.4700 On the Internet: www.gigatronics.com

Page ii Operation Manual, Part Number 34737, Rev C, June 30, 2011

Giga-tronics 2500B Series Microwave Signal Generators

Low Voltage Directive

73/23/EEC, amended by 93/68/EEC

EMC Directive

89/336/EEC, amended by 93/68/EEC

Electrical Safety

EN61010-1 (1993)

EMC – Emissions and Immunity

EN61326-1 (1997)

Manufacturer’s Name:

Manufacturer’s Address

Giga-tronics, Incorporated

4650 Norris Canyon Road San Ramon, California 94583 U.S.A.

Type of Equipment:

Model Series Number

Microwave Signal Generator

2500B Series

Model Numbers:

2502B, 2508B, 2520B, 2526B, 2540B, 2550B

Regulatory Compliance Information

This product complies with the essential requirements of the following applicable European Directives, and carries the CE mark accordingly.

Declaration of Conformity on file. Contact Giga-tronics at the following;

Giga-tronics, Incorporated

4650 Norris Canyon Road San Ramon, California 94583 Telephone: 800.726.4442 (only within the United States)

925.328.4650 Fax: 925.328.4700

Operation Manual, Part Number 34737, Rev C, June 30, 2011 Page iii

Giga-tronics 2500B Series Microwave Signal Generators

TPCI Number

TPCI Issue Date

Date Entered

Comments

Record of changes to this Manual

Use the table below to maintain a permanent record of changes to this document. Replacement pages are issued as a TPCI (Technical Publication Change Instruction), and must be inserted at the front of the manual’s binder. Remove the corresponding old pages, insert the new pages, and record the changes here. Do the same thing with TPCI pages that are issued after you have received this manual.

Page iv Operation Manual, Part Number 34737, Rev C, June 30, 2011

Giga-tronics Series 2500B Microwave Signal Generators

CHAPTER 1 SAFETY AND MANUAL CONVENTIONS .................................................................................................................... 1

1.1 Unsafe Operating Conditions ........................................................................................................................................ 1

1.2 Safety and Manual Conventions ................................................................................................................................... 1

1.3 Personal Safety Alert ..................................................................................................................................................... 1

1.4 Equipment Safety Alert ................................................................................................................................................. 1

1.5 Notes ............................................................................................................................................................................. 1

1.6 Graphic Symbols for Front Panel Buttons ..................................................................................................................... 2

CHAPTER 2 INTRODUCTION ................................................................................................................................................. 3

2.1 Overview ....................................................................................................................................................................... 3

2.2 Giga-tronics 2500B Microwave Signal Generator Summary ......................................................................................... 3

2.3 Configuration Information ............................................................................................................................................ 4

2.3.1 Special Configurations ........................................................................................................................................... 4

2.4 Receiving and Inspection .............................................................................................................................................. 5

2.5 Prepare the 2500B for Use ............................................................................................................................................ 6

2.5.1 Cooling Considerations .......................................................................................................................................... 6

2.5.2 AC Power Requirements ........................................................................................................................................ 6

2.5.3 Start-up the 2500B ................................................................................................................................................. 7

2.5.4 Reset the 2500B to Factory-Default Values ........................................................................................................... 8

2.5.5 Replace the AC Line Fuse ....................................................................................................................................... 9

2.6 Shipping, Repair, and Calibration ................................................................................................................................ 10

2.6.1 Shipping the 2500B .............................................................................................................................................. 10

2.6.2 Repairs ................................................................................................................................................................. 10

2.6.3 Calibration ............................................................................................................................................................ 10

2.7 2500B Front Panel ....................................................................................................................................................... 11

2.7.1 Menus .................................................................................................................................................................. 14

2.7.2 Menu Structure .................................................................................................................................................... 16

2.7.3 Access the Menus ................................................................................................................................................ 17

2.7.4 Softkeys ................................................................................................................................................................ 17

2.7.5 Modify Menu Parameters .................................................................................................................................... 17

2.7.6 Modify the Step Size ............................................................................................................................................ 18

2.8 2500B Rear Panel ........................................................................................................................................................ 19

CHAPTER 3 CW OPERATION ............................................................................................................................................. 22

3.1 CW Menu Description ................................................................................................................................................. 22

3.2 Generate a CW Signal .................................................................................................................................................. 24

CHAPTER 4 RAMP OPERATION .......................................................................................................................................... 27

4.1 Ramp Menu Description ............................................................................................................................................. 27

4.2 Generate a Frequency-Swept Signal ........................................................................................................................... 34

4.3 Generate a Power-Swept Signal .................................................................................................................................. 35

CHAPTER 5 MODULATION OPERATION ................................................................................................................................ 36

5.1 AM Menu Description ................................................................................................................................................. 36

5.2 Generate an Internally Modulated AM Signal ............................................................................................................ 40

Operation Manual, Part Number 34737, Rev C, June 30, 2011 Page v

Giga-tronics 2500B Series Microwave Signal Generators

5.3 Generate an Externally Modulated AM Signal ............................................................................................................ 41

5.4 FM Menu Description ................................................................................................................................................. 44

5.5 Generate an Internally Modulated FM Signal ............................................................................................................. 50

5.6 Generate an Externally Modulated FM Signal ............................................................................................................ 52

5.7 Generate an Externally Phase Modulated Signal ........................................................................................................ 54

5.8 Pulse Modulation (PM) Menu Description ................................................................................................................. 56

5.9 Generate an External Pulse-Modulated Signal ........................................................................................................... 65

CHAPTER 6 SPECIAL MODES ............................................................................................................................................. 67

6.1 Use Cable Correction ................................................................................................................................................... 68

6.2 Use External ALC ......................................................................................................................................................... 71

6.3 Use the External Reference Input ............................................................................................................................... 74

CHAPTER 7 SYSTEM MENUS ............................................................................................................................................. 75

7.1 System Menus Description ......................................................................................................................................... 75

7.2 Use the Ref Tune Function .......................................................................................................................................... 80

CHAPTER 8 LANGUAGE MENUS ......................................................................................................................................... 82

8.1 Language Menu Description ....................................................................................................................................... 82

CHAPTER 9 PERFORMANCE VERIFICATION ............................................................................................................................ 86

9.1 Specifications .............................................................................................................................................................. 86

9.2 Performance Verification Procedures ....................................................................................................................... 100

9.2.1 List of Performance Verification Procedures ..................................................................................................... 100

9.2.2 Datasheets ......................................................................................................................................................... 101

9.2.3 Test Equipment .................................................................................................................................................. 101

9.2.4 Frequency Range, Resolution, and Accuracy ..................................................................................................... 102

9.2.5 Spectral Purity .................................................................................................................................................... 103

9.2.6 Maximum Leveled Power .................................................................................................................................. 106

9.2.7 Level Accuracy .................................................................................................................................................... 108

9.2.8 Step Attenuator Level Accuracy ......................................................................................................................... 110

9.2.9 Amplitude Modulation Accuracy ....................................................................................................................... 113

9.2.10 Amplitude Modulation Bandwidth .................................................................................................................. 116

9.2.11 Frequency Modulation Accuracy - Low Rate ................................................................................................... 118

9.2.12 Frequency Modulation Accuracy - High Rate .................................................................................................. 121

9.2.13 Pulse Modulation: Rise and Fall Time .............................................................................................................. 123

9.2.14 Pulse Modulation: Pulse Power Level Accuracy .............................................................................................. 126

9.2.15 Pulse Modulation: Pulse On/Off Ratio ............................................................................................................. 128

APPENDIX A ACCESSORIES AND OPTIONS .......................................................................................................................... 130

A.1 2500B Accessory & Option List ................................................................................................................................. 130

APPENDIX B ERROR MESSAGES ....................................................................................................................................... 132

B.1 Start-up Error Messages ........................................................................................................................................... 132

B.2 NV RAM Messages .................................................................................................................................................... 134

B.3 Remote Error Messages ............................................................................................................................................ 135

Page vi Operation Manual, Part Number 34737, Rev C, June 30, 2011

Giga-tronics Series 2500B Microwave Signal Generators

List of Tables

Table 1: 2500B Serial Number Label ....................................................................................................................................... 4

Table 2: Receiving and Inspection of the 2500B ..................................................................................................................... 5

Table 3: 2500B AC Power and Fuse Specifications ................................................................................................................. 6

Table 4: Start-Up the 2500B .................................................................................................................................................... 7

Table 5: Reset the 2500B to Default Values............................................................................................................................ 8

Table 6: Replace the 2500B Line Fuse ..................................................................................................................................... 9

Table 7: Contacting Giga-tronics Customer Service .............................................................................................................. 10

Table 8: 2500B Front Panel ................................................................................................................................................... 12

Table 9: 2500B Display Description ....................................................................................................................................... 14

Table 10: Modify a Menu Parameter .................................................................................................................................... 17

Table 11: Change the Step Size of a Parameter .................................................................................................................... 18

Table 12: 2500B Rear Panel .................................................................................................................................................. 20

Table 13: CW Menu ............................................................................................................................................................... 23

Table 14: Generate a CW Signal ............................................................................................................................................ 24

Table 15: Ramp Menus ......................................................................................................................................................... 28

Table 16: Generate a Frequency Swept Signal ..................................................................................................................... 34

Table 17: Generate a Power Swept Signal ............................................................................................................................ 35

Table 18: AM Menus ............................................................................................................................................................. 37

Table 19: Generate an Internally Modulated AM Signal ...................................................................................................... 40

Table 20: Generate an Externally Modulated AM Signal ...................................................................................................... 42

Table 21: FM Menus ............................................................................................................................................................. 45

Table 22: Generate an Internally Modulated FM Signal ....................................................................................................... 50

Table 23: Generate an Externally Modulated FM Signal ...................................................................................................... 52

Table 24: Generate an Externally Phase Modulated Signal .................................................................................................. 54

Table 25: PM Menus ............................................................................................................................................................. 57

Table 26: Generate an Externally Pulse Modulated Signal ................................................................................................... 66

Table 27: Use Cable Correction ............................................................................................................................................. 69

Table 28: External ALC Using a Crystal (Diode) Detector ...................................................................................................... 72

Table 29: External ALC Using a Power Meter ....................................................................................................................... 73

Table 30: Use an External Frequency Reference .................................................................................................................. 74

Table 31: System Menus ....................................................................................................................................................... 76

Table 32: System Menu - Connectivity ................................................................................................................................. 77

Table 33: System Menu – Service Submenu ......................................................................................................................... 78

Table 34: System Menu –Ethernet Submenu ....................................................................................................................... 79

Table 35: Use the Ref Tune Feature ...................................................................................................................................... 81

Table 36: Language Menus ................................................................................................................................................... 83

Table 37: General Specifications ........................................................................................................................................... 86

Table 38: 2500B Series Model Frequency Ranges ................................................................................................................ 88

Table 39: Frequency Specifications ....................................................................................................................................... 88

Table 40: Frequency Bands ................................................................................................................................................... 89

Table 41: Spectral Purity ....................................................................................................................................................... 90

Table 42: General Power Specifications................................................................................................................................ 91

Table 43: Maximum Leveled Output Power in dBm - Standard ........................................................................................... 91

Operation Manual, Part Number 34737, Rev C, June 30, 2011 Page vii

Giga-tronics 2500B Series Microwave Signal Generators

Table 44: Maximum Leveled Output Power in dBm - Option 20 .......................................................................................... 92

Table 45: Minimum Leveled RF Output Power In dBm ......................................................................................................... 93

Table 46: RF Power level Accuracy in dB .............................................................................................................................. 93

Table 48: SSB Phase Noise - Option 28A ............................................................................................................................... 94

Table 49: SSB Phase Noise - Option 28B ............................................................................................................................... 94

Table 50: Frequency and Power Sweep ................................................................................................................................ 94

Table 51: Amplitude Modulation .......................................................................................................................................... 95

Table 52: Frequency Modulation .......................................................................................................................................... 95

Table 53: Phase Modulation ................................................................................................................................................. 96

Table 54: Pulse Modulation .................................................................................................................................................. 96

Table 55: List Mode ............................................................................................................................................................... 97

Table 56: External ALC .......................................................................................................................................................... 97

Table 57: Internal Modulation Generator............................................................................................................................. 98

Table 58: Remote Programming ........................................................................................................................................... 99

Table 59: List of Performance Verification Procedures ...................................................................................................... 100

Table 60: Equipment for 2500B Performance Verification ................................................................................................. 101

Table 61: Frequency Range, Resolution, and Accuracy ...................................................................................................... 102

Table 62: Datasheet 1: Frequency Range, Resolution, and Accuracy ................................................................................. 103

Table 63: Spectral Purity ..................................................................................................................................................... 104

Table 64: Datasheet 2: Spectral Purity ................................................................................................................................ 105

Table 65: Maximum Leveled Power .................................................................................................................................... 106

Table 66: Datasheet 3: Maximum Leveled Power .............................................................................................................. 107

Table 67: Level Accuracy ..................................................................................................................................................... 108

Table 68: Datasheet 4: Level Accuracy ............................................................................................................................... 109

Table 69: Step Attenuator Level Accuracy .......................................................................................................................... 111

Table 70: Datasheet 5: Step Attenuator Level Accuracy Test ............................................................................................. 112

Table 71: Amplitude Modulation Accuracy ........................................................................................................................ 114

Table 72: Datasheet 6: Amplitude Modulation Accuracy Test ........................................................................................... 115

Table 73: Amplitude Modulation Bandwidth ..................................................................................................................... 116

Table 74: Datasheet 7: Amplitude Modulation Bandwidth ................................................................................................ 117

Table 75: Frequency Modulation Accuracy - Low Rate....................................................................................................... 119

Table 76: Datasheet 8: FM Accuracy - Low Rate ................................................................................................................. 120

Table 77: Frequency Modulation Accuracy - High Rate ...................................................................................................... 121

Table 78: Datasheet 9: FM Accuracy - High Rate ................................................................................................................ 122

Table 79: Pulse Modulation: Rise and Fall Time ................................................................................................................. 124

Table 80: Datasheet 10: Pulse Modulation Rise and Fall Time Test ................................................................................... 125

Table 81: Pulse Modulation: Pulse Level Accuracy ............................................................................................................. 127

Table 82: Pulse Modulation: On/Off Ratio .......................................................................................................................... 129

Table 83: 2500B Add-on Accessories and Options ............................................................................................................. 130

Table 84: Start-up Error Messages ...................................................................................................................................... 133

Table 85: 2500B Remote Error Messages ........................................................................................................................... 135

Page viii Operation Manual, Part Number 34737, Rev C, June 30, 2011

Giga-tronics Series 2500B Microwave Signal Generators

List of Figures

Figure 1: 2500B Start Up ......................................................................................................................................................... 7

Figure 2: 2500B Fuse Holder ................................................................................................................................................... 9

Figure 3: 2520B Front Panel .................................................................................................................................................. 11

Figure 4: Functional Areas of the 2500B Display .................................................................................................................. 14

Figure 5: Structure of the 2500B Menus ............................................................................................................................... 16

Figure 6: 2500B Rear Panel ................................................................................................................................................... 19

Figure 7: CW Menu ............................................................................................................................................................... 22

Figure 8: Power Offset Example ............................................................................................................................................ 23

Figure 9: Ramp Main Menu .................................................................................................................................................. 27

Figure 10: Ramp Freq Start/Stop Sweep Menu .................................................................................................................... 28

Figure 11: Ramp Freq Center/Span Sweep Menu................................................................................................................. 29

Figure 12: Ramp Power Sweep Menu ................................................................................................................................... 30

Figure 13: Step Freq Sweep Menu ........................................................................................................................................ 31

Figure 14: Intensity Marker Menu ........................................................................................................................................ 32

Figure 15: Amplitude Marker Menu ..................................................................................................................................... 33

Figure 16: AM Main Menu and Submenus ........................................................................................................................... 36

Figure 17: AM External Menu ............................................................................................................................................... 37

Figure 18: AM Internal Waveform ........................................................................................................................................ 38

Figure 19: AM - Internal Noise Menu.................................................................................................................................... 39

Figure 20: FM Main Menu and Submenus ............................................................................................................................ 44

Figure 21: FM External Menu ................................................................................................................................................ 45

Figure 22: DC FM Menu ........................................................................................................................................................ 46

Figure 23: FM Internal Menu ................................................................................................................................................ 47

Figure 24: ΦM External Menu .............................................................................................................................................. 48

Figure 25: ΦM Internal Menu ............................................................................................................................................... 49

Figure 26: PM Main Menu and Submenus ........................................................................................................................... 56

Figure 27: PM External Menu ............................................................................................................................................... 57

Figure 28: PM Internal Continuous Menu ............................................................................................................................ 58

Figure 29: PM Internal Gated Menu ..................................................................................................................................... 59

Figure 30: PM Internal Triggered Menu ................................................................................................................................ 61

Figure 31: PM Burst Mode Menu .......................................................................................................................................... 63

Figure 32: PM Burst Mode Menu 2 ....................................................................................................................................... 64

Figure 33: Pulse Modulation Using an External Modulation Source .................................................................................... 65

Figure 34: 8650A/B Universal Power Meter; Front Panel Controls ...................................................................................... 69

Figure 35: Cable Connection Setup ....................................................................................................................................... 70

Figure 36: Setup for External ALC ......................................................................................................................................... 71

Figure 37: System Main Menu and Submenus ..................................................................................................................... 75

Figure 38: System Menu ....................................................................................................................................................... 76

Figure 39: Connectivity Menu ............................................................................................................................................... 77

Figure 40: Service Menu ....................................................................................................................................................... 78

Figure 41: Ethernet Menu ..................................................................................................................................................... 79

Figure 42: Reference Tune Setup .......................................................................................................................................... 80

Operation Manual, Part Number 34737, Rev C, June 30, 2011 Page ix

Giga-tronics 2500B Series Microwave Signal Generators

Figure 43: Ref Tune Input Circuit .......................................................................................................................................... 80

Figure 44: Language Menu 1 ................................................................................................................................................. 82

Figure 45: Language Menu 2 ................................................................................................................................................. 84

Figure 46: Language Menu 3 ................................................................................................................................................. 85

Figure 47: 2500B Mechanical Specifications ......................................................................................................................... 87

Figure 48: Setup; Frequency Range, Resolution, and Accuracy .......................................................................................... 102

Figure 49: Spectral Purity Test Setup .................................................................................................................................. 104

Figure 50: Power Specifications Test Setup ........................................................................................................................ 106

Figure 51: Step Attenuator Level Accuracy Test Setup ....................................................................................................... 110

Figure 52: Amplitude Modulation Accuracy and Bandwidth Test Setup ............................................................................ 113

Figure 53: Frequency Modulation Accuracy and Deviation Bandwidth Test Setup ........................................................... 118

Figure 54: Pulse Modulation Rise and Fall Time Test ......................................................................................................... 123

Figure 55: Pulse Modulation Level Accuracy Test Setup .................................................................................................... 126

Figure 56: Pulse Modulation On/Off Ratio Test Setup ....................................................................................................... 128

Figure 57: Checksum Test Failure Screen ........................................................................................................................... 134

Page x Operation Manual, Part Number 34737, Rev C, June 30, 2011

Giga-tronics 2500B Series Microwave Signal Generators Safety and Manual Conventions

WARNING

CAUTION

Chapter 1 Safety and Manual Conventions

1.1 Unsafe Operating Conditions

If you notice any of the following conditions while operating electronics equipment, IMMEDIATELY de-energize the equipment.

The instrument fails to operate normally, or operates erratically. The power cable, receptacle, or plug on the instrument is damaged The instrument causes electrical shock or operates at abnormally high temperature. A liquid or foreign substance falls into the instrument The instrument generates an abnormal sound, smell, smoke, or sparking light.

If any of the above conditions occurs, contact Giga-tronics to get the instrument repaired.

Continuing to operate the instrument with any of the above conditions could cause death or

serious damage to the instrument and any equipment connected to it.

1.2 Safety and Manual Conventions

This manual contains conventions regarding safety and equipment usage as described below.

1.3 Personal Safety Alert

WARNING: Indicates a hazardous situation, which, if not avoided, could result in death or serious injury.

1.4 Equipment Safety Alert

CAUTION: Indicates a situation that can damage or adversely affect the 2500B or associated equipment.

1.5 Notes

Notes are denoted and used as follows:

NOTE: Highlights or amplifies an essential operating or maintenance procedure, practice, condition or statement.

Operation Manual, Part Number 34737, Rev C, June 30, 2011 Page 1

Safety and Manual Conventions Giga-tronics 2500B Series Microwave Signal Generators

Preset

Local

RF ON

System

Menu Name

Soft Button

1.6 Graphic Symbols for Front Panel Buttons

(Refer to Figure 3 on page 11) Softkeys are adjacent to menu items that appear in the right-side area of the display. Pressing a softkey selects a menu

item, which makes the menu item modifiable, or opens a submenu. The menu items next to the softkeys are different for different menus, thus changing the function of the softkeys.

In this manual, softkeys are shown as: followed by the name of the softkey.

For example: Frequency, for setting the instrument frequency.

Menu Buttons are shown as: For example, the System Menu button is:

Other front panel buttons are shown graphically as: , , .

Step Up/Step Down buttons:

Rotary knob:

Page 2 Operation Manual, Part Number 34737, Rev C, June 30, 2011

Giga-tronics 2500B Series Microwave Signal Generators Introduction

Chapter 2 Introduction

2.1 Overview

This chapter describes the controls, inputs/outputs, indicators, and display of the 2500B.

NOTE: In this manual, the term “2500B” is used to refer to all models in the 2500B series. A specific model of 2500B is referred to when necessary.

2.2 Giga-tronics 2500B Microwave Signal Generator Summary

The Giga-tronics 2500B series of microwave generators are high-performance, flexible instruments ideal for research and development (R & D) and manufacturing environments.

Among the characteristics that make the 2500B series an excellent choice for a wide variety of applications are:

Frequency range from 100 kHz to 50 GHz (depending on model in series) Low phase noise High output power (Option 20) Fast switching of both frequency and power (Option 29) Fast switching in both list mode and under remote control Full suite of analog modulation All 2500B signal generators comply with MIL-PRF-28800F, Class 3

In addition, the following are standard features on all models in the 2500B series:

High stability time-base 10 MHz and 100 MHz reference input/output External ALC, digital ramp frequency and power sweep Pulse burst mode capability Automation Xpress Interface software Analog Sweep Emulation modes

NOTE: Complete technical data for all options for the 2500B series is located on page 130.

Operation Manual, Part Number 34737, Rev C, June 30, 2011 Page 3

Introduction Giga-tronics 2500B Series Microwave Signal Generators

2500B Serial Number Label

Descriptor

Type of Information

Code

This is a two-digit manufacturing code

Model

This is a four-number code formatted as 25XXB. There are six models, each with a different frequency range. See below.

Serial

This is a seven-digit serial number, and provides a unique identifier for each 2500B.

Opt

When options have been included in the 2500B, one or more two-digit numbers are listed on this line of the label. For more information about options, refer to page 130.

Model

Frequency Range

2502B

100 kHz to 2.5 GHz

2508B

2 GHz to 8 GHz

2520B

2 GHz to 20 GHz

2526B

2 GHz to 26.5 GHz

2540B

2 GHz to 40 GHz

2550B

2 GHz to 50 GHz

NOTE: The models shown above whose frequency ranges start at 2 GHz can be ordered with Option 18, which extends the frequency range down to 100 kHz.

2.3 Configuration Information

Specific information regarding each 2500B is included on the serial number label on the rear of the instrument. The information on this label is described below.

Table 1: 2500B Serial Number Label

2.3.1 Special Configurations

When the 2500B has been configured for user-specific application(s), supplemental pages are inserted in the front of the binder for this manual. Remove the indicated page(s) and replace it (them) with the furnished Special Configuration supplemental page(s).

If the “Opt.” line contains a three digit number (for example, 641), there is a combination of options and/or special modifications installed in the instrument. Information relating to these special configurations is contained in supplemental pages included with the manual.

Information about standard options starts on page 130.

Page 4 Operation Manual, Part Number 34737, Rev C, June 30, 2011

Giga-tronics 2500B Series Microwave Signal Generators Introduction

Receiving and Inspection of the 2500B

Step

Action

Before opening the shipping container, inspect it for any signs of damage. If THERE IS evidence of damage; record the location and extent of the damage and contact the

shipper immediately to report the damage. If there is NO EVIDENCE of damage; continue to the next step.

Open the shipping container and inspect the contents for evidence of damage. The contents should include any external, loose options and accessories, and the following:

Operation Manual USB 2.0 Type A Male to Type B Male cable

NOTE: This cable can be used to connect a computer to the 2500B for remote control and firmware upgrades.

Power cord, 6 feet Automation Express CD-ROM

NOTE: for complete information about Automation Xpress, refer to the 2500B Programming Manual, Part Number 34783.

If any of the contents are damaged or missing, contact Giga-tronics immediately. Refer to the Contact Information on page ii of this manual.

End of procedure

2.4 Receiving and Inspection

Follow the procedure in Table 2 for receiving and inspecting the 2500B.

Table 2: Receiving and Inspection of the 2500B

Operation Manual, Part Number 34737, Rev C, June 30, 2011 Page 5

Introduction Giga-tronics 2500B Series Microwave Signal Generators

2500B AC Power and Fuse Specifications

Parameter

Specification

AC line voltage

90 to 253 Volts. NOTE: The 2500B automatically adjusts to operate at

any voltage within the voltage range shown above. No adjustments are necessary.

AC line frequency

47 to 440 Hz

Internal fuse (in rear of 2500B)

3 A, Slow-Blow, 250V, Type T NOTE: The procedure for replacing the fuse is in

Table 6 on page 9.

2.5 Prepare the 2500B for Use

2.5.1 Cooling Considerations

The 2500B has an internal cooling fan. The air intake is located on the rear panel of the instrument. When placing or installing the instrument for use, ensure there are no obstructions to the flow of air into the instrument, nor obstruction for exhaust air flow at either side of the instrument.

2.5.2 AC Power Requirements

Table 3 below describes the power requirements and internal fuse specifications for the 2500B. AC Line Cord: All 2500B microwave signal generators are supplied with a 6-foot, three-wire power cord with three-

terminal polarized plug with a safety ground. If a different power cord is used, it must not exceed 3 meters (9 feet) in order to meet safety requirements.

Table 3: 2500B AC Power and Fuse Specifications

Page 6 Operation Manual, Part Number 34737, Rev C, June 30, 2011

Giga-tronics 2500B Series Microwave Signal Generators Introduction

Start-Up the 2500B

Step

Action

Place the 2500B in the location where it will be used, observing the recommendations in section

2.5 on page 6.

Plug the 2500B power cord into a suitable source of electrical power (see Table 3 on page 6 for electrical power specifications).

Press the power switch on the front panel of the 2500B. The 2500B displays the following sequence of screens:

“Initializing” momentarily appears on the display. The screen shown in Figure 1 appears.

The following information is displayed on the start-up screen:

The firmware version The serial number of the 2500B The Build Date (BD) or the firmware version The Build Time (BT) of the firmware version A progress bar at the bottom of the screen

Figure 1: 2500B Start Up

Upon the successful conclusion of start-up, the CW Menu is displayed.

If error messages occur during start-up: Refer to page 132.

End of Procedure

2.5.3 Start-up the 2500B

Table 4 below describes how to start-up the 2500B.

Table 4: Start-Up the 2500B

Operation Manual, Part Number 34737, Rev C, June 30, 2011 Page 7

Introduction Giga-tronics 2500B Series Microwave Signal Generators

Reset the 2500B to Default Values

Step

Action

Press the power switch on the front of the 2500B to de-energize the instrument. Wait 5 seconds, then go to the next step.

Push the power switch in to energize the unit. While the message “INITIALIZING” is displayed, press and hold the Preset button.

When the “Resetting Memory...” screen is displayed, release the PRESET button.

The system continues to power up normally. All information stored in the memory locations is cleared, and the system resets to factory default settings.

End of Procedure

2.5.4 Reset the 2500B to Factory-Default Values

The 2500B uses non-volatile memory (NVRAM), which is preserved with a battery for storing the instrument’s current state, saved setups, and lists. If you want to return these saved settings in NVRAM to the default values they were set to at the factory, perform the procedure below.

Table 5: Reset the 2500B to Default Values

Page 8 Operation Manual, Part Number 34737, Rev C, June 30, 2011

Giga-tronics 2500B Series Microwave Signal Generators Introduction

Replace the 2500B Line Fuse

Step

Action

Use the power switch on the front of the 2500B to switch the unit into STANDBY.

On the rear of the 2500B, disconnect the AC line cord. The fuse compartment is located to the left of the AC line cord socket.

Remove the fuse as follows (see Figure 2):

A) Use a small flat-blade screwdriver to pry open the fuse compartment. B) Pull out the white fuse holder. C) You can now remove the fuse from the fuse holder.

Figure 2: 2500B Fuse Holder

Replace the fuse with a new fuse (3 A, Slow-Blow, 250V, Type T).

Push the fuse holder in, and close the fuse compartment door.

Plug the AC line cord into the rear of the 2500B and return the instrument to operation. NOTE: If the 2500B continues to blow fuses, contact your local Giga-tronics sales representative

or the Giga-tronics factory. See the contact information on page ii of this manual.

End of Procedure

2.5.5 Replace the AC Line Fuse

If the AC line fuse in the 2500B continues to blow, it’s usually an indication of internal problems. If this occurs, contact

Giga-tronics for help (see Table 7 on page 10). Table 6 below describes how to replace the fuse in the 2500B.

Table 6: Replace the 2500B Line Fuse

Operation Manual, Part Number 34737, Rev C, June 30, 2011 Page 9

Introduction Giga-tronics 2500B Series Microwave Signal Generators

Contacting Giga-tronics Customer Service

repairs@gigatronics.com

Telephone (within the United States)

800.726.4442

Telephone

925.328.4669

Fax

925.328.4702

2.6 Shipping, Repair, and Calibration

2.6.1 Shipping the 2500B

If it is necessary to ship the 2500B, observe the following:

Use the best packaging materials available. If possible, reuse the original shipping container. If the original shipping container is not available, use a strong carton (350 lbs./sq. in. bursting strength) or a wooden

box.

Wrap the instrument in electro-static dissipative material before placing it into the shipping container. Completely fill the areas on all sides of the instrument with packaging material. Take extra precaution to protect the

front and rear panels.

Seal the package with strong tape or metal bands. Mark the outside of the package clearly, and in bold type, as

follows:

FRAGILE — DELICATE INSTRUMENT

2.6.2 Repairs

The Giga-tronics 2500B microwave signal generator is a robust instrument that has been designed and built for years of trouble-free service. However, if you experience problems with the instrument, do the following:

1. Contact your local Giga-tronics sales office, or the factory, and be prepared to provide the model, serial number,

and any included options of your instrument, and a description of the problem. To contact the factory directly, use the following information:

Table 7: Contacting Giga-tronics Customer Service

2. If it is has been determined that you must ship the 2500B to the factory or a service center for repair, you will be

issued a Return Materials Authorization (RMA) number. Use the RMA number in all correspondence regarding the repair.

3. Pack the 2500B for shipment as described in the previous section, and enclose all relevant information regarding

the problem.

4. Ship the 2500B to the address provided by Giga-tronics Customer Service.

2.6.3 Calibration

Giga-tronics recommends that the 2500B be calibrated every two years. For more information regarding calibration of your instrument, contact Giga-tronics (see page ii of this manual).

Page 10 Operation Manual, Part Number 34737, Rev C, June 30, 2011

Giga-tronics 2500B Series Microwave Signal Generators Introduction

2.7 2500B Front Panel

Figure 3, below, describes the main features of the front panel of the 2500B. Refer to the tables on the following pages for detailed descriptions of the parts of the front panel.

NOTE: A 2520B is shown in Figure 3. The 2520B front panel is representative of the entire 2500B series.

Figure 3: 2520B Front Panel

Operation Manual, Part Number 34737, Rev C, June 30, 2011 Page 11

Introduction Giga-tronics 2500B Series Microwave Signal Generators

2500B Front Panel

Name

Description

POWER button

Puts the 2500B into one of two states:

STANDBY; power is applied to the internal timebase oscillator. This is to maintain

timebase stability when the 2500B is not in use.

ON; all functions of the 2500B are available for use.

NOTE: To ensure specified performance, allow the 2500B to remain ON or in STANDBY for at least 30 minutes prior to using the instrument.

POWER indicator

BLUE indicates the instrument is ON and all functions are available. AMBER indicates the instrument is in STANDBY mode.

LOCAL button

If in REMOTE mode, pressing this button puts the instrument into LOCAL mode. If the unit is in LOCAL mode: pressing this button displays menus that allow you

to choose the remote command language used during remote operation.

PRESET button

Pressing the PRESET button momentarily presets instrument settings to factory

default values, but does not affect system memory locations, display contrast, or the GPIB address.

Pressing and holding the PRESET button while the unit is powering up initializes

NVRAM, which includes presetting instrument settings to factory default values as well as initializing all ten system memory locations, the display contrast, and the GPIB address.

Display

Displays current instrument settings, and menus for modifying the settings. The active display is the group of instrument settings and associated menu items

that are currently displayed.

Softkeys

Selects the menu items adjacent to them in the display for modification.

Numeric Keypad

Use for entering numeric settings for generator functions.

STEP SIZE button

Selects and allows editing of the step size by the Step Up/Step Down buttons, rotary knob, or numeric keypad. To change a step size, see Table 11 on page 18.

RF ON button

Activates RF power output from the 2500B.

Step up/down buttons

Increases or decreases the selected parameter in the display by the amount specified by the step size.

Rotary knob

Adjusts the parameter that is selected in the display. When a maximum or minimum limit is reached, a message appears at the bottom of the display.

Unleveled indicator

When this indicator illuminates, it means that the power output cannot be increased any further, even though the power output displayed on the front panel may show an increase. The unleveled point varies with frequency.

External Reference (Ext Ref) Indicator

Illuminated when the 2500B is operating with an external reference applied.

Table 8: 2500B Front Panel

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Giga-tronics 2500B Series Microwave Signal Generators Introduction

2500B Front Panel

Name

Description

RF On/Off Indicator

This indicator has two states:

BLUE indicates the 2500B RF output is active. NOT illuminated indicates the RF output is not active.

RF Output

The connector type of the RF Output is determined by the upper frequency limit of the instrument, as follows:

2502B and 2508B: type-N (F) 2520B: SMA (F) 2526B: SMA (F) 2540B: 2.92 mm (F) 2550B: 2.4 mm (F)

NOTE: On some options, the RF output is on the rear panel. Refer to page 130 for information about all options.

Menu buttons

CW Button

Press this button to display the CW Menu. Shows parameters related to the CW functions and the Cable Correction functions and their associated menu items.

RAMP Button

Press this button to display either the Ramp Frequency or Ramp Power Menus.

SYSTEM Button

Press this button to display either the System 1 or System 2 menu.

AM Button

Press this button to display the Amplitude Modulation (AM) menus.

FM Button (Includes phase

modulation menus)

Press this button to display the Frequency Modulation (FM) and Phase Modulation (ΦM) menus.

PM Button

Press this button to display the Pulse Modulation (PM) menu.

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Introduction Giga-tronics 2500B Series Microwave Signal Generators

2500B Display Description

Area of Display

Description

Menu Name

Name of the menu that is displayed. This is called the active menu.

Parameters

Displays the current values of the instrument settings associated with the active menu. Parameters can be modified by the rotary knob or Step Up/Down buttons.

Step Size/Messages

The step size is the minimum increment by which a parameter can be modified. The step size can be adjusted. Non-error user messages can also appear in this area.

Menu Area

Displays one of the following:

Submenus Menu items that can be modified in the active menu.

Menu items are selected (made active) by pressing the adjacent softkey. The row containing the active parameter has a bold border around it.

Softkeys

Each softkey makes a submenu selectable or parameter active for modification.

2.7.1 Menus

Menus appear on the front panel display of the 2500B. The figure below shows the CW menu to illustrate the common areas of all menus.

Figure 4: Functional Areas of the 2500B Display

Table 9: 2500B Display Description

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Giga-tronics 2500B Series Microwave Signal Generators Introduction

2500B Display Description

Area of Display

Description

Mode

This area may contain one of the following codes:

OFS appears if a power offset greater than 0 dB is set in the CW menu. SLP appears if a power slope greater than 0 dB/GHz is set in the CW menu. AM appears if internal or external amplitude modulation is enabled FM appears if internal or external frequency modulation is enabled ΦM appears if internal or external phase modulation is enabled PM appears if internal or external pulse modulation is enabled EXT LEVEL appears if ALC is set to external UNLK appears if the Phase Lock Loop is unlocked

OVEN COLD appears if the internal temperature of the 2500B has not reached operational temperature. It is not recommended to use the 2500B while this indicator is active.

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Introduction Giga-tronics 2500B Series Microwave Signal Generators

AM Ext Menu

Page 37

AM Int Noise Menu

Page 39

AM Int Menu

Page 38

CW MENU

Page 22

FM Ext Menu

Page 45

DC FM Menu

Page 46

FM Int Menu

Page 47

ΦM Ext Menu

Page 48

ΦM Int Menu

Page 49

PM Int Cont Menu

Page 58

PM Int Gated Menu

Page 59

PM Trig Menu

Page 61

PM Burst Menu

Page 63

PM Ext Menu

Page 57

Language Menu 1

Page 83

Language Menu 2

Page 84

Language Menu 3

Page 85

LOCAL

RAMP

Intensity Marker Menu

Page 32

Ramp Freq Start/Stop Sweep Menu

Page 28

Ramp Freq Center/Span Sweep Menu

Page 29

Amplitude Marker Menu

Page 33

SYSTEM

Connectivity Menu

Page 77

Service Menu

Page 78

System Menu

Page 75

Ramp Power Sweep Menu

Page 30

Step Freq Sweep Menu

Page 31

Ethernet Menu

Page 79

2.7.2 Menu Structure

Figure 5 below shows the structure of the menus of the 2500B. To access the menus, you must first press one of the blue Menu buttons (see Figure 3 on page 11).

Page 16 Operation Manual, Part Number 34737, Rev C, June 30, 2011

Figure 5: Structure of the 2500B Menus

Giga-tronics 2500B Series Microwave Signal Generators Introduction

Modify a Menu Parameter

Step

Action

Press the softkey adjacent to the parameter you want to modify. Note that the parameter becomes enclosed in a bold outline box when it is selected.

Modify the value of the parameter by using , , or the numeric keypad (except where otherwise noted).

End of Procedure

2.7.3 Access the Menus

In local operation, the 2500B menus are accessed via the Menu buttons or Local button on the front panel (see

Figure 3 on page 11). Pressing a Menu button causes the menu for that button to appear on the display. The Menu buttons are:

o CW o Ramp o System o AM o FM; includes phase modulation (ΦM) menus o PM

The LOCAL button allows you to access and modify communication functions during remote operation of the 2500B

(see Figure 3 on page 11).

2.7.4 Softkeys

Use the softkeys (see Figure 4 on page 14) to select a submenu or parameter shown to the left of the softkey, in the display.

Pressing a softkey next to a submenu displays the submenu and makes its parameters available for viewing and

modification.

Pressing a softkey next to a parameter makes it active for modification.

2.7.5 Modify Menu Parameters

Parameters in the Menu Area of the display (see Figure 4 on page 14) can be modified using either the rotary knob, Step Up/Down keys, or the numeric keypad (see Figure 3 on page 11), except where otherwise noted. Table 10 below describes how to modify a menu parameter.

Table 10: Modify a Menu Parameter

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Introduction Giga-tronics 2500B Series Microwave Signal Generators

Change the Step Size of a Parameter

Step

Action

Use a softkey to select a parameter. For example, in the CW menu, select Frequency.

Press the Step Size button (see Figure 3 on page 11).

Enter a new step size using the numeric keypad.

Press the appropriate Units button (see Figure 3 on page 11).

Press the Step Size button to save the new step size. Now, when you change the CW frequency using the Step Up/Step Down buttons or the rotary knob, the parameter changes according to the new Step Size.

End of Procedure

2.7.6 Modify the Step Size

The step size for a parameter can be modified as described below.

Table 11: Change the Step Size of a Parameter

Page 18 Operation Manual, Part Number 34737, Rev C, June 30, 2011

Giga-tronics 2500B Series Microwave Signal Generators Introduction

2.8 2500B Rear Panel

Figure 6 below shows the locations of the components on the 2500B rear panel. Descriptions of the rear panel components are on the following pages.

Figure 6: 2500B Rear Panel

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Introduction Giga-tronics 2500B Series Microwave Signal Generators

2500B Rear Panel

Name

Description

EXT ALC

In external leveling, the RF output of the 2500B is detected by either a positive or negative crystal detector, or power meter with an analog output. The signals from these devices are connected to the ALC circuitry of the 2500B, which is used to compensate for standing wave effects or cable and component losses at the input of the device under test.

MODULATION GENERATOR

FM/φΜ OUT

The internal modulation generator output; 2 Vpp into 10 kΩ.

PULSE OUT

A +4 V video representation of the pulsed RF output signal.

AM OUT

The internal modulation generator output; 2 Vp-p into 10 kΩ.

PM SYNC OUT

A synchronization output pulse of > 75 ns width, TTL levels that can be delayed relative to the leading edge of the video signal at the PULSE OUT connector.

Limits of delay: ≥ 50 ns, ≤ 10 ms.

FM/φM IN

A 50 Ω input for an external FM or φM modulating signal. The input signal can be

any waveform compatible with bandwidth considerations. A 1-V peak input produces maximum deviation. Maximum input is ± 1 V p-p.

An externally supplied DC signal can be applied to this input to modulate the

frequency of the CW output.

AM IN

A 600 Ω input for an external AM signal. The input signal can be any waveform compatible with bandwidth considerations. Maximum input is ± 1 V p-p.

PULSE IN PM TRIG IN

A Pulse Modulation Input for external Pulse In. The input parameters are: TTL, polarity selectable, 50 Ω characteristic impedance, 2 kΩ pull-up.

LOCK/LEVEL

+5 Volt output, active high when the 2500B is phase locked and output leveled. The Lock and Level indicator is valid for CW and List mode.

REF TUNE

A 0 to +10 Volts, high-impedance input for tuning the internal reference in order to adjust the output frequency approximately +5 ppm. Do not exceed +15 Volts or apply a negative voltage greater than -1 Volt.

SYNC OUT

In List mode, the unit can be set to generate a pulse at this output when a specified list point is reached. The RF output can be delayed from the start of the list point up to a maximum of 10 ms. The pulse width of the SYNC OUT signal is determined as follows:

Pulse width = Step Time - Sync Delay - 10 µs.

In Ramp operation, the pulse occurs at the start of each ramp sweep. In either case, the output pulse is +5 Volts.

TRIGGER IN

Triggers a List. Accepts a TTL level signal of > 50 ns width.

Table 12: 2500B Rear Panel

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Giga-tronics 2500B Series Microwave Signal Generators Introduction

2500B Rear Panel

Name

Description

NETWORK ANALYZER

BLANKING

A +5 Volt output signal occurring at band crossings, filter switches, and retraces for the duration of those events.

RAMP OUT

A 0 to 10 Volt ramp output scaled to the frequency sweep.

STOP SWP IN/OUT

Stop Sweep I/O is a 5 Volt, 2 kΩ, active-low signal that temporarily interrupts the instrument’s frequency or power ramp sweep. This feature is only available with HP8340 or HP8370 command emulation.

V/GHz

An output voltage that is directly proportional to output frequency. The output is 0.5 Volts per GHz.

100 MHz OUT

> +5 dBm, AC coupled, 100 MHz low-noise reference output signal into 50 Ω.

10 MHz OUT

10 MHz TTL reference output signal into 50 Ω.

EXT REF IN

The external reference input. Can be either a 10 MHz input that is > -5.0 dBm into 50 Ω or a 100 MHz input > +5 dBm. The 100 MHz input level should not exceed +8 dBm for best performance.

NOTE: If the external frequency reference has excessive noise or drift, this will degrade the performance of the 2500B.

GPIB

A 24-pin IEEE STD 488.2 connector for control of the instrument during remote operation using GPIB.

RS-232

A DB-9 connector for control of the instrument during remote operation using RS-232 serial communications.

USB

A USB connector for control of the instrument during remote operation using USB 2.0 (full speed) communications

Ethernet

An Ethernet connector for control of the instrument during remote operation using LAN interface communications.

AC Power Input

90 to 253 V ac, auto-sensing, 47 Hz to 440 Hz.

NOTE: All rear panel I/O connectors (except the GPIB, RS-232, LAN, USB, and AC power connections) are type BNC unless otherwise stated. Some connectors may be inactive due to installed options.

Operation Manual, Part Number 34737, Rev C, June 30, 2011 Page 21

CW Operation Giga-tronics 2500B Series Microwave Signal Generators

Chapter 3 CW Operation

This section describes the CW Menu of the 2500B, and includes an example procedure for generating a CW signal.

The CW specifications of the 2500B start on page 86.

3.1 CW Menu Description

Figure 7: CW Menu

Page 22 Operation Manual, Part Number 34737, Rev C, June 30, 2011

Giga-tronics 2500B Series Microwave Signal Generators CW Operation

CW Menu

Parameter

Description

Frequency

The instrument’s center frequency. The range of the center frequency is dependent on the model number and options of the instrument.

Power

The output power level of the selected frequency. The range of the output power level also depends on the Power Offset and Power Slope settings in the CW menu, as well as other settings of the instrument.

Power Offset

The Power Offset feature increases the instrument’s output power by the amount of the Power Offset setting, without changing the Power level as shown in the display. This allows you to compensate for the insertion or conversion loss of components that are attached to the instrument’s RF output. An example is shown in Figure 8.

Figure 8: Power Offset Example

The Power Offset indicator (OFS) appears in the upper right-hand corner of the display when any power offset value greater than 0.00 dB is entered.

Power Slope

The power slope feature increases the instrument’s output power linearly as a function of the output frequency. The power slope function allows you to automatically compensate

for insertion/conversion losses of components attached to the instrument’s RF output that

exhibit a linear loss characteristic with frequency. The Power Slope indicator (SLP) appears in the upper right-hand corner of the display when the power slope is greater than 0.00 dB/GHz.

Phase Adjust

This menu item displays and allows you to modify the phase of the output signal. Note the following:

The phase of the signal is maintained until the phase is readjusted or whenever the

instrument frequency setting is changed.

When the instrument frequency setting is changed, the phase adjust setting is reset to

0 degrees.

Phase Adjust is specified for a minimum frequency range of 500 MHz to the maximum

frequency range of the instrument. Phase adjust is available for frequencies below 500 MHz, however the output response time of the phase adjust is decreased.

Table 13: CW Menu

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CW Operation Giga-tronics 2500B Series Microwave Signal Generators

Generate a CW Signal

Step

Action

Press .

Select Frequency. Enter the 1.250 GHz using the numeric keypad, , or . NOTE: Whenever the frequency of the instrument is changed, the Phase Adjust setting resets to 0

degrees. The Phase Adjust range is 500 MHz to the maximum frequency of the instrument.

If the step attenuator option IS INSTALLED in the unit: Go to the Step 4. If the step attenuator option IS NOT installed in the unit: Go to Step 5.

Softkey

3.2 Generate a CW Signal

This procedure describes how to setup the 2500B to generate a CW signal with the following characteristics:

Frequency: 1.250 GHz Power: 1 dBm Power offset: adjust as necessary to compensate for losses in test setup Power slope: adjust as necessary to compensate for losses that vary linearly with frequency Phase adjust: adjust as necessary

NOTE: The example procedure below uses specific parameters to illustrate how to setup the 2500B. You can use this procedure for real-life situations by simply changing the parameters to fit your needs.

Use this setup where a single, un-modulated frequency is needed, and where losses and frequency response are not significant in the cables and fixtures connecting to the DUT.

This procedure describes how to set up the 2500B to generate a continuous wave (CW) signal at a specified output power level. This procedure is also used to configure the carrier signal when modulation is used.

Table 14: Generate a CW Signal

Page 24 Operation Manual, Part Number 34737, Rev C, June 30, 2011

Giga-tronics 2500B Series Microwave Signal Generators CW Operation

Generate a CW Signal

Step

Action

The step attenuator, if installed, can be set to one of two modes:

Auto Mode: In this mode, the step attenuator automatically switches attenuation state as the

instrument’s output power level setting is varied. To set the step attenuator so that it automatically switches attenuation levels with changes in output power level;

1. Press .

2. Select System Menu.

3. Select Attenuation.

4. Use or Attenuation to select Auto.

Fixed Mode: In this mode, the step attenuator is set to a fixed level of attenuation. The

maximum and minimum settable range is +25 dB to -20 dB relative to the attenuator setting. To set the step attenuator so that it remains fixed at a desired level of attenuation

1. Press .

2. Select System Menu.

3. Select Attenuation.

4. Use , or Attenuation to select the level of attenuation.

Return to the main CW menu if necessary by pressing .

Select Power, and enter 1.00 dBm:

1. On the numeric keypad (see Figure 3 on page 11), enter 1.00.

2. Press the GHz/nSec/dBm units button

NOTE: You can also change the value by using the keys, or .

NEXT STEP: The insertion/conversion loss compensation features of the 2500B includes the:

Power Offset feature, which is used to compensate for a fixed level of insertion or conversion loss; Power Slope feature, which is used to compensate for insertion or conversion loss that linearly varies with

frequency.

If YOU WANT to use the insertion/conversion loss compensation features of the 2500B: Perform either, or both, Step 8 and Step 9 as necessary.

If you DO NOT want to use the insertion/conversion loss compensation features of the 2500B:

Go to Step 10.

To compensate for a fixed level of loss;

1. Select Power Offset.

2. Enter the desired loss correction using the numeric keypad, , or . Note that when a

correction factor is entered, OFS appears in the upper right corner of the display.

Softkey

System

Softkey

System

Operation Manual, Part Number 34737, Rev C, June 30, 2011 Page 25

CW Operation Giga-tronics 2500B Series Microwave Signal Generators

Generate a CW Signal

Step

Action

To compensate for a loss that varies linearly with frequency;

1. Select Power Slope.

2. Enter the desired correction factor using the numeric keypad, keys, or . Note that when

this correction factor is entered, SLP appears in the upper right corner of the display.

10.

To adjust the phase of the output; select Phase Adjust, and enter the desired phase shift using the numeric keypad, keys, or .

11.

If the RF ON indicator is not lit, press the RF ON button to enable the RF output.

12.

Verify that the Unleveled indicator is not lit.

13.

If the Unleveled indicator is lit, then the combination of output power level, power offset, power slope, and step attenuator mode (if applicable) is set inappropriately, and the RF output is unleveled. Adjust the combination of settings until the Unleveled indicator turns off.

End of Procedure

Softkey

Page 26 Operation Manual, Part Number 34737, Rev C, June 30, 2011

Giga-tronics 2500B Series Microwave Signal Generators Ramp Operation

Chapter 4 Ramp Operation

This chapter describes in detail the menus and parameters in the Ramp Menus. This chapter includes example procedures for using the 2500B front panel controls to setup ramps.

4.1 Ramp Menu Description

The Ramp Menu provides a powerful, flexible suite of functions to meet the most demanding test requirements. The figure below shows the Ramp Main Menu.

Ramps can be set up for frequency or power. When a ramp is created, one parameter is swept (either frequency or power), and the other parameter is held constant.

For example, if a frequency ramp is created, the power is held constant over the range of ramp frequencies. Conversely, if a power ramp is created, the frequency is held constant over the range of power.

Figure 9: Ramp Main Menu

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Ramp Operation Giga-tronics 2500B Series Microwave Signal Generators

Ramp Menus

Submenu

Parameter

Figure 10: Ramp Freq Start/Stop Sweep Menu

Ramp Freq Start/Stop Sweep Menu (see Figure 10)

Start Frequency This is the starting frequency of the frequency sweep. The start

frequency must be less than the stop frequency. If the start frequency is set higher than the stop frequency, the stop frequency is automatically adjusted to the same value.

Stop Frequency This is the ending frequency of the frequency sweep. The stop

frequency must be greater than the start frequency. If it is set lower than the start frequency, the start frequency is automatically set to the same value.

Power The output power level during the frequency sweep. The range of the power

level depends on the next two menu items and other settings of the instrument. The power level is held constant during a frequency sweep.

Sweep Time This is the duration of a single sweep. Resolution The sweep resolution is the number of frequency steps to be included in

the frequency sweep.

The step resolution can be set to:

401, 801, or 1601, or Analog sweep

Use the step up/step down buttons or rotary knob to set the resolution; the numeric keypad cannot be used.

Table 15: Ramp Menus

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Giga-tronics 2500B Series Microwave Signal Generators Ramp Operation

Ramp Menus

Submenu

Parameter

Figure 11: Ramp Freq Center/Span Sweep Menu

Ramp Freq Center/Span Sweep Menu

(see Figure 11)

Center Freq The center frequency of the frequency span that is swept. Span This menu item displays and allows you to modify the frequency range of the

ramp (sweep). The span is centered on the Center frequency. Power The output power level during the center/span frequency sweep. The range of

the power level can be set to any valid power setting of the instrument.

Sweep Time This is the duration of one cycle of a frequency sweep. Resolution This is the number of frequency steps in the frequency sweep.

The resolution can be set to:

401, 801, or 1601, or Analog sweep.

Analog Sweep provides a number of smooth frequency segments across a frequency range as opposed to the Digital Sweep feature which is made up of individual frequency points, from 401/801/1601 discrete frequency points.

A single Analog Sweep is comprised of a number of smaller sweep segments. Analog sweeps are broken down into anywhere from 1 to 685 sweep segments. Each segment is a smooth frequency ramp. The segment size depends on the current operating band and the sweep speed. Breaking a sweep into smaller segments allows the instrument to correct for RF amplitude variations between segments. See figure below.

Use the step up/step down buttons or rotary knob to set the resolution; the numeric keypad cannot be used.

Operation Manual, Part Number 34737, Rev C, June 30, 2011 Page 29

Ramp Operation Giga-tronics 2500B Series Microwave Signal Generators

Ramp Menus

Submenu

Parameter

Figure 12: Ramp Power Sweep Menu

Ramp Power Sweep Menu

(see Figure 12)

This function sweeps the RF output power level linearly from a start power level to a stop power level in a set duration, then repeats the sweep. The power level can sweep from a lower to a higher power level, or in the reverse direction. The output frequency is held constant during a power sweep. The maximum settable range for ramp power sweep is 45 dB.

NOTE: As soon as the Ramp Power menu is chosen, the instrument calculates the ramp, and then begins sweeping the output power. The ramp is recalculated whenever a parameter is changed. During calculations, the following message is shown at the bottom of the display:

PREPARING SWEEP DATA...

When the calculations are complete and the output is actively sweeping, the following message is shown:

RAMP SWEEPING

Start Power This is the beginning power level of the power level sweep.

The range for the start power parameter is -20 dBm to +25 dBm if the step

attenuator option is not installed in the instrument.

If the step attenuator option is installed, the start power range is from 25 dB above

to 20 dB below the step attenuator setting.

Stop Power This is the ending power level of the sweep.

If the step attenuator option is installed, the stop power range is from 25 dB above

to 20 dB below the step attenuator setting chosen.

If the step attenuator option is not installed in the instrument, the range for the

stop power parameter is -20 dBm to +25 dBm.

Frequency This is the frequency that undergoes a power ramp. The range of adjustment of this parameter is dependent on the model number of the instrument. Sweep Time This is the amount of time that elapses for one cycle of a power level sweep to complete. Step size Power step size

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Giga-tronics 2500B Series Microwave Signal Generators Ramp Operation

Ramp Menus

Submenu

Parameter

Figure 13: Step Freq Sweep Menu

Step Freq Sweep Menu

(see Figure 13)

This menu allows you to view and modify settings for the frequency sweep feature. Note the following:

When this feature is used, the frequency of the RF output sweeps linearly from a

settable start frequency to a settable stop frequency, over a sweep time, then repeats the sweep.

The sweep occurs in a set number of equal increments, as determined by the

Resolution setting.

The output power is held at the same level during a frequency sweep.

NOTE: As soon as the Step Freq Sweep menu is chosen, the instrument calculates the ramp, and then begins sweeping the output frequency. The ramp is recalculated whenever a parameter is changed. During calculations, the following message is shown at the bottom of the display:

PREPARING SWEEPING DATA...

When the calculations are complete and the output is actively sweeping, the following message is shown:

RAMP SWEEPING Start Frequency This is the starting frequency of the frequency sweep. The start frequency must be less than the stop frequency. If the start frequency is set higher than the stop frequency, the stop frequency is automatically adjusted to the same value. Stop Frequency This is the ending frequency of the frequency sweep. The stop frequency must be greater than the start frequency. If it is set lower than the start frequency, the start frequency is automatically adjusted to the same value. Power The output power level during the frequency sweep. The range of the power level depends on the configuration and settings of the instrument.

Step Time The duration of the step. Step Size Frequency step size

Operation Manual, Part Number 34737, Rev C, June 30, 2011 Page 31

Ramp Operation Giga-tronics 2500B Series Microwave Signal Generators

Ramp Menus

Submenu

Parameter

Figure 14: Intensity Marker Menu

Intensity Marker Menu

(see Figure 14)

The Intensity Marker Menu allows you to view and modify settings related to the instrument’s Intensity Markers used in conjunction with the frequency sweep. Five intensity markers can be set.

Intensity Markers These five items allow you to set the frequency of the intensity markers using the numeric key pad. The marker is activated and deactivated by pressing the marker soft key.

Markers All On/Off This menu item allows you to toggle the states of all 5 markers in the Intensity Marker menu. Pressing the adjacent softkey toggles all marker states to be all on or all off.

Page 32 Operation Manual, Part Number 34737, Rev C, June 30, 2011

Giga-tronics 2500B Series Microwave Signal Generators Ramp Operation

Ramp Menus

Submenu

Parameter

Figure 15: Amplitude Marker Menu

Amplitude Markers Menu

(see Figure 15)

The Amplitude Marker Menu allows you to view and modify settings related to the instrument’s Amplitude Markers used in conjunction with the frequency sweep. Five amplitude markers can be set. AmplMrkr1 through AmplMrkr2 These 5 items allow you to set the frequency of the amplitude markers using the numeric key pad. The marker is activated and deactivated by pressing the adjacent amplitude marker soft key. Markers All On/Off This menu item allows you to toggle the states of all markers in the Amplitude Marker menu. Pressing the adjacent soft key toggles all marker states to be all on or all off.

Operation Manual, Part Number 34737, Rev C, June 30, 2011 Page 33

Ramp Operation Giga-tronics 2500B Series Microwave Signal Generators

Softkey

Generate a Frequency-Swept Signal

Step

Action

Press to display the Sweep Main menu.

Press RAMP FREQ Start/Stop Sweep menu.

Select Start Frequency, and enter 1.00 GHz using the numeric keypad (and Units buttons), , or .

Select Stop Frequency, and enter 2.00 GHz using the numeric keypad (and Units buttons), , or . NOTE: The ramp stop frequency must be set equal to or greater than the ramp start frequency.

Select Power and enter the 1.00 dBm using the numeric keypad (and Units buttons),

, or .

Select Sweep Time, and enter 1.00 seconds using the numeric keypad (and Units buttons), , or .

Resolution, and select 401 using .

Select NOTE: The resolution setting determines the number of discreet frequency steps that will be included

in the frequency ramp. Three resolutions are available: 401, 801, or 1601. Higher resolution settings will result in more steps and a finer resolution ramp.

If the RF ON indicator is not lit, press the RF ON button to enable the RF output. When the RF output is enabled, the RF ON indicator is illuminated blue.

End of Procedure

Softkey

RAMP

4.2 Generate a Frequency-Swept Signal

This procedure describes how to set up a signal at a constant power level that sweeps linearly from a start frequency to a stop frequency over a set duration, then repeats the sweep. The signal will be set up with the following characteristics:

Start frequency: 1.00 GHz Stop frequency: 2.00 GHz Power level: 1.00 dBm

NOTE: The example procedure in this section uses specific parameters to illustrate how to setup the 2500B. You can use this procedure for real-life situations by simply changing the parameters to fit your needs.

Table 16: Generate a Frequency Swept Signal

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Giga-tronics 2500B Series Microwave Signal Generators Ramp Operation

RAMP

Softkey

Generate a Power-Swept Signal

Step

Action

Press

to display the Sweep Main menu.

Select

Ramp Power Sweep Menu.

Select Start Power, and enter 0.00 dBm using the numeric keypad (and Units buttons),

, or .

If the step attenuator option IS INSTALLED in the unit; Go to Step 5. If the step attenuator option IS NOT installed in the unit; Go to Step 6.

Attenuation in the RAMP POWER menu, and use to select the desired

Select step attenuator level.

NOTE: The step attenuator cannot be set to auto-switch while in power sweep mode. Choose a step attenuator level so that the range of the power sweep will be within 25 dB above and 20 dB below the step attenuator level chosen.

Select Stop Power, and enter 5.00 dBm using the numeric keypad (and Units buttons) ,

, or .

NOTE: The ramp stop power level can be set equal to, greater than, or less than the ramp start power level.

Select Frequency, and enter 1.00 GHz using the numeric keypad (and Units buttons) ,

, or .

Select Sweep Time, and enter 5.00 seconds using the numeric keypad (and Units buttons), , or .

Select Step Size, and enter 0.10 dB using the numeric keypad (and Units buttons),

, or .

10.

If the RF ON indicator is not lit, press the RF ON button to enable the RF output. When the RF output is enabled, the RF ON indicator is illuminated blue.

End of Procedure

4.3 Generate a Power-Swept Signal

This procedure describes how to set up the 2500B to generate a signal at a constant frequency that sweeps linearly from a set start power level to a set stop power level over a set amount of time, and repeats the sweep. The signal will be setup with the following characteristics:

Start power: 0.00 dBm Stop power: 5.00 dBm Frequency: 1.00 GHz Sweep time: 5.00 second Step size: 0.10 dB

NOTE: The example procedure in this section uses specific parameters to illustrate how to set up the 2500B. You can use this procedure for real-life situations by simply changing the parameters to fit your needs.

Table 17: Generate a Power Swept Signal

Operation Manual, Part Number 34737, Rev C, June 30, 2011 Page 35

Modulation Operation Giga-tronics 2500B Series Microwave Signal Generators

Chapter 5 Modulation Operation

This section describes the modulation menus in the 2500B, and includes example procedures for setting up modulated test signals.

NOTE: This section only applies to instruments with Option 17A or Option 17B installed.

Option 17A: add internal and external modulation Option 17B: add external modulation

5.1 AM Menu Description

Press the AM Menu button to display the AM Main Menu. From here, you can go to one of three submenus. See Figure 16 below.

The following pages describe the AM menus and their parameters.

Figure 16: AM Main Menu and Submenus

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AM Menus

Submenu

Parameter

Figure 17: AM External Menu

AM Ext Menu

(see Figure 17)

The AM External Menu allows you to view and modify settings for external amplitude modulation mode. In this mode, the RF output signal is modulated according to the signal that is applied to the rear panel AM IN connector.

Parameters in this submenu that can be modified are: AM Enables or disables amplitude modulation. The active menu, that is, the menu

that is currently being displayed, determines the AM mode that is used. Pressing either the adjacent soft key or the Step Up or Step Down buttons toggle the AM state.

The AM indicator is displayed in the upper right-hand corner of the display when amplitude modulation is turned on.

Sensitivity Determines the percentage of modulation produced per Volt of input into the AM IN connector. The AM sensitivity can be modified using the numeric keypad, the step up/step down buttons, or the rotary knob. The AM sensitivity range is 0 to 95 %/Volt, and the step size can be set in the range of 0.10 to 47.5 %/Volt.

Table 18: AM Menus

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Modulation Operation Giga-tronics 2500B Series Microwave Signal Generators

AM Menus

Submenu

Parameter

Figure 18: AM Internal Waveform

AM Int Menu

(see Figure 18)

The AM Internal Waveform menu allows you to view and modify settings in which the modulating signal is an internally-generated sine, triangle, ramp, or square waveform (the signal at the AM IN connector is not used).

Parameters in this submenu are: AM Enables or disables amplitude modulation. The active menu (the menu that is

currently being displayed), determines the AM mode that is used. Pressing the adjacent softkey or the Step Up or Step Down buttons toggle the AM state.

Depth The amount of modulation of the carrier amplitude expressed as a percentage. The maximum depth adjustment available is 95 %.

Rate The frequency (rate) of the internal modulating signal. The frequency cannot be set above 100 kHz.

Waveform Allows you to choose the type of waveform used as the internal modulating signal. The available selections are Sine, Triangle (symmetrical triangle wave), Ramp (positive going ramp), or Square (50 % duty cycle square wave).

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AM Menus

Submenu

Parameter

Figure 19: AM - Internal Noise Menu

AM Int Noise Menu

(see Figure 19)

The AM - Internal Noise menu allows you to view and modify settings related to an internal amplitude modulation mode in which the modulating signal is an internallygenerated Gaussian noise source (the signal at the AM IN connector is not used).

AM Enables or disables amplitude modulation. The active menu, (the menu currently displayed), determines the AM mode that is used. Pressing the adjacent softkey or the Step Up or Step Down buttons toggles the AM state.

Depth This menu item allows you to view and modify the AM depth setting, which is the amount of modulation of the carrier amplitude expressed as a percentage.

Operation Manual, Part Number 34737, Rev C, June 30, 2011 Page 39

Modulation Operation Giga-tronics 2500B Series Microwave Signal Generators

Generate an Internally Modulated AM Signal

Step

Action

Verify that the RF output is NOT energized by checking the RF on/off indicator on the front of the 2500B (see Figure 3 on page 11). If the indicator is lit, press the button to

de-energize the RF output.

Connect the RF output on the 2500B as needed.

Press the menu button (see Figure 3 on page 11).

In the CW menu, select 1.00 GHz for the frequency of the AM signal:

1. Press Frequency.

2. On the numeric keypad on the front panel of the 2500B, enter 1.

3. Press the GHz Units button (next to the numeric keypad) to enter the new frequency.

NOTE: You can also use the keys and to change the frequency.

In the CW menu, select 1.00 dBm for the power level of the AM signal:

1. Press Power.

2. On the numeric keypad on the front panel of the 2500B, enter 1.

3. Press the GHz (nSec/dBm) Units button (next to the numeric keypad) to enter the new power

level. NOTE: You can also use the keys and to change the power level.

Press the menu button.

In the AM Main Menu, press AM Int Menu. This opens the AM — Internal Waveform submenu (see Figure 18 on page 38).

Soft Button

RF ON

5.2 Generate an Internally Modulated AM Signal

The procedure below describes how to generate an AM signal with the following characteristics:

Carrier frequency = 1.00 GHz Carrier power = 1.00 dBm Depth of AM modulation = 20 % Rate of AM modulation = 50 kHz Modulating waveform = sine wave

Table 19: Generate an Internally Modulated AM Signal

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Generate an Internally Modulated AM Signal

Step

Action

In the AM — Internal Waveform submenu, set the following parameters:

1. Turn on AM modulation; press AM.

2. Set the depth of AM modulation; press Depth.

a. Use the numeric keypad, keys, or to change the depth of AM modulation to 20

3. Set the rate of AM modulation; press Rate.

a. Use the numeric keypad, keys, or to change the rate of AM modulation to 50

kHz.

4. Set the type of waveform used for AM modulation as a sine wave; press Waveform

until Sine selected.

Press the button to energize the RF output of the 2500B.

End of Procedure

RF ON

Soft Button

5.3 Generate an Externally Modulated AM Signal

The procedure below describes how to generate an AM signal using an external modulation source. The AM signal is set up to have the following characteristics:

Carrier frequency = 1.00 GHz Carrier power = 1.00 dBm Depth of AM modulation = 50 %/V Rate of AM modulation = 50 kHz Modulating waveform = sine wave

Equipment and Materials

External AM modulation source (see specifications in Table 51 on page 95) Cables and connectors for connecting the AM modulation source to the 2500B Cables and connectors for connecting device to be tested to the 2500B RF Output

Operation Manual, Part Number 34737, Rev C, June 30, 2011 Page 41

Modulation Operation Giga-tronics 2500B Series Microwave Signal Generators

Generate an Externally Modulated AM Signal

Step

Action

Verify that the RF output is NOT energized by checking the RF on/off indicator on the front of the 2500B (see Figure 3 on page 11). If the indicator is lit, press the button to de-energize

the RF output.

Connect the RF output on the 2500B as needed.

On the rear of the 2500B, locate the AM IN connector (see Figure 6 on page 19).

Connect the external AM modulation source to the AM IN connector (see Table 51 on page 95 for specifications for the external AM signal).

Press the menu button.

In the CW menu, select 1.00 GHz for the frequency of the AM signal:

1. Press Frequency.

2. On the numeric keypad on the front panel of the 2500B, enter 1.

3. Press the GHz Units button (next to the numeric keypad) to enter the new frequency.

NOTE: You can also use the keys and to change the frequency.

In the CW menu, select 1 dBm for the power level of the AM signal:

1. Press Power.

2. On the numeric keypad on the front panel of the 2500B, enter 1.

3. Press the GHz (nSec/dBm) Units button (next to the numeric keypad) to enter the new power

level. NOTE: You can also use the keys and to change the power level.

Press to display the AM Main Menu (see Figure 16 on page 36).

Press AM Ext Menu.

10.

Press AM to switch AM mode ON.

11.

Press Sensitivity.

12.

Adjust the sensitivity to 50 %/Volt:

1. On the numeric keypad, enter 50.

2. Press the kHz/mSec/ % Units button (see Figure 3 on page 11).

NOTE: You can also set the sensitivity by the using the keys and .

13.

Set the external AM modulation source for the following output:

Frequency: 50 kHz Amplitude: 1 V peak (or 2 V peak-to-peak) Output waveform: sine wave

Soft Button

RF ON

Table 20: Generate an Externally Modulated AM Signal

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Generate an Externally Modulated AM Signal

Step

Action

14.

Energize the output of the external AM modulation source.

15.

Energize the RF output of the 2500B.

End of Procedure

Operation Manual, Part Number 34737, Rev C, June 30, 2011 Page 43

Modulation Operation Giga-tronics 2500B Series Microwave Signal Generators

5.4 FM Menu Description

Pressing the FM menu button displays the FM Main Menu. From here, you can choose from among five submenus for modifying parameters for frequency and phase modulation. See Figure 20.

The following pages describe the FM menu and submenus in detail. NOTE: The FM Menu includes phase modulation modes.

Figure 20: FM Main Menu and Submenus

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Giga-tronics 2500B Series Microwave Signal Generators Modulation Operation

FM Menus

Submenu

Parameter

Figure 21: FM External Menu

FM Ext Menu

(see Figure 21)

The FM External menu allows you to view and modify settings for external frequency modulation mode, which is used when the modulating signal is provided externally. In external FM mode, the RF output signal is modulated by the signal that is applied to the rear panel FM/φM IN connector.

Items in this submenu that can be modified are: FM Enables or disables frequency modulation. The active menu, (the menu currently

displayed), determines the FM mode that is used. Pressing the adjacent soft key or the Step Up or Step Down buttons toggles the FM state.

Sensitivity Determines how much the RF output deviates in frequency per Volt of signal at the rear panel FM/φM IN connector.

Table 21: FM Menus

Operation Manual, Part Number 34737, Rev C, June 30, 2011 Page 45

Modulation Operation Giga-tronics 2500B Series Microwave Signal Generators

FM Menus

Submenu

Parameter

Figure 22: DC FM Menu

DC FM Menu

(see Figure 22)

In DC FM mode, the RF output signal is modulated by an external signal that is applied to the rear panel FM/φM IN connector. Note the following:

DC FM is available on all models including models with option 17A. Frequency range for DC FM operation is 500 MHz to the maximum frequency of

the instrument with a fixed maximum deviation of 125 kHz.

DC FM operation is available for frequencies above 500 MHz; however,

maximum deviation is limited to the frequency band maximum deviation of the

output frequency. There is one settable item in this submenu: DC FM Enables or disables DC frequency modulation. The active menu, (the menu

currently displayed), determines the FM mode that is used. Pressing the adjacent soft key or the Step Up or Step Down buttons toggle the FM state.

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Giga-tronics 2500B Series Microwave Signal Generators Modulation Operation

FM Menus

Submenu

Parameter

Figure 23: FM Internal Menu

FM Int Menu

(see Figure 23)

Allows you to view and modify settings related to an internal frequency modulation mode in which the modulating signal is an internally-generated sine, triangle, ramp, or square waveform (the signal at the FM/φM IN connector is not used).

Settable menu items are: FM Switches FM Internal on and off. FM Internal is an internally driven modulation.

FM - Internal can only be activated or deactivated using the step up/step down buttons.

Deviation Determines how much (in Hertz) the RF output deviates in frequency when modulated by the internal source.

Rate The rate (frequency) of the internal modulating signal. Waveform Allows you to view and choose the type of waveform used as the internal

modulating signal. The available selections are Sine, Triangle (symmetrical triangle wave), Ramp (positive going ramp), or Square (50 % duty cycle square wave).

Operation Manual, Part Number 34737, Rev C, June 30, 2011 Page 47

Modulation Operation Giga-tronics 2500B Series Microwave Signal Generators

FM Menus

Submenu

Parameter

Figure 24: ΦM External Menu

ΦM Ext Menu

(see Figure 24)

The ΦM External menu allows you to view and modify settings for external phase

modulation mode, which is used when the modulating signal is provided externally. In external ΦM mode, the RF output signal is modulated by a signal that is applied to the rear panel FM/φM IN connector.

Items in this submenu that can be modified are: ΦM Enables or disables modulation. The active menu, (the menu that is currently

displayed), determines the ΦM mode that is used. Pressing either the adjacent softkey or the Step Up or Step Down buttons toggle the ΦM state.

Sensitivity Use to view and modify the external ΦM sensitivity setting, which determines how much the RF output phase deviates in radians per Volt of signal at the rear panel FM/φM IN connector.

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Giga-tronics 2500B Series Microwave Signal Generators Modulation Operation

FM Menus

Submenu

Parameter

Figure 25: ΦM Internal Menu

ΦM Int Menu

(see Figure 25)

The ΦM -Internal menu allows you to view and modify settings related to an internal phase modulation mode in which the modulating signal is an internally-generated sine, triangle, ramp, or square wave-form (the signal at the FM/φM IN connector is not used).

Items in this submenu that can be modified are: ΦM This menu item enables or disables internally-generated phase modulation. ΦM

- Internal can only be activated or deactivated using the Step Up/Step Down buttons.

Deviation Determines how much the RF output deviates in phase when modulated by the internal source.

Rate The frequency of the internal modulating signal. Waveform This menu item allows you to view and choose the type of waveform

used as the internal modulating signal. The available selections are Sine, Triangle (symmetrical triangle wave), Ramp (positive going ramp), or Square (50 % duty cycle square wave).

Operation Manual, Part Number 34737, Rev C, June 30, 2011 Page 49

Modulation Operation Giga-tronics 2500B Series Microwave Signal Generators

Generate an Internally Modulated FM Signal

Step

Action

Verify that the RF output is NOT energized by checking the RF on/off indicator on the front of the 2500B (see Figure 3 on page 11). If the indicator is lit, press the button to de-energize

the RF output.

Connect the RF output on the 2500B as needed.

Press the menu button.

In the CW menu, select 1.00 GHz for the frequency of the FM signal:

4. Press Frequency.

5. On the numeric keypad on the front panel of the 2500B, enter 1.

6. Press the GHz Units button (next to the numeric keypad) to enter the new frequency.

NOTE: You can also use the keys and to change the frequency.

In the CW menu, select 1.00 dBm for the power level of the FM signal:

1. Press Power.

2. On the numeric keypad on the front panel of the 2500B, enter 1.

3. Press the GHz (nSec/dBm) Units button (next to the numeric keypad) to enter the new power

level.

NOTE: You can also use the keys and to change the power level.

Press the Menu button. The FM Main Menu opens in the display.

In the FM Main Menu, press FM Int Menu. The FM — Internal Waveform menu opens (see Figure 23 on page 47).

Press FM to switch FM on.

Soft Button

RF ON

5.5 Generate an Internally Modulated FM Signal

The procedure below describes how to generate an internally-modulated FM signal with the following characteristics:

Carrier frequency = 1.00 GHz Carrier power = 1.00 dBm Deviation = 200 Hz Rate of FM modulation = 50 kHz Modulating waveform = sine wave

Equipment and Materials

Cables and connectors for connecting device to be tested to the 2500B RF Output

Table 22: Generate an Internally Modulated FM Signal

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Generate an Internally Modulated FM Signal

Step

Action

Press Deviation.

10.

Set the FM deviation to 200 Hz:

1. On the numeric keypad on the front panel of the 2500B, enter 200.

2. Press the Hz Units button (next to the numeric keypad) to enter the new frequency.

NOTE: You can also use the keys and to change the frequency.

11.

Press Rate.

12.

Set the FM rate (frequency of the modulating signal) 50.00 kHz:

1. On the numeric keypad on the front panel of the 2500B, enter 50.

2. Press the kHz Units button (next to the numeric keypad) to enter the new frequency.

NOTE: You can also use the keys and to change the frequency.

13.

Repeatedly press Waveform until Sine is displayed.

14.

Press the button to energize the RF output of the 2500B.

End of Procedure

RF ON

Soft Button

Operation Manual, Part Number 34737, Rev C, June 30, 2011 Page 51

Modulation Operation Giga-tronics 2500B Series Microwave Signal Generators

Generate an Externally Modulated FM Signal

Step

Action

Verify that the RF output is NOT energized by checking the RF on/off indicator on the front of the 2500B (see Figure 3 on page 11). If the indicator is lit, press the button to de-energize

the RF output.

Connect the RF output on the 2500B as needed.

On the rear of the 2500B, locate the FM/ΦM IN connector (see Figure 6 on page 19).

Connect the external FM modulation source to the FM/ΦM IN connector (see specifications in Table 52 on page 95).

Press the menu button.

In the CW menu, select 1.00 GHz for the frequency of the FM signal:

1. Press Frequency.

2. On the numeric keypad on the front panel of the 2500B, enter 1.

3. Press the GHz Units button (next to the numeric keypad) to enter the new frequency.

NOTE: You can also use the keys and to change the frequency.

In the CW menu, select 1.00 dBm for the power level of the FM signal:

1. Press Power.

2. On the numeric keypad on the front panel of the 2500B, enter 1.

3. Press the GHz (nSec/dBm) Units button (next to the numeric keypad) to enter the new power

level.

NOTE: You can also use the keys and to change the power level.

Soft Button

RF ON

5.6 Generate an Externally Modulated FM Signal

The procedure below describes how to generate an FM signal that uses an external FM modulation source connected to the 2500B. An FM signal is created with the following characteristics:

Carrier frequency = 1.00 GHz Carrier power = 1.00 dBm Deviation = 1.00 kHz Rate of FM modulation = 50 kHz Modulating waveform = sine wave

Equipment and Materials

External FM modulation source (see specifications in Table 52 on page 95) Cables and connectors for connecting the FM modulation source to the 2500B Cables and connectors for connecting device to be tested to the 2500B RF Output

Table 23: Generate an Externally Modulated FM Signal

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Giga-tronics 2500B Series Microwave Signal Generators Modulation Operation

Generate an Externally Modulated FM Signal

Step

Action

Press the Menu button. The FM Main Menu opens in the display.

In the FM Main Menu, press FM Ext Menu. The FM — External Waveform menu opens (see Figure 21 on page 45).

10.

Press FM to switch FM on.

11.

Press Sensitivity. Set the Sensitivity to 1.00 kHz per Volt as follows:

1. On the numeric keypad on the front panel of the 2500B, enter 1.

2. Press the kHz Units button (next to the numeric keypad) to enter the new power level.

NOTE: You can also use the keys and to change the power level.

12.

Setup the external FM modulation source as follows:

Frequency: 50 kHz Amplitude: 1.00 V peak (or 2 V peak-to-peak)

13.

Press the button to energize the RF output of the 2500B.

End of Procedure

RF ON

Soft Button

Operation Manual, Part Number 34737, Rev C, June 30, 2011 Page 53

Modulation Operation Giga-tronics 2500B Series Microwave Signal Generators

Generate an Externally Phase Modulated Signal

Step

Action

Verify that the RF output is NOT energized by checking the RF on/off indicator on the front of the 2500B (see Figure 3 on page 11). If the indicator is lit, press the button to de-energize

the RF output.

Connect the RF output on the 2500B as needed.

On the rear of the 2500B, locate the FM/ΦM IN connector (see Figure 6 on page 19).

Connect the external ΦM modulation source to the FM/ΦM IN connector.

Press the menu button.

In the CW menu, select 4.00 GHz for the frequency of the ΦM signal:

4. Press Frequency.

5. On the numeric keypad on the front panel of the 2500B, enter 4.

6. Press the GHz Units button (next to the numeric keypad) to enter the new frequency.

NOTE: You can also use the keys and to change the frequency.

In the CW menu, select 1 dBm for the power level of the ΦM signal:

4. Press Power.

5. On the numeric keypad on the front panel of the 2500B, enter 1.

6. Press the GHz (nSec/dBm) Units button (next to the numeric keypad) to enter the new power

level.

NOTE: You can also use the keys and to change the power level.

14.

Press the Menu button. The FM Main Menu opens in the display.

Soft Button

RF ON

5.7 Generate an Externally Phase Modulated Signal

The procedure in this section describes how to generate a phase-modulated (ΦM) signal from the 2500B using an external phase modulation source connected to the 2500B. The ΦM signal is set up to have the following characteristics:

Carrier frequency = 4.00 GHz Carrier power = 1.00 dBm Deviation = 1 rad Rate of phase modulation = 1 kHz Modulating waveform = sine wave

Equipment and Materials

External phase modulation source (see specifications in Table 52 on page 95) Cables and connectors for connecting the ΦM modulation source to the 2500B Cables and connectors for connecting the device to be tested to the 2500B RF Output

Table 24: Generate an Externally Phase Modulated Signal

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Giga-tronics 2500B Series Microwave Signal Generators Modulation Operation

Generate an Externally Phase Modulated Signal

Step

Action

15.

In the FM Main Menu, press ΦM Ext Menu. The ΦM — External Waveform menu opens (see Figure 21 on page 45).

16.

Press ΦM to switch ΦM on.

17.

Press Sensitivity. Set the Sensitivity to 1 radian per Volt as follows:

3. On the numeric keypad on the front panel of the 2500B, enter 1.

4. Press the Hz Units button (next to the numeric keypad) to enter the new phase deviation level.

NOTE: You can also use the keys and to change the phase deviation.

18.

Setup the external ΦM modulation source as follows:

Amplitude = 1 V peak (or 2 V peak-to-peak) Frequency = 1 kHz

19.

Press the button to energize the RF output of the 2500B.

End of Procedure

RF ON

Soft Button

Operation Manual, Part Number 34737, Rev C, June 30, 2011 Page 55

Modulation Operation Giga-tronics 2500B Series Microwave Signal Generators

5.8 Pulse Modulation (PM) Menu Description

Pressing the PM menu button provides access to the internal and external pulse modulation features of the instrument. Figure 26 illustrates the PM Main menu and five submenus.

The following pages describe the PM submenus in detail.

Figure 26: PM Main Menu and Submenus

Pressing the bottom-right softkey toggles the PM leveling Menu between two states:

Always on Off for pulse widths < 1µs (causes 1 ms cal pulse)

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Giga-tronics 2500B Series Microwave Signal Generators Modulation Operation

PM Menus

Submenu

Parameter

Figure 27: PM External Menu

PM Ext Menu

(see Figure 27)

The PM External menu allows you to view and modify settings for external pulse modulation mode, which is used when the modulating signal is provided externally. In external PM mode, the RF output signal is pulsed by the signal that is applied to the rear panel PULSE IN/PM TRIG IN connector. When the instrument does not include the internal modulation generator, this is the only PM mode that is available.

Items in this submenu that can be modified are: PM Turns pulse modulation on and off. Press the adjacent soft key or the Step Up or

Step Down buttons toggle the PM state. The PM indicator is displayed in the upper right-hand corner of the display when pulse modulation is turned on.

Input Polarity Input polarity determines the TTL level at the PULSE IN/PM TRIG IN connector that will produce an “on” condition at the RF output. The available selections are:

Active High Active Low

Table 25: PM Menus

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Modulation Operation Giga-tronics 2500B Series Microwave Signal Generators

PM Menus

Submenu

Parameter

Figure 28: PM Internal Continuous Menu

PM Int Cont Menu

(see Figure 28)

The PM Internal Continuous menu produces a continuous pulse-modulated RF output with pulse characteristics determined by an internally-generated pulse signal (any signal at the PULSE IN/PM TRIG IN connector is ignored).

Items in this submenu that can be modified are: PM Turns pulse modulation on and off. Press the adjacent soft key or the Step Up or

Step Down buttons toggle the PM state. The PM indicator is displayed in the upper right-hand corner of the display when pulse modulation is turned on.

PRI The pulse repetition interval (PRI) of the internal pulse modulating signal. PRI sets the duration between similar edges of the modulating signal, and thus, the RF output’s pulse repetition interval. The frequency of the pulses is the reciprocal of the PRI; frequency = 1/PRI.

NOTE: This parameter setting is used for the internal continuous and internal gated pulse modulation modes; it is not set and stored separately for those modes.

Width: The width of the internal pulse modulating signal. Sets the duration of the longest state of the internal modulating signal and the RF output’s pulse width.

NOTE: This parameter setting is used for all three internal pulse modulation modes (continuous, triggered, and gated); it is not set and stored separately for each of these modes.

Sync Out Delay Sets the amount of delay that occurs between the leading edge of the video pulse at the PULSE OUT connector and the leading edge of the sync pulse at the PM SYNC OUT connector.

NOTE: This parameter setting is used for all three internal pulse modulation modes (continuous, triggered, and gated); it is not set and stored separately for each of these modes.

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Giga-tronics 2500B Series Microwave Signal Generators Modulation Operation

PM Menus

Submenu

Parameter

Figure 29: PM Internal Gated Menu

PM Int Gated Menu

(see Figure 29)

The PM Internal Gated menu allows you to view and modify the internal gated pulse

modulation mode. In this mode, the instrument’s CW signal is pulse modulated

according to the PRI and Width settings of its internal pulse modulation generator, but appears at the RF output connector as determined by the gating signal that is applied to the rear-panel PULSE IN/PM TRIG IN connector.

PM Turns pulse modulation on and off. Pressing the adjacent soft key or the Step Up or Step Down buttons toggles the PM state. The PM indicator is displayed in the upper right-hand corner of the display when pulse modulation is turned on

NOTE: This parameter setting is used for the internal continuous and internal gated pulse modulation modes; it is not set and stored separately for these modes.

Width Sets the duration of the longest state of the modulating signal pulses, and thus, the width of the pulses that appear at the RF output connector when an appropriate gating signal is applied to the rear-panel PULSE IN/PM TRIG IN connector.

If the width parameter is set to a value that is more than the current PRI setting,

the PRI setting is automatically adjusted to be 20 ns greater than the Width

setting. The step size can be set in the range of 10 ns to 5 ms. NOTE: The same width parameter setting gets used for all three internal pulse

modulation modes (continuous, triggered, and gated); it is not set and stored separately for each of these modes.

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Modulation Operation Giga-tronics 2500B Series Microwave Signal Generators

PM Menus

Submenu

Parameter

PM Int Gated Menu, continued

(see Figure 29)

Synch Out Delay Determines the amount of delay that occurs between the leading edge of the pulse video and the leading edge of the sync pulse at the PM SYNC OUT connector.

NOTE: The same sync out delay parameter setting gets used for all three internal pulse modulation modes (continuous, triggered, and gated); it is not set and stored separately for each of these modes.

Trigger In Determines the polarity of the TTL level at the PULSE IN/PM TRIG IN connector that is the active gating condition for a pulse modulated RF output. The available selections are as follows:

Active High Active Low

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PM Menus

Submenu

Parameter

Figure 30: PM Internal Triggered Menu

PM Int Trig Menu

(see Figure 30)

The PM Internal Triggered menu allows you to view and modify settings for internal triggered pulse modulation mode. In this mode, the instrument produces a single RF pulse at the RF output connector whenever it receives a valid trigger signal at the rearpanel PULSE IN/PM TRIG IN connector. The RF pulse thus generated has a width that is determined by the Width setting in this menu, and is delayed by the amount of delay set with the RF Pulse Delay setting in this menu.

Settable items in this submenu are: PM This menu item turns pulse modulation on and off. Pressing either the adjacent

softkey or the Step Up or Step Down buttons toggle the PM state. The PM indicator is displayed in the upper right-hand corner of the display when pulse modulation is turned on.

RF Pulse Delay Determines the amount of delay that occurs between the chosen triggering edge (rising or falling) of the signal at the PULSE IN/PM TRIG IN connector and the rising edge of the video pulse at the rear-panel PULSE OUT connector.

NOTE: The pulse that subsequently appears at the RF output connector is typically delayed by approximately 50 ns.

The RF pulse delay parameter can be modified using the numeric keypad, the step up/step down buttons, or the rotary knob.

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Modulation Operation Giga-tronics 2500B Series Microwave Signal Generators

PM Menus

Submenu

Parameter

PM Int Trig Menu, Continued

(see Figure 30)

Width This menu item allows you to view and modify the width of the pulse that appears at the RF out-put connector when an appropriate triggering signal is applied to the rear-panel PULSE IN/PM TRIG IN connector.

NOTE: The same width parameter setting gets used for all three internal pulse modulation modes (continuous, triggered, and gated); it is not set and stored separately for each of these modes.

Sync Out Delay Determines the amount of delay that occurs between the leading edge of the video pulse at the PULSE OUT connector and the leading edge of the sync pulse at the PM SYNC OUT connector.

Trigger Polarity Allows you to view and choose the edge of the TTL pulsed input signal applied to the PULSE IN/PM TRIG IN connector that is used to trigger an RF pulse at the RF output connector. Determines whether the rising edge or falling edge of the pulse at the PULSE IN/ PM TRIG IN connector will trigger an RF pulse at the output. The available selections are:

Rising Edge Falling Edge

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Giga-tronics 2500B Series Microwave Signal Generators Modulation Operation

PM Menus

Submenu

Parameter

Figure 31: PM Burst Mode Menu

PM Burst Menu

(see Figure 31)

PM This menu item turns pulse modulation on and off. Pressing the adjacent softkey or the Step Up or Step Down buttons toggles the PM state. The PM indicator appears in the upper right-hand corner of the display when pulse modulation is turned on.

PRI The pulse repetition interval (PRI) of the instrument’s internal pulse modulating signal. The PRI parameter sets the duration between similar edges of the modulating signal, and thus, the pulse repetition interval of the individual pulses within the pulse burst RF output. Range is 200 ns to 1 s. Each pulse in the pulse burst will have the same PRI. Note that the PRI must be equal or greater than the pulse width plus 20 ns.

Width The width of each pulse in a burst. Range is 10 ns to 10 ms. Each pulse in the pulse burst will have the same pulse width.

Num of Pulses per Burst Number of pulses in a burst. Range is 1 to 300. Burst Period The duration of a burst, or the repetition interval of the pulse burst. Range

is 200 ns to 10 s. Note that the burst period must be equal or greater than the PRI times the number of pulse in the pulse burst.

Burst Mode 2/2 Pressing this softkey displays the second menu screen.

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Modulation Operation Giga-tronics 2500B Series Microwave Signal Generators

PM Menus

Submenu

Parameter

Figure 32: PM Burst Mode Menu 2

PM Burst Menu 2

(see Figure 32)

Trigger Type You can choose from three different trigger types by using the softkey, or the Step Up or Step Down keys. The three trigger types are:

Continuous Triggered: This selection has two parameters:

o Trigger Polarity: Can select a rising edge or falling edge as the trigger

using the softkey or Step Up/Step Down keys

o RF Pulse Delay: Use the rotary knob, Step Up/Step Down keys, or the

numeric keypad to adjust the amount of delay before the start of the pulse burst. Limits: ≥ 100.0 ns to 1 s.

Gated: This selection has a single parameter:

o Trigger In: Can be set to Active High or Active Low using the rotary

knob, Step Up/Step Down keys, or adjacent softkey.

Sync Out Delay Sets the amount of delay for the signal at the PM SYNC OUT connector on the rear of the 2500B (see Figure 6 on page 19).

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Giga-tronics 2500B Series Microwave Signal Generators Modulation Operation

5.9 Generate an External Pulse-Modulated Signal

This procedure describes how to set up the 2500B to generate a signal that is pulse modulated by an external source. When this type of pulse modulation is used, the RF output signal is pulsed according to the signal that is applied to the

rear-panel PULSE IN/PM TRIG IN connector. Figure 33 shows an example of this with the input polarity of the PULSE IN/PM TRIG IN signal set to active high.

Figure 33: Pulse Modulation Using an External Modulation Source

In this procedure, a PM signal is generated with the following characteristics:

Carrier frequency = 2.00 GHz Carrier power = 1.00 dBm External modulating signal pulse width = 1 ms External modulating signal pulse repetition interval (PRI) = 2 ms

Equipment and Materials

External PM modulation source (see specifications in Table 54 on page 96) Cables and connectors for connecting the PM modulation source to the 2500B Cables and connectors for connecting device to be tested to the 2500B RF Output

Operation Manual, Part Number 34737, Rev C, June 30, 2011 Page 65

Modulation Operation Giga-tronics 2500B Series Microwave Signal Generators

Softkey

Generate an Externally Pulse-Modulated Signal

Step

Action

Perform steps 1 through 10 of the procedure Generate a CW Signal on page 24 to set the frequency and power level of the carrier.

Connect a TTL pulse source to the PULSE IN/PM TRIG IN connector on the rear of the instrument, and set it for the following characteristics:

Pulse width = 1 ms Pulse repetition interval (PRI) = 2 ms

Press to display the PM Main menu, then press PM Ext Menu.

Select PM, and use or press PM again to set PM to On (as indicated on the display).

Select Input Polarity, and choose the appropriate polarity setting using . NOTE:

With an Active High setting, a TTL high level at the PULSE IN/PM TRIG IN connector turns on the

carrier at the RF output.

With an Active Low setting, a TTL high level at the PULSE IN/PM TRIG IN connector turns off the

carrier at the RF output.

If you want to delay the signal at the PM SYNC OUT connector on the rear of the 2500B: Select

Sync Out Delay, and enter the desired sync pulse delay setting using the numeric keypad, , or . Limits of delay: ≥ 50 ns; ≤ 10 ms

If the RF ON indicator is not lit, press the RF ON button to enable the RF output (see Figure 3 on page

11). NOTE: When the RF output is enabled, the RF ON indicator is blue.

Verify that the Unleveled indicator is not illuminated. NOTE: If the Unleveled indicator is lit, then the combination of output power level, power offset,

power slope, and step attenuator mode (if applicable) is set inappropriately, and the RF output is unleveled. Adjust the combination of settings until the Unleveled indicator turns off.

End of Procedure

Softkey

Table 26: Generate an Externally Pulse Modulated Signal

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Giga-tronics 2500B Series Microwave Signal Generators Special Modes

Chapter 6 Special Modes

The 2500B has special modes that accommodate a wide variety of test configurations. These modes are:

Cable Correction; Creates a power level correction-versus-frequency table to change the power output of the

2500B. The cable correction table is created based on a power measurement procedure performed prior to normal testing. If the normal test setup is changed, the power measurement procedure must be performed again in order to re-create the cable correction table. See page 68.

External ALC; Uses a constant feedback loop to measure the power level externally, typically at the DUT.

External ALC operation allows automatic adjustment of the RF power output of the 2500B to maintain a constant, known power level at the DUT. See page 71.

External frequency reference: Uses an external 10 MHz or 100 MHz source as the frequency reference for the

2500B. See page 74.

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Special Modes Giga-tronics 2500B Series Microwave Signal Generators

6.1 Use Cable Correction

Cable Correction allows you to adjust the output power of the 2500B to compensate for losses created by connecting devices such as RF cables, connectors and other RF devices. The maximum correction is less than 10 dB, and depends on the absolute power output level. The power correction cannot exceed the maximum or minimum power output within a given setting of the step attenuator.

This function creates a user correction table of 1001 points for the frequency range of the unit. The power output for frequencies between the correction points is determined using a linear interpolation algorithm for the first frequency points above and below the selected frequency.

Required Equipment

Model 2500B series Microwave Signal Generator with firmware version 4.09 or higher Giga-tronics 8650A or 8650B series Universal Power Meter Giga-tronics 803XXA series CW Power Sensor, or other sensor appropriate to the frequency range and signal

type to be calibrated (with power sensor cable)

BNC Male to Male Coaxial Cable RS-232 Null Modem Cable, Male to Male (DB9)

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Use Cable Correction

Step

Action

Configure the 8650A/B series Universal Power Meter

On the front of the 8650A/B series Power Meter, select the following:

1. Meter Setup

2. Config

On the front of the 8650A/B series Power Meter, press the right arrow key to select RS-232; see Figure

34.

Figure 34: 8650A/B Universal Power Meter; Front Panel Controls

Select Config.

On the 8650A/B series Power Meter, set the RS-232 parameters as shown below. Use the Up/Down Arrow keys to change the values of the parameters (see Figure 34).

Baud Rate; 38400 Data Bits; 8 Parity; None Stop Bits; 1

Press OK twice to return to the power meter main menu.

Setup the Equipment

Softkey

Table 27: Use Cable Correction

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Special Modes Giga-tronics 2500B Series Microwave Signal Generators

Use Cable Correction

Step

Action

Refer to for the following steps.

Figure 35: Cable Connection Setup

Connect the null modem cable between the RS-232 ports on the rear of the 2500B and 8650A/B series Power Meter.

Connect the BNC cable to these two points:

SYNC OUT connector on the rear of the 2500B Gate/Trig Input on the rear of the 8650A/B series Power Meter

Connect the power sensor into the RF path to be characterized. Connect the sensor to be as close as possible to the point where you need the most control over the power level.

10.

On the front of the 2500B, press .

11.

Select Cable Cal Menu.

12.

Select Device Name, and select the Giga-tronics 8650A/B series Power Meter using

or .

13.

Select Interface.

14.

Press Cable Cal to begin the swept frequency characterization.

15.

After the frequency sweep is completed, a cable correction table will be generated and automatically applied to the output of the 2500B. The first line in the Cable Cal menu will change to Cable Cal Stored. The cable calibration will apply to the output of the 2500B until the Clear Cable Cal button in the Cable Cal menu is pressed.

End of Procedure

Softkey

System

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Giga-tronics 2500B Series Microwave Signal Generators Special Modes

6.2 Use External ALC

One application of this procedure would be a test setup where cables and fixtures connecting to the DUT incur significant losses, and you want to deliver a precise, known power level to the DUT under dynamic conditions.

With External Automatic Level Control (ALC), the power level close to the DUT is sampled by a power meter or crystal detector, and the sample is used to generate a signal that is connected to the 2500B. This signal is used to automatically adjust the RF output power of the 2500B to compensate for the power lost in the cables and fixture. See Figure 36 below.

NOTE: The example procedures in this section use specific parameters to illustrate how to setup the 2500B. You can use this procedure for real-life situations by simply changing the parameters to fit your needs.

This section describes two methods for using External ALC:

Use External ALC with a crystal (diode) detector; see Table 28 on page 72. Use External ALC with a Power meter; see Table 29 on page 73.

Figure 36: Setup for External ALC

Note the following about using external ALC:

ALC can be used in CW, Ramp, and Pulse modes only. The output of the 2500B is typically sampled through a directional coupler or power splitter. The signal is detected

using a positive or negative crystal (diode) detector or power meter.

External ALC response with the instrument configured for Pulse Modulation varies according to duty cycle of the

signal being sampled. Low duty cycles result in a slower response time for the instrument to level.

Level control for External ALC operation using crystal detectors are described in dBV units. The crystal detector output may vary for power and frequency. Because of the variability of the crystal detector

output, it may be necessary to characterize the crystal detector output with a power reference standard.

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Special Modes Giga-tronics 2500B Series Microwave Signal Generators

External ALC Using a Crystal (Diode) Detector

Step

Action

Connect the RF output of the 2500B to a power splitter or directional coupler that is placed as close to the DUT as possible. See Figure 36 on page 71.

Connect the input of the crystal detector to the appropriate port of the power splitter or directional coupler.

Connect the output of the crystal detector to the EXT ALC connector on the rear panel using an appropriate cable.

Press , then press System Menu.

Select ALC Leveling.

Use ALC Leveling or to select Positive Diode or Negative Diode. The choice depends on the type of detector used.

Press .

Select Frequency, and enter the desired CW frequency using the keypad, , or

Select Power and enter the output level using the keypad, , or . NOTE: When entering a new level setting using the keypad, use the dBm or dB Units buttons. Units are

assumed to be in dBV.

10.

If the RF ON indicator is not lit, press the RF ON button to enable the RF output. The RF ON indicator is illuminated blue when the RF Output is enabled.

End of Procedure

Softkey

System

Table 28: External ALC Using a Crystal (Diode) Detector

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Giga-tronics 2500B Series Microwave Signal Generators Special Modes

External ALC Using a Power Meter

Step

Action

Connect the sensor of the power meter to the appropriate port of the power splitter or directional coupler. See Figure 36 on page 71.

Connect the Analog Out output of the power meter to the EXT ALC connector on the rear panel of the 2500B.

Adjust the Analog Out range of the power meter from 0.0005 to 2 Volts.

Press , then select System Menu.

Select ALC Leveling.

Select the Power Meter setting using or by repeatedly pressing ALC Leveling.

Press .

Select Frequency, and enter the desired CW frequency using the numeric keypad,

, or .

Select Level and enter the desired output level using the numeric keypad, , or

NOTE: When entering a new level setting using the numeric keypad, use the dBm or dB Units buttons. Units are assumed to be in dBV. Use the following formula to convert to Volts to dBV:

dBV = 20 log

(V) for a 50 Ohm system.

10.

If the RF ON indicator is not lit, press the RF ON button to enable the RF Output. When the RF Output is enabled, the RF ON indicator is illuminated blue.

End of Procedure

Softkey

System

Softkey

System

Table 29: External ALC Using a Power Meter

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Special Modes Giga-tronics 2500B Series Microwave Signal Generators

Use an External Frequency Reference

Step

Action

Verify that the RF output is NOT energized by checking the RF on/off indicator on the front of the 2500B (see Figure 3 on page 11). If the indicator is lit, press the button to de-energize

the RF output.

Energize the external frequency reference and let it warm up according to the manufacturer’s recommendations.

NOTE 4: Observe Notes 1 and 2 above regarding the integrity and specifications of the reference signal.

On the rear of the 2500B, locate the EXT REF IN connector (see Figure 6 on page 19).

Connect the external frequency reference to the EXT REF IN connector on the rear of the 2500B. NOTE: The Ext Ref indicator on the front panel (see Figure 3 on page 11) illuminates when an

energized, appropriate external frequency reference is connected to the EXT REF IN connector.

Proceed to use the 2500B as you normally would.

End of Procedure

RF ON

6.3 Use the External Reference Input

Internally, the 2500B generates a 100 MHz reference signal for the instrument. This reference signal is normally phaselocked to a high-stability internal 10 MHz signal.

However, if an external 10 MHz or 100 MHz signal is connected to the rear EXT REF IN connector, the internal 100 MHz reference signal phase-locks to this external signal. When an external signal is connected to the EXT REF IN connector, the instrument detects and automatically routes it through the instrument.

Required Equipment

External signal reference (see Table 39 on page 88 for reference specifications) Cables and connectors to connect the equipment

NOTE 1: The example procedure in this section uses specific parameters to illustrate how to setup the 2500B. You can use this procedure for real-life situations by simply changing the parameters to fit your needs.

NOTE 2: If the external reference has excessive noise or drift, this will degrade the performance of the 2500B. The procedure below describes how to use the EXT REF IN connector on the rear of the 2500B.

Table 30: Use an External Frequency Reference

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Giga-tronics 2500B Series Microwave Signal Generators System Menus

Chapter 7 System Menus

7.1 System Menus Description

The System menus gives you access to system-level settings, such as memory storage locations, GPIB address configuration, display contrast, and system volume control. System information, including the model number, serial number, firmware version, etc., can also be displayed.

Pressing the System menu button opens the main System menu, which consists of four submenus as shown in Figure 37.

Any submenu can be opened by pressing the softkey next to the submenu’s name. All parameters shown in the System

menus can be modified once selected by their adjacent softkey. Table 31 on page 76 describes the menu items of the System menus.

Figure 37: System Main Menu and Submenus

Operation Manual, Part Number 34737, Rev C, June 30, 2011 Page 75

System Menus Giga-tronics 2500B Series Microwave Signal Generators

System Menus

Submenu

Action or Parameter

Figure 38: System Menu

System Menu (see Figure 38)

Attenuation Provides control of the step attenuator if it is installed in the instrument.

The step attenuator option can insert up to 90 dB of attenuation (110 dB with option

27) into the RF output path of the instrument.

It is switchable in 10 dB steps Can be set to automatically switch as the instrument’s power level is varied, or it can

be manually set to insert a fixed amount of attenuation.

ALC Leveling This menu item allows you to set the instrument's ALC input. The ALC input settings are;

Internal Positive Detector Negative Detector Power Meter.

External ALC enables the instrument to compensate for device transmission losses without user intervention.

External Tune Input This function allows you to tune the output frequency of the 2500B over a range of approximately 20 ppm (2 ppm with option 28) using an analog tuning voltage of 0 to +10 Volts applied to the Ref Tune input on the rear panel. Pressing this softkey enables and disables this feature.

Table 31: System Menus

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Giga-tronics 2500B Series Microwave Signal Generators System Menus

System Menu - Connectivity

Submenu

Action or Parameter

Figure 39: Connectivity Menu

Connectivity Menu

(see Figure 39)

GPIB Address Allows you to set the instrument’s General-Purpose Interface Bus (GPIB) address. The GPIB address range is 1 to 30.

Baud Rate Sets the data transfer rate over the RS-232 port on the rear panel of the 2500B. This menu item lets you can select from the following rates :

1200 2400 4800 9600 19200 38400 115200

Table 32: System Menu - Connectivity

Operation Manual, Part Number 34737, Rev C, June 30, 2011 Page 77

System Menus Giga-tronics 2500B Series Microwave Signal Generators

System Menu – Service Submenu

Submenu

Action or Parameter

Figure 40: Service Menu

Service Menu

(see Figure 40)

Save Allows you to save the current state of the instrument to non-volatile memory, so that the saved state can subsequently be restored. The 2500B contains ten registers, numbered 0 through 9, in which instrument states can be saved. Note that saving an instrument state to a given register overwrites any state that might have previously been stored in that register.

To save the current instrument configuration to a given register;

1. Select the Save menu item

2. Use the numeric keypad to enter the number of the register into which you wish to save the

configuration (the step up/step down buttons and rotary knob cannot be used for this).

3. Press any Units button. Recall This menu item allows you to recall a previously saved instrument state from any of the ten

storage registers contained in the instrument’s non-volatile memory. The parameter area in the display shows the following text:

From Register (X)

Where X is the list of registers, separated by commas that currently have an instrument state saved in them. For example, if instrument states are currently stored in registers 1, 2, and 5, the parameter area would read as follows:

From Register (1, 2, 5)

If none of the registers have instrument states saved to them, as would be the case after the instrument’s memory is cleared, the following is displayed in the parameter area:

No register has been saved

To recall a previously saved instrument configuration, press the Recall softkey, enter the number of the register from which you wish to recall the configuration using the numeric keypad, and then press any units button.

Only the numeric keypad can be used to enter a register number; the step up/step down buttons and rotary knob cannot be used.

Table 33: System Menu – Service Submenu

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Giga-tronics 2500B Series Microwave Signal Generators System Menus

System Menu – Service Submenu

Submenu

Action or Parameter

Service Menu, Continued

(see Figure 40)

Contrast This menu item allows you to set the contrast of the instrument’s front panel display. The contrast range is 1 to 15, where 1 represents most contrast and results in the darkest display, and 15 represents least contrast and results in the lightest display.

Sound This menu item allows you to enable or disable (mute) the system sound. The available selections are ON and MUTE. When Sound is set to ON, the instrument provides audio feedback whenever a button is pressed or the knob is rotated, and an operational error notification is emitted when an error condition occurs, such as when an improper button sequence is pressed, a parameter limit is exceeded.

System Menu – Ethernet Submenu

Submenu

Action or Parameter

Figure 41: Ethernet Menu

Ethernet Menu

(see Figure 41)

The Ethernet Menu allows you to set up the 2500B for remote operations using the LAN connection.

Settable menu items: DHCP Allows you to configure the 2500B Dynamic Host Configuration Protocol to be set manually

or allow a DHCP server to obtain the IP and Subnet Mask. When the DHCP is set to Off, the previously stored static IP address will be displayed.

IP Address Allows you to set the instrument’s IP (Internet Protocol) address. The range for each of the sections is 0 to 255.

Subnet Mask Allows you to set the instrument’s Subnet Mask. The range for each of the sections is 0 to 255.

Link Status Indicates whether the 2500B Ethernet connection is established or disconnected.

Table 34: System Menu –Ethernet Submenu

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System Menus Giga-tronics 2500B Series Microwave Signal Generators

7.2 Use the Ref Tune Function

Why use this procedure: Use this function when you want to phase-lock the output frequency of the 2500B with a stable, external frequency source. See Figure 42 below.

The Reference Tune (Ref Tune) function allows you to adjust the output frequency of the 2500B over a range of approximately 20 ppm (2 ppm with option 28) when the phase-lock loop with external source applies a 0 to +10 V control voltage to the REF TUNE input on the rear panel.

Figure 42: Reference Tune Setup

Note the following about the Ref Tune function:

It is expected that the unlock (UNLK) message will appear in the upper right-side of the display when the Ref Tune

function is enabled. The 2500B is “unlocked”. The user must determine the appropriate parameters necessary to lock the 2500B to the external frequency source.

The tuning voltage must not exceed +15 Volts and must not go more negative than -1 Volt. The instrument's phase noise performance may be degraded when Ref Tune is enabled. The Ref Tune input is a high impedance input and has a 3 dB bandwidth of approximately 1 kHz that is set by a pole

consisting of 150 Ω and 1 µF as shown in the Figure 43.

Figure 43: Ref Tune Input Circuit

Additional resistance in the driving source will lower the bandwidth accordingly. The tuning sensitivity at the instrument's output frequency is approximately 2 ppm/Volt (0.2 ppm/V with option 28) but should be carefully characterized for the specific DC Voltage range being applied. A nominal tuning voltage of 4.5 Volts corresponds to the instrument's nominal frequency setting.

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Giga-tronics 2500B Series Microwave Signal Generators System Menus

Use the Ref Tune Feature

Step

Action

Connect a cable with a BNC connector between the REF TUNE connector on the rear panel of the 2500B and the controlling source.

On the 2500B front panel, press .

Select System Menu. External Tune Input will appear as one of the softkeys.

Enable and disable the Reference Tune input by:

Toggling External Tune Input Pressing .

End of Procedure

Softkey

System

Table 35: Use the Ref Tune Feature

Operation Manual, Part Number 34737, Rev C, June 30, 2011 Page 81

Language Menus Giga-tronics 2500B Series Microwave Signal Generators

Chapter 8 Language Menus

There are three Language menus that allow you to choose the language to be used by the instrument during remote operation.

NOTE: Complete information for remotely programming the 2500B via a host computer is available in the 2500B Programming Manual, Part Number 34783.

Displaying the Language Menus

In Local mode (front panel operation), access the Language menus at any time by pressing the LOCAL button.

NOTE: Pressing the LOCAL button when the instrument is in the remote operating mode returns it to local operating

mode.

You can leave the Language menus at any time by pressing any of the Menu buttons on the front panel, or by going

in to Remote mode.

You can navigate between the three Language menus by pressing the bottom softkey on the front panel. See Figure

44.

8.1 Language Menu Description

Figure 44 shows Language Menu 1. The following pages describe the settable items in the three Language menus.

Figure 44: Language Menu 1

Press the bottom-right softkey to toggle between the three Language Menus.

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Giga-tronics 2500B Series Microwave Signal Generators Language Menus

Language Menus

Parameter

Press LOCAL on the front panel of the 2500B to display:

Language Menu 1

(see Figure 44)

Language Menu 1 and Language Menu 2 allow you to view and choose the language to be used by the instrument during remote operation. Some of the remote language choices are standard, and some are optional. The remote language that is used by the instrument corresponds to the Language menu item that is currently selected.

Settable items in Language Menu 1 are: SCPI This menu item allows you to select Standard Commands for Programmable

Instruments (SCPI) as the language to be used by the instrument during remote operations. SCPI is one of the standard remote language choices that are available. To choose SCPI as the remote language, select this menu item.

GT12000 This menu item allows you to select the Giga-tronics Series 12000A native command set as the language to be used by the instrument during remote operations.

GT9000 This menu item allows you to select GT 9000 command set as the remote control language to be used by the instrument using the instrument's GPIB or RS-232 port.

GT7000 This menu item allows you to select GT 7000 command set as the remote control language to be used by the instrument using the instrument's GPIB or RS-232 port.

GT900 This menu item allows you to select GT 900 command set as the remote control language to be used by the instrument using the instrument's GPIB or RS232 port.

Language 2/3 Pressing this softkey invokes Language Menu 2 in the display. Language Menu 2 is described on the next page.

Table 36: Language Menus

Operation Manual, Part Number 34737, Rev C, June 30, 2011 Page 83

Language Menus Giga-tronics 2500B Series Microwave Signal Generators

Language Menus

Parameter

Figure 45: Language Menu 2

Press softkey Language 2/3 to display:

Language Menu 2

(see Figure 45)

HP8340 This menu item allows you to select HP 8340 command emulation as the language to be used by the instrument during remote operations.

HP8350 This menu item allows you to select HP 8350 command emulation as the language to be used by the instrument during remote operations.

HP8360 This menu item allows you to select HP 8360 command emulation as the language to be used by the instrument during remote operations.

HP8370 This menu item allows you to select HP 8370 command emulation as the language to be used by the instrument during remote operations.

HP8663 This menu item allows you to select HP 8663 command emulation as the language to be used by the instrument during remote operations.

Language 3/3 Pressing this softkey displays Language Menu 3. Language Menu 3 is described on the next page.

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Giga-tronics 2500B Series Microwave Signal Generators Language Menus

Language Menus

Parameter

Figure 46: Language Menu 3

Press softkey Language 3/3 to display:

Language Menu 3

(see Figure 46)

Language Menu 3 allows you to view and choose the language to be used by the instrument during remote operation. The remote language that will be used by the instrument corresponds to the Language menu item that is currently selected.

Settable items in this menu are: HP8673 This menu item allows you to select HP 8673 command emulation as the

language to be used by the instrument during remote operations. Systron Donner This menu item allows you to select Systron Donner command

set as the remote control language to be used by the instrument using the instrument's GPIB or RS-232 port.

Wavetek 90X This menu item allows you to select Wavetek 90X command set as the remote control language to be used by the instrument using the instrument's GPIB or RS-232 port.

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Performance Verification Giga-tronics 2500B Series Microwave Signal Generators

General Specifications

Parameter

Specification

Operating Temperature

0 °C to 55 °C

Environmental

Conforms to MIL-PRF-28800F, Class 3

Safety

EN61010

Emissions

EN61326

Approvals

CE Marked

Power

90 to 253 VAC, 47 to 440 Hz, 300 Watts typical, 350 Watts maximum

Fuse Rating

3 A Slow-Blow (SB)

Width 1 (without rack handles)

16.75 inches (425.5 mm)

Width 1 (with rack handles)

19 inches (482.6 mm)

Depth

21 inches (533.4 mm)

Height

3U (5.25 inches, 133.4 mm)

Weight

Less than 35 lbs. (15.9 kg)

See the next page for drawings with dimensions of the 2500B.

Chapter 9 Performance Verification

This section is comprised of two sub-sections:

Specifications; contains the operating specifications of the 2500B Verification; contains the procedures for verifying that the 2500B is operating within its design specifications

9.1 Specifications

All specifications apply over a 0 °C to 55 °C range after 30 minutes of warm-up time, unless otherwise stated.

Table 37: General Specifications

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Giga-tronics 2500B Series Microwave Signal Generators Performance Verification

Figure 47: 2500B Mechanical Specifications

NOTE: These drawings show the 2500B with the rack-mounting hardware installed.

Operation Manual, Part Number 34737, Rev C, June 30, 2011 Page 87

Performance Verification Giga-tronics 2500B Series Microwave Signal Generators

2500B Series Model Frequency Ranges

Model Number

Frequency Range

RF Output Connector

2502B

100 kHz to 2.5 GHz

Type-N (F)

2508B*

2 GHz to 8 GHz

Type-N (F)

2520B*

2 GHz to 20 GHz

SMA (F)

2526B*

2 GHz to 26.5 GHz

SMA (F)

2540B*

2 GHz to 40 GHz

2.92 mm (F)

2550B*

2 GHz to 50 GHz

2.4 mm (F)

* Adding Option 18 to these models extends the frequency range down to 100 kHz.

Frequency Specifications

Parameter

Specification

Accuracy

Same as time-base

Resolution

0.001 Hz

Power Slope

Adjustable up to 0.5 dB/GHz

Internal Reference Output 10 MHz

TTL level into 50 Ω

100 MHz

> +5 dBm square wave into 50 Ω

Aging rate 1

< 5 x 10

-10

/day

Temperature stability

< 2.5 x 10-8

External Frequency Reference Input

Frequency

10 MHz or 100 MHz

Frequency Deviation

± 1 ppm

Recommended input level

10 MHz: > -5 dBm into 50 Ω

100 MHz: > +5 dBm to < +8 dBm into 50 Ω

Reference Tuning Voltage Range

0 to 10V

Sensitivity

2 ppm/Volt nominal, or

0.2 ppm/V nom. with Opt 28

Lock/Level indicator (CW mode only)

Sync Out = +5 V (TTL High)

After 30 days

Temperature stability over operating range of 0 °C to +55 °C after 30 days

Table 38: 2500B Series Model Frequency Ranges

Table 39: Frequency Specifications

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Giga-tronics 2500B Series Microwave Signal Generators Performance Verification

Frequency Bands

Band

Frequency

N (Band index)

0.1 to ≤ 10 MHz

N/A

> 10 to ≤ 15.625 MHz

512 2 > 15.625 to 31 ≤ MHz

256

> 31 to 63 MHz

128 4 > 63 to ≤ 125 MHz

64 5 > 125 to ≤ 250 MHz

32 6 > 250 to ≤ 500 MHz

16 7 > 500 to ≤ 1000 MHz

8 8 > 1 to ≤ 2 GHz

> 2 to ≤ 4 GHz

> 4 to ≤ 10.1 GHz

> 10.1 to ≤ 20.2 GHz

1/2

> 20.2 to ≤ 39.6 GHz

1/4

> 39.6 to ≤ 50 GHz

1/6

1 Band 12 frequency range extends to 40 GHz for model 2540B

Table 40: Frequency Bands

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Performance Verification Giga-tronics 2500B Series Microwave Signal Generators

Spectral Purity

Harmonics

Maximum leveled output power or +10 dBm, whichever is lower. Specifications for harmonics above instrument frequency range are nominal.

100 kHz to 10 MHz

-30 dBc

> 10 MHz to 100 MHz

-40 dBc

> 100 MHz to 39.6 GHz

-50 dBc

> 39.6 to 50 GHz

-30 dBc nominal

Sub-Harmonics

Maximum leveled output power or +10 dBm, whichever is lower. Specifications for Sub-harmonics above instrument frequency range are nominal.

100 kHz to 2 GHz

-80 dBc

> 2 to 20.2 GHz

-60 dBc

> 20.2 to 50 GHz

-40 dBc

Spurious

Specifications are for offsets > 300 Hz. Specification is -45 dBc + 20 log(1/N) dBc nominal for offsets < 300 Hz.

100 kHz to 10.1 GHz

-65 dBc

> 10.1 to 20.2 GHz

-58 dBc

> 20.2 to 39.6 GHz

-50 dBc

> 39.6 to 50 GHz

-40 dBc

Residual FM (typical)

50 Hz to 15 kHz Bandwidth

100 kHz to 20.2 GHz

< 6 Hz

> 20.2 to 39.6 GHz

< 12 Hz

> 39.6 to 50 GHz

< 18 Hz

AM Noise (typical)

Offset > 5 MHz at maximum leveled power. Applies in CW only.

100 kHz to 2 GHz

-130 dBm/Hz

> 2 to 20.2 GHz

-145 dBm/Hz

> 20.2 to 50 GHz

-132 dBm/Hz

1, 2

Specification for model 2540B extends to 40 GHz

Table 41: Spectral Purity

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Giga-tronics 2502B, 2550B, 2508B, 2520B, 2526B Operation Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

2500B Series Microwave Signal Generators

Table of Contents

List of Tables

List of Figures

Chapter 1 Safety and Manual Conventions

1.1 Unsafe Operating Conditions

1.2 Safety and Manual Conventions

1.3 Personal Safety Alert

1.4 Equipment Safety Alert

1.5 Notes

1.6 Graphic Symbols for Front Panel Buttons

Chapter 2 Introduction

2.1 Overview

2.2 Giga-tronics 2500B Microwave Signal Generator Summary

2.3 Configuration Information

2.3.1 Special Configurations

2.4 Receiving and Inspection

2.5 Prepare the 2500B for Use

2.5.1 Cooling Considerations

2.5.2 AC Power Requirements

2.5.3 Start-up the 2500B

2.5.4 Reset the 2500B to Factory-Default Values

2.5.5 Replace the AC Line Fuse

2.6 Shipping, Repair, and Calibration

2.6.1 Shipping the 2500B

2.6.2 Repairs

2.6.3 Calibration

2.7 2500B Front Panel

2.7.1 Menus

2.7.2 Menu Structure

2.7.3 Access the Menus

2.7.4 Softkeys

2.7.5 Modify Menu Parameters

2.7.6 Modify the Step Size

2.8 2500B Rear Panel

Chapter 3 CW Operation

3.1 CW Menu Description

3.2 Generate a CW Signal

Chapter 4 Ramp Operation

4.1 Ramp Menu Description

4.2 Generate a Frequency-Swept Signal

4.3 Generate a Power-Swept Signal

Chapter 5 Modulation Operation

5.1 AM Menu Description

5.2 Generate an Internally Modulated AM Signal

5.3 Generate an Externally Modulated AM Signal

5.4 FM Menu Description

5.5 Generate an Internally Modulated FM Signal

5.6 Generate an Externally Modulated FM Signal

5.7 Generate an Externally Phase Modulated Signal

5.8 Pulse Modulation (PM) Menu Description

5.9 Generate an External Pulse-Modulated Signal

Chapter 6 Special Modes

6.1 Use Cable Correction

6.2 Use External ALC

6.3 Use the External Reference Input

Chapter 7 System Menus

7.1 System Menus Description

7.2 Use the Ref Tune Function

Chapter 8 Language Menus

8.1 Language Menu Description

Chapter 9 Performance Verification

9.1 Specifications