Agilent N5181A Users Guide

User’s Guide

Agilent Technologies

N5181A/82A MXG Signal Generators

This guide applies to the followin g sign al ge nerator models:

N5181A MXG Analog Signal Generator N5182A MXG Vector Signal Generator

Because of our continuing efforts to improve our products through firmware and hardware revisio ns, si gn al gene rato r des ign and operation may vary from descriptions in this guide. We recommend that you use the latest revision of this guide to ensure that you have up-to-date product information. Compare the print date of this guide (see bottom of page) with the latest revision, which can be downloaded from the followin g website:

http://www.agilent.com/find/mxg

Manufacturing Part Number: N5180- 90003

Printed in USA

September 2006

Notice

The material contained in this document is provided “as is”, and is subject to being changed, without notice, in future editions.

Further, to the maximum extent permitted by applicable law, Agilent disclaims all warranties, either express or implied with regard to this manual and to any of the Agilent products to which it pertains, including but not limited to the implied warranties of merchantability and fitness for a particular purpose. Agilent shall not be liable for errors or for incidental or consequential damages in connection with the furnishing, use, or performance of this document or any of the Agilent products to which it pertains. Should Agilent have a written contract with the User and should any of the contract terms conflict with these terms, the contract terms shall control.

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Contents

1 Signal Generator Overview

Signal Generator Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2

Front Panel Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

1. Host USB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

2. Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

3. Softkeys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

4. Numeric Keypad . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

5. Arrows and Select. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

6. Page Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4

7. MENUS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4

8. Trigger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4

9. Local Cancel/(Esc) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4

10. Help . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4

11. Preset and User Preset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4

12. RF Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

13. RF On/Off and LED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

14. Mod On/Off and LED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

15. Page Down . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

16. I Input (vector models only) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

17. Q Input (vector models only) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

18. Knob. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6

19. Incr Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6

20. Return . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6

21. More and LED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6

22. Power Switch and LEDs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6

Front Panel Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7

1. Active Function Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7

2. Frequency Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7

3. Annunciators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7

4. Amplitude Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8

5. Error Message Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8

6. Text Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8

7. Softkey Label Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8

Rear Panel Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

1. AC Power Receptacle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

2. SWEEP OUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

3. AM. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

4. FM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

5. PULSE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

6. TRIG IN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

7. TRIG OUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

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8. REF IN. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

9. 10 MHz OUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

10. GPIB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

11. LAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

12. Device USB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Digital Modulation Connectors (vector models only) . . . . . . . . . . . . . . . . . . . . . . . . . . 12

I OUT, QOUT, OUT, OUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

EXT CLOCK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

EVENT 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

PAT TRIG IN. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

DIGITAL BUS I/O . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

AUX I/O. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

2 Setting Preferences & Enabling Options

User Preferences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Display Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Power On and Preset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Front Panel Knob Resolution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Setting Time and Date . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Upgrading Firmware. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Remote Operation Preferences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Configuring the GPIB Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Configuring the LAN Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Enabling LAN Services: Browser, Sockets, and VXI- 11. . . . . . . . . . . . . . . . . . . . . . . . . 20

Enabling an Option . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Viewing Options and Licenses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

3 Basic Operation

Presetting the Signal Generator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Viewing Key Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Entering and Editing Numbers and Text . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Entering Numbers and Moving the Cursor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Entering Alpha Characters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Example: Using a Table Editor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Setting Frequency and Power (Amplitude) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Example: Configuring a 700 MHz, −20 dBm Continuous Wave Output . . . . . . . . . . . . . . 26

Configuring a Swept Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Step Sweep . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

List Sweep . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Example: Using a Single Sweep . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

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Example: Manual Control of Sweep . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Routing Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Modulating the Carrier Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Viewing, Saving, and Recalling Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Viewing a Stored File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

Saving and Recalling Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Working with Instrument State Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Selecting Internal or External Media . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Reading Error Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

Error Message Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

4 Optimizing Performance

Using User Flatness Correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

Basic Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

Example: A 500 MHz to 1 GHz Flatness Correction Array with 10 Correction Values . . . . 45

Recalling and Applying a User Flatness Correction Array . . . . . . . . . . . . . . . . . . . . . . 46

Using Unleveled Operating Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

ALC Off Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Power Search Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

Using an Output Offset, Reference, or Multiplier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

Setting an Output Offset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

Setting an Output Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

Setting a Frequency Multiplier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

5 Using Analog Modulation (Option UNT Only)

The Basic Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

Using an External Modulation Source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

Removing a DC Offset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

6 Using Puls e Modulatio n ( Option UNU)

Pulse Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

The Basic Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

7 Basic Digital Operation—No BBG Optio n Installed

I/Q Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

Configuring the Front Panel Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

Agilent N5181A/82A MXG Signal Generators User’sGuide v

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8 Basic Digital Operation (Optio n 651 /652/654)

Waveform File Basics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68

Signal Generator Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68

Dual ARB Player . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68

Storing, Loading, and Playing a Waveform Segment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

Storing/Renaming a Waveform Segment to Non- Volatile Memory (Internal or External Media) 70

Loading a Waveform Segment into BBG Media (Volatile Memory) . . . . . . . . . . . . . . . . . 71

Playing a Waveform Segment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

Setting the Baseband Frequency Offset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

Waveform Sequences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

Creating a Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

Viewing the Contents of a Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

Editing a Sequence. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

Playing a Sequence. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

Saving a Waveform’s Settings & Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

Viewing and Modifying Header Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

Viewing & Editing a Header without Selecting the Waveform . . . . . . . . . . . . . . . . . . . . 81

Using Waveform Markers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82

Waveform Marker Concepts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83

Accessing Marker Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87

Viewing Waveform Segment Markers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

Clearing Marker Points from a Waveform Segment . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

Setting Marker Points in a Waveform Segment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89

Viewing a Marker Pulse. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92

Using the RF Blanking Marker Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93

Setting Marker Polarity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94

Controlling Markers in a Waveform Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95

Using the EVENT Output Signal as an Instrument Trigger . . . . . . . . . . . . . . . . . . . . . . 97

Triggering a Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98

Trigger Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99

Trigger Source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100

Example: Segment Advance Triggering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101

Example: Gated Triggering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102

Example: External Triggering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104

Clipping a Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105

How Power Peaks Develop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

How Peaks Cause Spectral Regrowth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108

How Clipping Reduces Peak-to- Average Power. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109

Configuring Circular Clipping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112

Configuring Rectangular Clipping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113

vi Agilent N5181A/82A MXG Signal Generators User’sGuide

Contents

Scaling a Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114

How DAC Over-Range Errors Occur . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116

How Scaling Eliminates DAC Over- Range Errors. . . . . . . . . . . . . . . . . . . . . . . . . . . . 117

Setting Waveform Runtime Scaling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118

Setting Waveform Scaling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119

I/Q Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121

Using the Rear Panel I and Q Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122

Configuring the Front Panel Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124

I/Q Adjustments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125

I/Q Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127

9 Adding Real Time Noise to a Signal (Option 403)

Adding Real- Time Noise to a Dual ARB Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130

Using Real Time I/Q Baseband AWGN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132

10 Working in a Secure Environment

Understanding Memory Types. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134

Removing Data from Memory (Option 006 Only) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136

Erase All . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136

Erase and Overwrite All . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137

Erase and Sanitize All. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137

Secure Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137

Securing a Nonfunctioning Instrument . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138

Using the Secure Display (Option 006 Only) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139

11 Troubleshooting

Display. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142

The Display is Too Dark to Read. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142

Signal Generator Lock- Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142

RF Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143

No RF Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143

Power Supply Shuts Down . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143

No Modulation at the RF Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143

RF Output Power too Low . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143

Distortion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143

Signal Loss While Working with a Spectrum Analyzer . . . . . . . . . . . . . . . . . . . . . . . . 144

Signal Loss While Working with a Mixer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144

Agilent N5181A/82A MXG Signal Generators User’sGuide vii

Contents

Sweep . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146

Cannot Turn Off Sweep . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146

Sweep Appears Stalled . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146

Incorrect List Sweep Dwell Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146

List Sweep Information is Missing from a Recalled Register . . . . . . . . . . . . . . . . . . . . 146

Amplitude Does Not Change in List or Step Sweep . . . . . . . . . . . . . . . . . . . . . . . . . 146

Internal Media Data Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147

Instrument State Saved but the Register is Empty or Contains the Wrong State . . . . . . 147

External Media Data Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147

Instrument Recognizes External Media Connection, but Does Not Display Files . . . . . . . 147

Preset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147

The Signal Generator Does Not Respond . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147

Pressing Preset Performs a User Preset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147

Error Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148

Error Message Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148

Error Message File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148

Front Panel Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149

Self Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149

Licenses. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150

A Time- Based License Quits Working . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150

Cannot Load a Time- Based License. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150

Contacting Agilent Technologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151

Returning a Signal Generator to Agilent . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151

viii Agilent N5181A/82A MXG Signal Generators User’sG uide

Documentation Overview

Installation Guide

User’s Guide

Programming Guide

SCPI Reference

• Safety Information

• Receiving the Instr ument

• Environmental & Electrical Requirements

• Basic Setup

• Accessories

• Operation Verification

• Regulatory Information

• Instrument Overview

• Front Panel Operation

• Security

• Basic Troubleshooting

• Remote Operation

• Status Registers

• Creating & Downloading Files

• SCPI Basics

• Command Descriptions

• Programming Command Compatibility

Service Guide

• Troubleshooting

• Assembly Replacement

• Replaceable Parts

• Post- Repair Procedures

• Safety and Regula tor y Information

Key H el p

• Key function description

• Related SCPI commands

Press the Help hardkey, and then the key for which you wish help.

Agilent N5181A/82AMXG Signal Generators User’sGuide ix

x Agilent N5181A/82A MXG Signal Generators User’sGuide

1 Signal Generator Overview

• Signal Generator Features on page 2

• Front Panel Overview on page 3

• Front Panel Display on page 7

• Rear Panel Overview on page 9

Agilent N5181A/82AMXG Signal Generators User’sGuide 1

Signal Generator Overview Signal Generator Features

Signal Generator Features

• N5181A, analog models: 250 kHz to 1, 3, or 6 GHz

N5182A, vector models: 250 kHz to 3 or 6 GHz

• electronic attenuator

• step & list sweep of frequency, power, or frequency and power

vector models can include waveforms in list sweep

• user flatness correction

• automatic leveling control (ALC); power calibration

• 10 MHz reference oscillator with external output

• flexible reference input, 1 – 50 MHz (Option 1ER)

• GPIB, USB 2.0, and 100Base- T LAN interfaces

• analog modulation: AM, FM, and ΦM (Option UNT)

• external AM, FM, and ΦM inputs (Option UNT)

• pulse modulation (Option UNU)

• SCPI and IVI- COM driver

• 8648/ESG code compatible

• LXI Class C compliant

• external analog I/Q inputs (vector models)

• analog differential I/Q outputs (vector models, Option 1EL)

• arbitrary I/Q waveform playback up to 125 MSa/s (vector models, Option 654)

• with Signal Studio Software, vector models can generate 802.11 WLAN, W- CDMA, cdma2000, 1xEV- DO, GSM, EDGE, and more

For more details on hardware, firmware, software, and documentation features and options, refer to the data sheet shipped with the signal generator and available from the Agilent Technologies website.

1. Open: http://www.agilent.com/find/mxg

2. Select the desired model number.

3. In the options and price list section, click price list.

2 A gilent N5181A/ 82A MXG SignalGeneratorsUser’s Guide

Front Panel Overview

8. Tri gger

1. Host USB

2. Display

MXG Vector Signal Generator

N5181A 250 kHz - 6 GHz

3. Softkeys

4. Numeric Keypad

5. Arrows and Select

9. Local Cancel/(Esc)

6. Page Up

Signal Generator Overview

Front Panel Overvi ew

7. MENUS

and

10. Help

11. Preset and User Preset

12. RF Output

21. More and LED

22. Power Switch and LEDs

20. Return

18. Knob

19. Incr Set

16. I Input

15. Page Down

17. Q Input

14. Mod On/Off and LED

13. RF On/Off and LE

1. Host USB

Connector Type A

USB Protocol 2.0

Use this universal serial bus (USB) to connect a memory stick for data transfer. You can connect or disconnect a USB device without shutting down or restarting the signal generator. The instrument also has a rear- panel device USB connector (see page 11) used to remotely control the instrument.

2. Display

The LCD screen provides information on the current function. Information can include status indicators, frequency and amplitude settings, and error messages. Labels for the softkeys are located on the right- hand side of the display. See also, “Front Panel Display” on page 7.

3. Softkeys

A softkey activates the function indicated by the displayed label to the left of the key.

4. Numeric Keypad

The numeric keypad comprises the 0 through 9 hardkeys, a decimal point hardkey, a minus sign hardkey, and a backspace hardkey. See “Entering and Editing Numbers and Text” on page 24.

5. Arrows and Select

The Select and arrow hardkeys enable you to select items on the signal generator’s display for editing.

See “Entering and Editing Numbers and Text” on page 24.

Agilent N5181A/82AMXG Signal Generators User’sGuide 3

Signal Generator Overview Front Panel Overview

6. Page Up

In a table editor, use this hardkey to display a previous page. See “Example: Using a Table Editor” on

page 25. When text does not fit on one page in the display area, use this key in conjunction with the Page Down key (page 5) to scroll text.

7. MENUS

These hardkeys open softkey menus that enable you to configure instrument functions or access information.

See page 67

Reserved for future use.

See page 26

See page 27

Active only on vector models.

See page 53

See page 57

See page 35

See page 42

See page 15

See page 23

See page 38

8. Trigger

When trigger mode is set to Trigger Key, this hardkey initiates an immediate trigger event for a

function such as a list or step sweep.

9. Local Cancel/(Es c)

This hardkey deactivates remote operation and returns the signal generator to front panel control, cancels an active function entry, and cancels long operations (such an IQ calibration).

10. Help

Use this key to display a description of any hardkey or softkey. See “Viewing Key Descriptions” on

page 23.

11. Preset and User Preset

These hardkeys set the signal generator to a known state (factory or user- defined). See “Presetting

the Signal Generator” on page 23.

4 A gilent N5181A/ 82A MXG SignalGeneratorsUser’s Guide

12. RF Output

Signal Generator Overview

Front Panel Overvi ew

Connector Standard:

Option 1EM: Impedance:

Damage Levels 50Vdc, 2W maximum RF power

female Type- N Rear panel female Type- N

50Ω

13. RF On/Off and LE D

This hardkey toggles the operating state of the RF signal present at the RF OUTPUT connector. The RF On/Off LED lights when RF output is enabled.

14. Mod On/Off and LED

This hardkey enables or disables the modulation of the output carrier signal by an active modulation format. This hardkey does not set up or activate a format (see “Modulating the Carrier Signal” on

page 34).

The MOD ON/OFF LED lights when modulation of the output is enabled.

15. Page Down

In a table editor, use this hardkey to display the next page. See “Example: Using a Table Editor” on

page 25. When text does not fit on one page in the display area, use this key in conjunction with the Page Up key (page 4) to scroll text.

16. I Input (vector models only)

Connector Type: female BNC Impedance: 50Ω

Signal An externally supplied analog, in- phase component of I/Q modulation.

The signal level is = 0.5 V

Damage Levels 1V

rms

for a calibrated output level.

rms

See also, “I/Q Modulation” on page 121.

17. Q Input (vector models only)

Connector Type: female BNC Impedance: 50Ω

Signal An externally supplied analog, quadrature- phase component of I/Q modulation.

The signal level is = 0.5 V

Damage Levels 1V

See also, “I/Q Modulation” on page 121.

Agilent N5181A/82AMXG Signal Generators User’sGuide 5

rms

for a calibrated output level.

rms

Signal Generator Overview Front Panel Overview

18. Knob

Rotating the knob increases or decreases a numeric value, or moves the highlight to the next digit, character, or item in a list. See also, “Front Panel Knob Resolution” on page 17.

19. Incr Set

This hardkey enables you to set the increment value of the currently active function. The increment value also affects how much each turn of the knob changes an active function’s value, according to the knob’s current ratio setting (see “Front Panel Knob Resolution” on page 17).

20. Return

This hardkey enables you to retrace key presses. In a menu with more than one level, the Return key

returns to the prior menu page.

21. More and LED

When a menu contains more softkey labels than can be displayed, the More LED lights and a More message displays below the labels. To display the next group of labels, press the More hardkey.

22. Power Switch and LEDs

This switch selects the standby mode or the power on mode. In the standby position, the yellow LED lights and all signal generator functions deactivate. The signal generator remains connected to the line power, and some power is consumed by some internal circuits. In the on position, the green LED lights and the signal generator functions activate.

6 A gilent N5181A/ 82A MXG SignalGeneratorsUser’s Guide

Front Panel Display

Signal Generator Overview

Front Panel Display

1. Active Function Area

5. Error Message Area

2. Frequency Area

3. Annunciators

6. T ext Area

7. Softkey Label Area

4. Amplitude Area

Scroll Bar

If there is more text than can be displayed on one screen, a scroll bar appears here Use the Page Up and Page Down keys to scroll through the text.

1. Active Function Area

This area displays the currently active function. For example, if frequency is the active function, the current frequency setting appears. If the currently active function has an increment value associated with it, that value also appears.

2. Frequency Area

This area displays the current frequency setting.

3. Annunciators

Annunciators show the status of some of the signal generator functions, and indicate error conditions. An annunciator position may be used by more than one annunciator; in this case, only one of the functions sharing a given position can be active at a given time.

This annunciator appears when . . .

ΦM Phase modula tion is on. If you tur n frequency modulation on, the FM annunciator replaces ΦM. ARB The ARB generator is on. ALC OFF The ALC circuit is disabled. The UNLEVEL annunciator appears in the same position if the ALC is enabled and

AM Amplitude modulation is on. ARMED A sweep has been initiated and the signal generator is waiting for the sweep trigger event. ATTNHOLD The attenuator hold function is on. When this function is on, the attenuator is held at its current setting. DETHTR The ALC detector heater is not up to temperature. To meet ALC specifications the heater must be at

AWGN Real Time I/Q Baseband additive white Gaussian noise is on.

Agilent N5181A/82AMXG Signal Generators User’sGuide 7

is unable to maintain the output level.

temperature.

Signal Generator Overview Front Panel Display

This annunciator appears when . . .

DIGBUS The digital bus is in use. ERR An error message is placed in the error queue. This annunciator does not turn off until you either view all of

EXTREF An external frequency reference is applied. FM Frequency modulation is on. If you turn phase modulation on, the ΦM annunciator replaces FM. I/Q I/Q vector modulation is on. L The signal generator is in listener mode and is receiving information or commands over the GPIB, USB, or

MULT A frequency multiplier is set (see “Setting a Frequency Multiplier” on page 51). OFFS An output offset is set (see “Setting an Output Offset” on page 49). PULSE Pulse modulation is on. R The signal generator is remotely controlled over the GPIB, USB, or VXI- 11/Sockets (LAN) interface. REF An output reference is set (see “Setting an Output Reference” on page 50). S The signal generator has generated a service request (SRQ) over the GPIB, USB, or VXI- 11/Sockets (LAN)

SWEEP The signal generator is currently sweeping in list or step mode. SWMAN The signal generator is in manual sweep mode. T The signal generator is in talker mode and is transmitting information over the GPIB, USB, or VXI- 11/Sockets

UNLEVEL The signal generator is unable to maint ain the correct output level. This is not necessarily an indication of

UNLOCK Any of the phase locked loops cannot maintain phase lock. To determine which loop is unlocked, examine the

WINIT The signal generator is waiting for you to initiate a single sweep.

the error messages or clear the error queue (see “Reading Error Messages” on page 42).

VXI- 11/Sockets (LAN) interface.

interface.

(LAN) interface.

instrument failure; unleveled conditions can occur during normal operation. Another annunciator, ALC OFF, appears in the same position when the ALC circuit is disabled (see ALC OFF, above).

error messages (see “Reading Error Messages” on page 42).

4. Amplitude Area

This area displays the current output power level setting.

5. Error Message Area

This area displays abbreviated error messages. If multiple messages occur, only the most recent message remains displayed. See “Reading Error Messages” on page 42.

6. Text Area

This area displays signal generator status information, such as the modulation status, and other information such as sweep lists and file catalogs. This area also enables you to perform functions such as managing information (entering information, and displaying or deleting files).

7. Softkey Label Area

This area displays labels that define the function of the softkeys located immediately to the right of the display. Softkey labels change, depending on the function selected.

8 A gilent N5181A/ 82A MXG SignalGeneratorsUser’s Guide

Rear Panel Overview

Signal Generator Overview

Rear Panel Overvi ew

Digital Modulation Connectors (vector models only) on page 12

Option 1EM

only

See page 5

3. AM

2. SWEEP OUT

4. FM

6. TRIG IN

5. PULSE

7. TRIG OUT

9. 10 MHz OUT

8. REF IN

1. AC Power Receptacle

10. GPIB

11. LAN

12. Device USB

1. AC Power Receptacle

The AC power cord receptacle accepts a three- pronged AC power cord that is supplied with the signal generator. For details on line setting requirements and the power cord, see the Installation Guide.

2. SWEEP OUT

Connector female BNC

Can drive 2 kΩ.

Signal Voltage range: 0 to +10V, regardless of sweep width

In swept mode: beginning of sweep = 0V; end of sweep = +10V In CW mode: no output

This is a multiple use connector. For signal routing selections, see pages 33 and 57.

Impedance <1Ω

3. AM

Connector female BNC Impedance nominally 50Ω Signal An externally supplied ±1V

Damage Levels 5V

Agilent N5181A/82AMXG Signal Generators User’sGuide 9

and 10V

rms

signal that produces the indicated depth.

Signal Generator Overview Rear Panel Overvi ew

4. FM

Connector female BNC Impedance nominally 50Ω Signal An externally supplied ±1V

Damage Levels 5V

and 10V

rms

signal that produces the indicated deviation

5. PULSE

Connector female BNC Impedance nominally 50Ω Signal Externally supplied: +1V = on; 0V = off

Damage Levels 5V

and 10V

rms

6. TRIG IN

Connector female BNC Impedance high Z

Signal An externally supplied TTL or CMOS signal for triggering operations, such as

point-to-point in manual sweep mode or an LF sweep in external sweep mode. Triggering can occur on either the positive or negative edge.

Damage Levels ≤ −0.5V and ≥ +5.5V

7. TRIG OUT

Connector female BNC Impedance nominally 50Ω

Signal A TTL signal that is high at the start of a dwell sequence, or when waiting for the point

trigger in manual sweep mode. It is low when the dwell is over, or when the point trigger is received. The logic polarity can be reversed.

This is a multiple use connector. For signal routing selections, see pages 33 and 57.

8. REF IN

Connector female BNC Impedance nominally 50Ω Signal An externally supplied −3.5 to +20 dBm signal from a timebase reference that is

within ±1 ppm.

In its factory default mode, the signal generator can detect a valid reference signal at this connector and automatically switch from internal to external reference operation. See “Presetting the Signal

Generator” on page 23. With Option 1ER (flexible reference input), you must explicitly tell the signal

generator the external reference frequency you wish to use; enter the information through the front panel or over the remote interface.

10 Agilent N5181A/82A MXG Signal Generators User’s Guide

Signal Generator Overview

Rear Panel Overvi ew

9. 10 MHz OUT

Connector female BNC Impedance nominally 50Ω

Signal A nominal signal level greater than 4 dBm.

10. GPIB

This connector enables communication with compatible devices such as external controllers, and is one of three connectors available to remotely control the signal generator (see also 11. LAN and

12. Device USB).

11. LAN

The signal generator supports local area network (LAN) based communication through this connector, which enables a LAN- connected computer to remotely program the signal generator. The LAN

interface is LXI class C compliant; it does not support auto−MDIX. The signal generator is limited to

100 meters on a single cable (100Base-T). For more information on the LAN, refer to the Programming Guide.

12. Device USB

Connector Mini- B

USB Protocol Version 2.0

Use this universal serial bus (USB) connector to connect a PC to remotely control the signal generator.

Agilent N5181A/82AMXGSignal Generators User’sGuide 11

Signal Generator Overview

Rear Panel Overvi ew

Digital Modulation Connectors (vector models only)

I OUT, QOUT, OUT, OUT

Connector Type: female BNC Impedance: 50Ω

DC- coupled

Signal

I OUT The analog, in-phase component of I/Q modulation from the internal baseband generator.

Q OUT The analog, quadrature-phase component of I/Q modulation from the internal baseband

OUT

Damage Levels > 1 Vrms DC Origin Offset typically <10 mV

Output Signal Levels into a 50Ω Load

Balanced signals are signals present in two separate conductors that are symmetrical relative to ground, and are opposite in polarity (180degrees out of phase).

generator.

Used in conjunction with the I OUT connector to provide a balanced

Used in conjunction with the Q OUT connector to provide a balanced

• 0.5V

• 0.69V

• 0.71V

• Typically 1V

, typical, corresponds to one unit length of the I/Q vector

(2.84 dB), typical, maximum crest factor for peaks for π/4 DQPSK, alpha = 0.5

(3.08 dB), typical, maximum crest factor for peaks for π/4 DQPSK, alpha = 0.35

maximum

p- p

baseband stimulus.

EXT CLOCK

Connector female BNC Impedance nominally 50Ω

Signal An externally supplied TTL or CMOS bit clock signal where the rising edge aligns with the

beginning data bit. The falling edge is used to clock external signals. This signal is used with digital modulation applications.

Damage Levels > +8 and < −4V Maximum Clock Rate 50 MHz

EVENT 1

Connector female BNC Impedance: nominally 50Ω

Signal A pulse that can be used to trigger the start of a data pattern, frame, or timeslot.

Adjustable to ± one timeslot; resolution = one bit

Markers

Each Arb- based waveform point has a marker on/off condition associated with it. Marker 1 level = +3.3V CMOS high (positive polarity selected); –3.3V CMOS low (negative polarity selected). Output on this connector occurs whenever Marker 1 is on in an Arb- based waveform (see

“Using Waveform Markers” on page 82).

Damage Levels >+8 and <−4V

12 Agilent N5181A/82A MXG Signal Generators User’s Guide

Signal Generator Overview

A A

E M

A T r

T c

T D

Rear Panel Overvi ew

PAT TRIG IN

Connector female BNC Impedance: nominally 50Ω

Signal A TTL/CMOS low to TTL/CMOS high, or TTL/CMOS high to TTL/CMOS low edge trigger.

The input to this connector triggers the internal digital modulation pattern generator to start a single pattern output or to stop and re-synchronize a pattern that is being continuously output. To synchronize the trigger with the data bit clock, the trigger edge is latched, then sampled during the falling edge of the internal data bit clock. This is the external trigger for all ARB waveform generator triggers.

Minimum Trigger Input Pulse Width (high or low) = 100 ns

Minimum Trigger Delay (trigger edge to first bit of frame) = 1.5 to 2.5 bit clock periods

Damage Levels > +8 and < −4V

DIGITAL BUS I/O

This is a proprietary bus used by Agilent Technologies signal creation software. This connector is not operational for general purpose use. Signals are present only when a signal creation software option is installed (for details, refer to http://www.agilent.com/find/signalcreation).

AUX I/O

Pin 1 = Event 1 Pin 2 = Event 2 Pin 3 = Event 3

View looking into rear panel female 50-pin connector

2650

vent 1, 2, 3, and 4 (pins 1 − 4)

pulse that can be used to trigger the start of a data pattern, frame, or timeslot. djustable to ± one timeslot; resolution = one bit

arkers

ach Arb-based waveform point has a marker on/off condition associated with it.

arker level = +3.3V CMOS high (positive polarity selected); –3.3V CMOS low (negative polarity selected).

utput on these pins occurs whenever the corresponding marker is on in an Arb-based waveform (see “Using Waveform Markers” on

age 82).

ample Rate Clock Out (pin 5)

his output is used with an internal baseband generator. This pin relays a CMOS bit clock signal for synchronizing serial data.

amage levels: > +5.5 and < −0.5V.

att Trig In 2 (pin 6)

TTL/CMOS low to TTL/CMOS high, or TTL/CMOS high to TTL/CMOS low edge trigger. he input to this connector triggers the internal digital modulation pattern generator to start a single pattern output or to stop and

e-synchronize a pattern that is being continuously output.

o synchronize the trigger with the data bit clock, the trigger edge is latched, then sampled during the falling edge of the internal data bit lock.

his is an external trigger for all ARB waveform generator triggers. Minimum pulse width = 100 ns. Damage levels: > +5.5 and < −0.5V.

Agilent N5181A/82AMXGSignal Generators User’sGuide 13

Pin 4 = Event 4 Pin 5 = Sample Rate Clock Ou Pin 6 = Patt Trig In 2

Pins 7–25 = Reserved* Pins 26–50 = Ground

*Future Capability

Signal Generator Overview Rear Panel Overvi ew

14 Agilent N5181A/82A MXG Signal Generators User’s Guide

2 Setting Preferences & Enabling Options

The Utility menu provides access to both user and remote operation preferences, and to the menus in which you can enable instrument options.

Remote Operation

Configuring the GPIB Interface on page 19 Configuring the LAN Interface on page 20 Enabling LAN Services: Browser, Sockets, and VXI-11 on page 20

User Preferences

Front Panel Knob Resolution on page 17 Setting Time and Date on page 18

page 16

page 17

Enabling an Option on page 21

Upgrading Firmware on page 18

Agilent N5181A/82AMXGSignal Generators User’sGuide 15

Setting Preferences & Ena b lin g Opt ion s

User Prefere nc es

User Preferences

From the Utility menu, you can set the following user preferences:

• Display Settings, below

• Power On and Preset on page 17

• Front Panel Knob Resolution on page 17

Display Settings

See also, Using the Secure Display (Option 006 Only) on page

Utility > Display >

For details on each key, use key help as described on page23.

Range: 15—100

Range: 35—55

Light Only: turns the display light off, leaving the text visible at a low intensity. Light & Text: turns the display light and the text off.

If the display remains unchanged for long periods of time, use this mode to prevent the text from burning the display.

Range: 1—12 hours, in 1 hour increments

When on, commands executed through the remote control bus update the signal generator display accordingly.

page 137

Dark text on a ligh background.

Light text on a dar background.

Bright without col

NOTE With both brightness and contrast set to minimum, the display may be too dark to see the

softkeys. If this happens, use the figure above to locate the brightness and contrast softkeys and adjust their values so that you can see the display.

16 Agilent N5181A/82A MXG Signal Generators User’s Guide

Power On and Preset

U I

F a

tility > Power On/Preset >

Restores persistent settings (those unaffected by a power cycle, preset, or recall)

Setting Preferences & Enabling Options

Select the GPIB language desired after a preset. See also, the Programming Gu ide and the SCPI Referenc

Available only when 8648 is either the selected preset language, o the selected GPIB remote language (see page 19).

User Preferences

ote

o define a user preset, set the instrument up as desired and press User Preset > Save User Preset.

Front Panel Knob Resolution

tility >

nstrument Adjustments >

or details on each key, use key help

s described on page 23.

Agilent N5181A/82AMXGSignal Generators User’sGuide 17

Makes the increment value of the current function the active entry.

The increment value and the step/knob ratio determine how much each turn of the knob changes the active function value.

For example, if the increment value of the active function is 10 dB and th step/knob ratio is 50 to 1, each turn of the knob changes the active function by 0.2 dB (1/50th of 10 dB).

To change the amount for each turn of the knob, modify the increment value, the step/knob ratio, or both.

Setting Preferences & Ena b lin g Opt ion s

U I

Upgrading Firmware

Setting Time and Date

CAUTION

Changing the time or date can adversely affect the signal

generator’s ability to use time−based licenses, even if a time−based

license is not installed when you change the time or date.

tility >

nstrument Adjustments >

The signal generator’s firmware tracks the time and date, and uses the latest date and time that has been set as its time/date reference point.

Setting the Time or Date Forward

If you set the time or date forward, be aware that you are using up any installed time- based licenses, and that you are resetting the signal generator’s time/date reference point. When you set a new time or date that is later than the signal generator’s current reference point, that date becomes the new reference point. If you then set the date back, you run the risk described in the next section.

Original time/date reference point

Time

New time/date reference point

Setting the Time or Date Backward

When you set the time back, the signal generator notes that the time has moved back from the reference point (the latest date that has been set). If you set the time back more than approximately 25 hours, you disable the signal generator’s ability to use time- based licenses, even if there is no license installed at the time that you set the time back. In this case, you can reenable the signal generator’s ability to use time- based licenses by returning the date to within 25 hours prior to the the reference point, or to anytime after the reference point.

Current time/date reference point

Time

Point at which the signal generator can no longer use time-based licenses.

> 25 hours

If you find you must set the date backward more than approximately 25 hours (when, for example, the time is mistakenly set ahead) and you wish to use time- based licenses, you must contact Agilent Technologies for assistance (see page 151).

Upgrading Firmware

For information on new firmware releases, go to http://www.agilent.com/find/upgradeassistant.

18 Agilent N5181A/82A MXG Signal Generators User’s Guide

Setting Preferences & Enabling Options

Remote Operat i on Preferences

Remote Operation Preferences

For details on operating the signal generator remotely, refer to the Programming Guide.

Below

page 20

NOTES

USB is also available. It is not shown in the menu because it requires no configuration.

For details on using the instrument remotely, see the Programming Guid

Configuring the GPIB Interface

Utility > I/O Config >

Select the desired GPIB languag

For details on each key, use key help as described on page 23.

Agilent N5181A/82AMXGSignal Generators User’sGuide 19

Setting Preferences & Ena b lin g Opt ion s

F a

Remote Operation P ref erences

Configuring the LAN Interface

tility > I/O Config >

See page 20

NOTES

Use a 100Base-T LAN cable to connect the signal generator to the LAN.

Use a crossover cable to connect the signal generator directly to a PC.

For details on using the instrument remotely, see the Programming Guid e.

Listed in the

Programming Guide

Enabling LAN Services : Browser, Sockets, and VXI-11

Utility > I/O Config >

or details on each key, use key help s described on page23.

20 Agilent N5181A/82A MXG Signal Generators User’s Guide

Enable remote (browser) access to the instrument’s file system.

Use a browser to control the signal generator.

Enabling an Option

There are two ways to enable an option:

• Use the License Manager software utility:

1. Download the utility from www.agilent.com/find/LicenseManager

2. Run the utility and follow the prompts.

• Use SCPI commands, as described in the Programming Guide.

Viewing Options and Licenses

Utility > Instrument Info >

Setting Preferences & Enabling Options

Enabling an Option

Service Software Licenses appear here.

Waveform licenses from some

Instrument options appear here. A check mark means that an option is enabled.

Agilent N5181A/82AMXGSignal Generators User’sGuide 21

Signal Studio applications appear here.

For details on each key, use key help as described on page23.

Setting Preferences & Ena b lin g Opt ion s Enabling an Option

22 Agilent N5181A/82A MXG Signal Generators User’s Guide

3 Basic Operation

This chapter introduces fundamental front panel operation. For information on remote operation, refer to the Programming Guide.

• Presetting the Signal Generator, below

• Viewing Key Descriptions, below

• Entering and Editing Numbers and Text on page 24

• Setting Frequency and Power (Amplitude) on page 26

• Configuring a Swept Output on page 27

• Modulating the Carrier Signal on page 34

• Viewing, Saving, and Recalling Data on page 35

• Reading Error Messages on page 42

Presetting the Signal Generator

To return the signal generator to a known state, press either Preset or User Preset. Preset is the factory preset; User Preset is a custom preset* (see also, page 17). To reset persistent settings (those unaffected by preset, user preset, or power cycle),

press: Utility > Power On/Preset > Restore Sy st em Defau lts.

*You can create more than one user preset by giving each saved state file a different name (see Figure 3-6 on page 40).

Viewing Key Descriptions

The Help hardkey enables you to display a description of any hardkey or softkey. To display help text:

1. Press Help.

2. Press the desired key. The help displays and the key’s normal function does not execute.

Agilent N5181A/82AMXGSignal Generators User’sGuide 23

Basic Operation

Entering and Editing Numbers and Text

Entering Numbers and Moving the Cursor

Use the number keys and decimal point to enter numeric data.

Up/down arrow keys increase/decrease a selected (highlighted) numeric value, and move the cursor vertically

Page up/down keys move tables of data up and down within the display area

Left/right arrow keys move the cursor horizontally.

Use the Select hardkey to choose part of an entry, as when entering alpha characters. In some menus, the equivalent to the

T o sp ecify a nega tive valu e, enter the negative sign either before or after

the numeric value (this key is a toggle).

Backspace moves the cursor to the left, deleting characters as it goes.

For details on each key, see page 23.

Enter softkey.

Select key also acts as a terminator, and is

Note: Rotating the knob increases or

decreases a numeric value, changes a highlighted digit or character, or steps through lists or items in a row.

See also, Front Panel Knob Resolution on page 1

Entering Alpha Characters

Note: File names are limited to 25 characters.

Data entry softkeys appear in various menus. If their meaning is not clear in context, use the help key (described on page 23) to display an explanation. Use the softkey next to the alpha table for help on the table.

Selecting data that accepts alpha characters, displays one of the menus shown at right.

Use the arrow keys or knob to

to move the cursor within the active value rather than within the alpha table, turn the alpha table off.

highlight the desired letter, then

press the Select hardkey (or the

softkey next to the alpha table).

Add/edit comments for saved instrument state files (see page 38).

To correct errors, use Bk Sp or Clear Text.

To terminate the entry, press the Enter softkey.

A subset of this menu appears for hexadecimal characters. The character menu displays only the letters A through F (use the numeric keypad for other values).

24 Agilent N5181A/82A MXG Signal Generators User’s Guide

Entering and Editing Numbers and Text

Basic Operation

Example: Using a Table Editor

Table editors simplify configuration tasks. The following procedure describes basic table editor functionality using the List Mode Values table editor.

1. Preset the signal generator: Press Preset.

2. Open the table editor: Press Sweep > More > Config ure List Sweep.

The signal generator displays the editor shown in the following figure.

Active Function Area

Displays the active item as you edit it.

T a ble Editor Name

Current / Total Number of Pages

Highlighting indicates the selected item. To make this the active (editable) item, either press Select, or simply enter the desired value.

(vector models only)

Table Items

Table items are also called data fields.

Cursor

T a ble Editor Softkeys

Used to load, navigate, modify, and store table item values. For details on each key, use the key help: Press the Help hardkey and then the desired key.

Indicates that another menu is available; to display the second menu, press More.

3. Highlight the desired item: use the arrow keys or the knob to move the cursor.

4. (Optional) Display the selected item in the active function area: Press Select.

5. Modify the value:

• If the value is displayed in the active function area, use the knob, arrow keys, or numeric keypad to modify the value.

• If the value is not displayed in the active function area, use the numeric keypad to enter the desired value (which then appears in the active function area).

6. Terminate the entry:

• If available, press the desired units.

• If units are not displayed, press either Enter (if available) or Select.

The modified item is displayed in the table.

Agilent N5181A/82AMXGSignal Generators User’sGuide 25

Basic Operation Setting Frequency and Power (Amplitude)

Setting Frequency and Power (Amplitude)

Figure 3-1 Frequency and Amplitude Softkeys

See

page 47

page 44

Option 1ER only

To display the next menu, press More.

For details on each key, use key help as described on page23.

Example: Configuring a 700 MHz, −20 dBm Continuous Wave Output

1. Preset the signal generator.

The signal generator displays its maximum specified frequency and minimum power level (the front panel display areas are shown on page 7).

2. Set the frequency to 700 MHz: Press Freq > 700 > MHz.

The signal generator displays 700 MHz in both the FREQUENCY area of the display and the active entry area.

3. Set the amplitude to −20 dBm: Press Amptd > –20 > dBm. The display changes to −20 dBm in the AMPLITUDE area of the display, and the amplitude value

becomes the active entry. Amplitude remains the active function until you press another function key.

4. Turn on the RF Output: Press RF On/Off. The RF Output LED lights, and a 700 MHz, −20 dBm CW signal is available at the RF OUTPUT

connector.

26 Agilent N5181A/82A MXG Signal Generators User’s Guide

Configuring a Swept Output

Basic Operation

Configuring a Swept Output

The signal generator has two methods of sweeping through a set of frequency and amplitude points:

Step sweep (page 28) provides a linear or logarithmic progression from one selected frequency, or amplitude, or both to another, pausing at linearly or logarithmically spaced points (steps) along the sweep. The sweep can progress forward, backward, or manually.

List sweep (page 29) enables you to enter frequencies and amplitudes at unequal intervals, in nonlinear ascending, descending, or random order. List sweep also enables you to copy the current step sweep values, include an Arb waveform in a sweep (on a vector instrument), and save list sweep data in the file catalog (page 37).

Figure 3-2 Sweep Softkeys

During a frequency sweep, the CW frequency does not display; for an amplitude sweep, the amplitude does not display; for a frequency and amplitude sweep, neither frequency nor amplitude displays.

The selected sweep type determines the displayed parameter.

Progress Bar: very fast sweeps can appear to sweep randomly or backward

See page 28

Available when

Sweep Type = List

Down sweeps from

stop to start frequency/amplitude

Up sweeps from sta to stop frequency/amplitude

See page 33

See

page 29

See

page 33

or details on each key, use key help as described on page23.

Sweep without waiting for a trigger at each point. Point Trigger pauses for the dwel l time prior to the first sweep.

Trigger on a remote command.

Apply a TTL/CMOS signal to the Trigger In connector.

Periodically issue a trigger event to whatever selects it as a source.

Using timer trigger with single sweep results in a delay pr ior to the first sweep.

Agilent N5181A/82AMXGSignal Generators User’sGuide 27

Basic Operation

ly.

For details on each key, use key help

Configuring a Swept Output

Step Sweep

Step sweep provides a linear or logarithmic progression from one selected frequency, or amplitude, or both, to another, pausing at linearly or logarithmically spaced points (steps) along the sweep. The

sweep can progress forward, backward, or manually.

as described on page 23.

Dwell Time = the time that the signal is settled and you can mak a measurement before the sweep moves to the next point.

(Point-to-point time is the sum of the value set for the dwell plu processing time, switching time, and settling time.)

Step Sweep and List Sweep dwell times are set indep enden t

Lin = steps equally spaced over the sweep; the output changes

linearly.

Log = step spacing increases logarithmically over the sweep; the

output changes exponentially.

Example: Configuring a Continuous, Linear Step Sw eep

Output: A signal that continuously sweeps from 500 to 600 MHz and from −20 to 0 dBm, with a

dwell time of 500 ms at each of six equally−spaced points.

1. Preset the instrument and open the Sweep/List menu: Press Preset > SWEEP.

Because continuous is the default sweep repeat selection, and linear is the default step spacing selection, you do not need to set these parameters.

2. Open the step sweep menu: Press Configure Step Sweep.

3. Set the following parameters:

Start frequency 500 MHz: Press Freq Start > 500 > MHz Stop frequency 600 MHz: Press Freq Stop > 600 > MHz Amplitude at the beginning of the sweep, −20 dBm: Press Amptd Start >

−20 > dBm

Amplitude at the end of the sweep, 0 dBm: Press Amptd Stop > 0 > dBm. 6 sweep points: Press # Points > 6 > Enter Dwell time at each point, 500 milliseconds: Press More > Step Dwell > 500 > msec

4. Sweep both frequency and amplitude: Press Return > Return > Sweep > Freq Off On > Amptd Off On.

A continuous sweep begins, from the start frequency/amplitude to the stop frequency/amplitude. The SWEEP annunciator displays, both the CW frequency and the amplitude display blank (indicating that both are sweeping), and the progress bar shows the sweep progress.

5. Turn the RF output on: Press RF On/Off.

The RF LED lights, and the continuous sweep is available at the RF Output connector.

28 Agilent N5181A/82A MXG Signal Generators User’s Guide

Configuring a Swept Output

For details on each key, use key help

Basic Operation

List Sweep

List sweep enables you to enter frequencies and amplitudes at unequal intervals in nonlinear ascending, descending, or random order. List sweep also enables you to copy the current step sweep values, include a waveform in a sweep (on a vector instrument), and save list sweep data in the file catalog (page 37). Dwell time is editable at each point.

Figure 3-3 List Sweep Configuration Softkeys and Display

as described on page 23.

Displays the selected sweep type parameters (see page 30)

See page 28

Available only on vector models, and only when Sweep Type = List.

Available only when waveform entry is selected

Each line defines the corresponding point in the sweep. For example, line 1 defines point 1.

The selected sweep determines which dwell time the signal generator uses. Step Sweep dwell time is the same at each point; List Sweep dwell time can be different at each point.

Dwell Time = the time that the signal is settled and you can make a measurement before the sweep moves to the next point.

Point-to-Point Time = the sum of the value set for the dwell plus processing time, switching time, and settling time.

See page 33

Vector models only

see page 30

Agilent N5181A/82AMXGSignal Generators User’sGuide 29

Basic Operation Configuring a Swept Output

Example: Configur ing a List Sweep Using Step Sweep Data

1. Set up the desired step sweep, but do not turn the sweep on. This example uses the step sweep configured on page 28.

2. In the SWEEP menu, change the sweep type to list:

Press SWEEP > Sweep Type List Step to highlight List.

The display shows sweep list parameters, as shown below.

3. Open the List Sweep menu: Press More > Configure List Sweep.

4. Clear any previously set values from the menu and load the points defined in the step sweep into

the list: Press More > Preset List > Preset with Step Sweep > Confirm Preset.

The display updates with the values loaded from the step sweep, as shown.

Vector Mo del s:

Presetting the list clears any previously selected waveforms.

For information on selecting a list sweep waveform, see Example:

Editing List Sweep

Waveforms are available only on vector models.

Poin ts on page 31.

5. Sweep frequency and amplitude: Press SWEEP (hardkey) > Sweep > Freq Off On > Amptd Off On.

Setting the sweep turns on the sweep function; a continuous sweep begins. On the display, the SWEEP annunciator appears, and the progress bar shows the progression of the sweep.

6. If not already on, turn the RF output on: Press RF On/Off.

The RF Output LED lights, and a continuous sweep is available at the RF OUTPUT connector.

30 Agilent N5181A/82A MXG Signal Generators User’s Guide

Configuring a Swept Output

Basic Operation

Example: Editing List Sweep Points

If you are not familiar with table editors, refer to page 25.

1. Create the desired list sweep. This example uses the list sweep created in the previous example.

2. If sweep is on, turn it off. Editing list sweep parameters with sweep on can generate an error.

3. Set the sweep type to list: Press SWEEP > Sweep Type List Step to highlight List.

4. In the List Mode Values table editor, change the point 1 dwell time (defined in row 1) to 100 ms:

a. Press More > Configure List Sweep.

b. Highlight the point 1 dwell time.

c. Press 100 > msec.

The next item in the table (the frequency value for point 2) highlights.

5. Change the selected frequency value to 445 MHz: Press 445 > MHz.

6. Add a new point between points 4 and 5: Highlight any entry in row 4 and press Insert Row.

This places a copy of row 4 below row 4, creating a new point 5, and renumbers subsequent rows.

7. Shift frequency values down one row, beginning at point 5: Highlight the frequency entry in row

5, then press More > InsertItem.

This shifts the original frequency values for rows 5 and 6 down one row, and creates an entry for row 8 that contains only a frequency value (the power and dwell time entries do not shift down).

8. Change the still- active frequency value in row 5 to 590 MHz: Press 590 > MHz. The power in row 5

is now the active parameter.

9. Insert a new power value (−2.5 dBm) for point 5, and shift down the original power values for

points 5 and 6 by one row: Press Insert Item >

−2.5 > dBm.

10. To complete the entry for point 8, insert a duplicate of the point 7 dwell time by shifting a copy

of the existing value down: Highlight the dwell time in row 7 and press Insert Item.

11. For an analog instrument, go to step 14. For a vector instrument, continue with step 12.

12. Select a waveform for point 2:

a. Highlight the waveform entry for point 2 and press the More > Select Waveform.

The signal generator displays the available waveforms, as shown in the following example.

Either select a waveform,

select no modulation.

b. Highlight the desired waveform (in this example, SINE_TEST) and press either the Select

hardkey or the Select Waveform softkey.

Agilent N5181A/82AMXGSignal Generators User’sGuide 31

Basic Operation Configuring a Swept Output

13. As desired, repeat step 12 for the remaining points for which you want to select a waveform. The following figure shows an example of how this might look.

The empty entry is equivalent to choosing CW (no modulation).

14. Turn sweep on:

Press Return > Return > Return > Sweep > FreqOff On > AmptdOff On > Waveform Off On.

15. If it is not already on, turn the RF output on:

Press RFOn/Off. The SWEEP annunciator appears on the display, indicating that the signal generator is sweeping,

and the progress bar shows the progression of the sweep.

Example: Using a Single Sweep

1. Set up either a step sweep (page 28) or a list sweep (page 30).

2. In the List/Sweep menu, set the sweep repeat to single:

Press Sweep Repeat Single Cont to highlight Single.

Sweep does not occur until you trigger it. Note that the WINIT annunciator appears on the display, indicating that the sweep is waiting to

be initiated.

3. If not already on, turn the RF output on: Press RF On/Off.

4. Initiate the sweep: Press Single Sweep.

A single repetition of the configured sweep is available at the RF Output connector. As the signal generator sweeps, the SWEEP annunciator replaces WINIT on the display, and the

progress bar shows the progression of the sweep. At the end of the single sweep, there is no progress bar, and the WINIT annunciator replaces

SWEEP.

32 Agilent N5181A/82A MXG Signal Generators User’s Guide

Configuring a Swept Output

Example: Manual Control of Sweep

1. Set up either a step sweep (page 28) or a list sweep (page 30).

2. In the Sweep/List menu, select a parameter to sweep: Press Sweep > parameter.

3. Select manual mode: Press Return > More > Manual Mode Off On.

4. If it is not already on, turn the RF output on: Press RF On/Off.

5. Select the point to output: Press Manu al Point > number > Enter.

6. Use the knob or arrow keys to move from point to point.

Basic Operation

The SWMAN annunciator indicates that the sweep is in manual mode.

When you enter the manual point, the progress bar moves to and stops at the selected point.

Routing Signals

Sweep > More > More > Route Connectors >

The parameters of the selected sweep point define the signal available at the RF Output conn ecto r.

Select the signal that you want routed to each output connector.

For details on each key, use key help as described on page 23.

Agilent N5181A/82AMXGSignal Generators User’sGuide 33

Basic Operation Modulating the Carrier Signal

Modulating the Carrier Signal

To modulate the carrier signal, you must have both

• an active modulation format

and

• modulation of the RF output enabled

Example

1. Preset the signal generator.

2. Turn on AM modulation: Press AM > AM Off On (requires Option UNT).

You can turn on the modulation format before or after setting signal parameters.

The modulation format generates, but does not yet modulate the carrier signal.

Once the signal generates, an annunciator showing the name of the format appears, indicating that a modulation format is active.

3. Enable modulation of the RF output: Press the Mod On/Off key until the LED lights.

If you enable modulation without an active modulation format, the carrier signal does not modulate until you subsequently turn on a modulation format.

Annunciator indicates active AM modulation

AM modulation format on.

A lit LED indicates that any active modulation format can modulate the carrier.

NOTE To turn modulation off, press the Mod On/Off key until the LED turns off.

When the Mod On/Off key is off, the carrier signal is not modulated, even with an active

modulation format.

4. To make the modulated carrier available at the RF output connector, press the RF On/Off key until

the LED lights.

See also: “Using Analog Modulation (Option UNT Only)” on page 53

“Using Pulse Modulation (Option UNU)” on page 57 “I/Q Modulation” on page 121

34 Agilent N5181A/82A MXG Signal Generators User’s Guide

Viewing, Saving, and Recalling Data

Note: Available file types depend on the installed options.

Basic Operation

Viewing, Saving, and Recalling Data

The signal generator enables you to store data as files and view those files in a file catalog. From the File Catalog (shown in Figure 3- 4), you can delete, copy, or rename a stored file.

• Viewing a Stored File on page 36

• Saving and Recalling Data on page 37

Viewing a Stored File

Files Stored in the Signal Generator

1. Press File > Catalog Type > desired catalog.

The files in the catalog appear in alphabetical order. File information includes the file:

•name

•type

•size

• modification date and time

Files Stored on External Media

1. Connect the external media.

The instrument displays the External Media directory.

2. Highlight the USER directory and press Select.

The file directories on the external media appear in alphabetical order, as shown in the following figure.

se the Page Up and Page Down

eys to see the contents of the

SER directory.

36 Agilent N5181A/82A MXG Signal Generators User’s Guide

Viewing, Saving, and Recalling Data

F a

Basic Operation

Saving and Recalling Data

The method of storing and recalling data depends on the data.

• An instrument state file contains instrument settings. For this type of file, use the Save and Recall

hardkeys, shown in Figure 3- 5 on page 38.

• For other types of data, use the Load/Store softkeys (shown below) that are available through the

menu used to create the file.

or details on each key, use key help

s described on page23.

NOTE File names are limited to 25 characters.

Use this menu to enter the file name, as described on page24.

Agilent N5181A/82AMXGSignal Generators User’sGuide 37

Basic Operation

);

For details on each key, use key help

Viewing, Saving, and Recalling Data

Working with Instr ume nt State Files

Figure 3-5 Save and Recall Softkeys

as described on page23.

Instrument settings (states) save to instrument state memory, which is divided into 10 sequences (0 through 9 each sequence comprises 100 registers (00 through 99)

Delete softkeys in the Save and Recall menus enable yo to delete the contents of a specific register, or the content of all sequences in the state file catalog.

The signal generator requires that you confirm a deletion

The following information is not stored in a state file:

System Security Level List Mode Freq Hostname Remot e Language FM Deviation

System Security Level Display List Mode Power IP Address FTP Server PM Deviation

System Security Level State List Mode Dwell Subnet Mask Manual DHCP MAC

Web Server (HTTP) List Mode Sequence Default Gateway VXI- 11 SCPI User Power Correction

Sockets SCPI (TELNET) Display Stat e On/Off ARB Files List Files I/Q Calibration Data

Example: Saving an Instrument State

1. Preset the signal generator and set the following:

• Frequency: 800 MHz • Amplitude: 0 dBm • RF: on

2. (Optional, vector models only) Associate a waveform file with these settings:

a. Press Mode > Dual ARB > Selec t Waveform. b. Highlight the desired file and press Select Waveform. If the file is not listed, you must first

move it from internal or external media to BBG media, see page 71.

3. Select the desired memory sequence (for this example, 1): Press Save > Select Seq > 1 > Enter.

4. Select the desired register (in this example, 01): Press Select Reg > 1 > Save Reg.

If a waveform is currently selected, saving the instrument state also saves the waveform file name.

5. Add a descriptive comment to sequence 1 register 01:

Press Add Comment to Seq[1] Reg[01], enter the comment and press Enter. The comment appears in the Saved States list when you press Recall. If the instrument state has an associated waveform,

entering the waveform name makes it easy to identify which instrument state applies to which waveform.

38 Agilent N5181A/82A MXG Signal Generators User’s Guide

Viewing, Saving, and Recalling Data

Basic Operation

Example: Recalling an Instrument State

1. Preset the signal generator.

2. Press Recall. The Select Seq softkey shows the last sequence used, and the display lists any states stored in the

registers in that sequence; RECALL Reg is the active entry.

3. Select the desired instrument state:

If the desired state is listed in the currently selected sequence, press desired number > Enter. If not, press Press SelectSeq > desired number > Enter > RECALL Reg > desired number > Enter.

Example: Recalling an Instrument State and Associated Waveform File

1. Recall the desired instrument state (see previous example).

2. View the waveform file name recalled with the instrument state: press Mode > Dual ARB.

The name is displayed as the selected waveform. Recalling the instrument state recalls only the waveform name. It does not recreate the waveform file if it was deleted, or load the file into BBG media if it is in internal or external media.

3. Ensure that the desired waveform file exists, and that it is in BBG media (page 71). If the waveform file is not in BBG media, performing the next step generates an error.

4. Turn on the waveform file: Press Mode > Dual ARB > ARB Off On.

Example: Recalling an Instrument State and Associated List File

Recalling an instrument state recalls only the list sweep setup. It does not recall the frequency and/or amplitude values. Because you must load the list file from the file catalog, when you store a list file, be sure to give it a descriptive name (up to 25 characters).

1. Recall the desired instrument state (see previous example).

2. Recall the desired list file:

a. Press Sweep > More > Configure List Sweep > More > Load/Store. b. Highlight the desired file and press Load From Selected File > Confirm Load From File.

Agilent N5181A/82AMXGSignal Generators User’sGuide 39

Basic Operation

Viewing, Saving, and Recalling Data

Moving or Copying a Stored Instrument State

Figure 3-6 Instrument State File Catalog

Sequence Register

User Preset Information

If you rename this file, the signal generator no longer recognizes it as user preset information.

Defining a User Preset Set up the instrument as desired, then press User > Save User Preset.

Creating More than One User Preset

Set up several preset conditions under different names; give the one you wish to use the name

USRPRST. To use a different file, rename the current USRPRST, then give the desired file the

name USRPRST.

A user-created state file’s default name is its memory location.

To move the file, rename it to the desired sequence and register.

Yo u can not give a file the same name as an existing file.

Caution If you rename a state file to something other than a valid sequence/register name, the file does not appear in either the Save or Recall menu.

ote

o define a user preset, set up the instrument as desired and press User > Save User Preset.

To change a comment on a saved instrument state:

1. Press Save

2. Highlight the desired register

3. Press Edit Comment In Seq[n] Reg [nn].

4. Press Re-SAVE Seq[n] Reg[nn].

This overwrites previously saved instrument state settings with the new comment.

40 Agilent N5181A/82A MXG Signal Generators User’s Guide

Selecting Internal or External Media

F E

In the External Media menu (shown below), select the desired storage type.

ile > More >

xternal Media File Manager >

Non-Volatile Storage

Int = Internal Ext =External; if a memory stick is not connected,

non-volatile storage is not available.

Auto = External if present, otherwise internal is used.

Viewing, Saving, and Recalling Data

File Length (including extension) Internal Media: 25 characters External Media: 39 characters

Basic Operation

Save From

Sweep menu Save menu Mode menu Amplitude menu User Preset menu Agilent purchase

Pressing Select with file highlighted...

loads list and starts sweep load instrument state loads and plays waveform loads and applies user flatness loads and executes user preset installs purchased license

Requires confirmation

File Type

List State Waveform User Flatness User Preset License

Extension

.list .state .waveform .uflat .uprst .lic

Using External Media

When you connect storage media to the front panel USB connector, the signal generator displays the menu shown in the figure below, and the message External USB Storage attached. When you disconnect the USB media, the message External USB Storage detached displays. When you open the External Media menu without USB media connected, the signal generator displays the message

External Media Not Detected.

To set the directory that the signal generator will use on the external media:

1. Navigate to the directory. It will display in the path.

2. Press this softkey.

To navigate the directory, use the Select hardkey an the Up Directory softkey.

Deletions, backups, and restores require confirmation.

The signal generator does not format external media, create directories, or change file permissions. Use a computer to perform these operations.

Agilent N5181A/82AMXGSignal Generators User’sGuide 41

Basic Operation Reading Error Messages

Reading Error Messages

If an error condition occurs, the signal generator reports it to both the front panel display error queue and the SCPI (remote interface) error queue. These two queues are viewed and managed

separately; for information on the SCPI error queue, refer to the Programming Guide.

Characteristic Front Panel Display Error Queue

Capacity (#errors) 30

Overflow Handling Drops the oldest error as each new error comes in. Viewing Entries Press: Error > View Next (or Previous) Error Page Clearing the Queue Press: Error > ClearError Queue(s)

Unresolved Erro rs

No Er rors

Errors that must be resolved. For example, unlock.

Re- reported after queue is cleared.

When the queue is empty (every error in the queue has been read, or the queue is cleared), the following message appears in the queue:

No Error Message (s) i n Que ue 0 of 0

Error Message Format

In the front panel display error queue, error messages display on an enumerated (“1 of N”) basis.

Error messages appear in the lower-left corner of the display as they occur.

Error Number

Error Message

Error Desc ription

(May be truncated on the display)

−222 Data out of range; value clipped to lower limit.

Indicates that the user has entered a deviation, depth, or internal source frequency that is beyond the specific limits

Explanation is provided in the Error Message file (see page 148)

The annunciator indicates an unviewed message.

(This is not displayed on the instrument)

new indicates a message generated since messages were last viewed.

Message number and longer description

42 Agilent N5181A/82A MXG Signal Generators User’s Guide

4 Optimizing Performance

Before using this information, you should be familiar with the basic operation of the signal generator. If you are not comfortable with functions such as setting the power level and frequency, refer to

Chapter 3, “Basic Operation,” on page 23 and familiarize yourself with the information in that

chapter.

• Using User Flatness Correction on page 44

• Using Unleveled Operating Modes on page 47

• Using an Output Offset, Reference, or Multiplier on page 49

Agilent N5181A/82AMXGSignal Generators User’sGuide 43

Optimizing Performance

For details on each key, use key help

Using User Flatness Correction

User flatness correction enables you to adjust the RF output amplitude for up to 1601 sequential linearly or arbitrarily spaced frequency points to compensate for external losses in cables, switches, or other devices.

You can create and save individual user flatness correction tables, which enables you to recall different correction arrays for various test setups or frequency ranges (see page 46).

Figure 4-1 User Flatness Correction Softkeys

as described on see page23.

Confirm

Basic Procedure

1. Create a user flatness array: Enter the user flatness correction values.

2. Optionally, save the user flatness correction data.

3. Apply user flatness correction to the RF Output.

44 Agilent N5181A/82A MXG Signal Generators User’s Guide

Optimizing Performance

Using User Flatness Correction

Example: A 500 MHz to 1 GHz Flatn ess Correction Arra y with 10 Correction Values

Create the User Flatness Array

1. Configure the signal generator:

a. Preset the signal generator.

b. Open the User Flatness table editor and preset the cal array:

Press Amptd > More > User Flatness > Configure Cal Array > More > Preset List > Confirm Preset.

c. In the Step Array menu, enter the desired flatness- corrected frequencies:

Press Configure Step Array >

Freq Start > 500 > MHz > Freq Stop > 1 > GHz > # of Points > 10 > Enter

d. Populate the user flatness correction array with the step array configured in the previous

step:

Press Return > Load Cal Array From Step Array > Confirm Load From Step Data.

e. Set the output amplitude to 0 dBm.

f. Turn on the RF output.

2. Connect the power meter to the RF output and manually enter the correction values:

a. Open the User Flatness table editor and highlight the frequency value in row 1:

Press More > User Flatness > Configure Cal Array.

The RF output changes to the frequency value of the table row containing the cursor.

b. Note the value measured by the power meter.

c. Subtract the measured value from 0 dBm

d. Highlight the correction value in row 1.

e. Press Select > the difference calculated in step c > Enter.

The signal generator adjusts the output amplitude based on the correction value entered.

f. If the power meter does not read 0 dBm, adjust the value in step e until it does.

g. Highlight the frequency value in the next row.

h. Repeat steps b through g for this and the remaining rows. The user flatness correction array title displays User Flatness:, without a name, indicating that

the current user flatness correction array data has not been saved to the file catalog.

Agilent N5181A/82AMXGSignal Generators User’sGuide 45

Optimizing Performance Using User Flatness Correction

Optional: Save the User Flatness Correction Data

1. Press Load/Store > Store to File.

2. Enter a file name (for this example, FLATCAL1) and press Enter.

The user flatness correction array file is now stored in the file catalog as a UFLT file. Any user flatness correction files saved to the catalog can be recalled, loaded into the correction array, and applied to the RF output to satisfy specific RF output flatness requirements.

3. Press Return.

Enable the Flatness Correction at the RF Output

• Press Return > Flatness Off On.

The UF annunciator appears in the AMPLITUDE area of the display, and the correction data in the array is applied to the RF output.

Recalling and Applying a User Flatness Correction Array

The following example assumes that a user flatness correction array has been created and stored. If not, perform the Example: A 500 MHz to 1 GHz Flatness Correction Array with 10 Correction

Val ues on page 45.

1. Preset the signal generator.

2. Recall the desired User Flatness Correction file:

a. Press AMPTD > More > User Flatness > Configure Cal Array > More > Preset List > Confirm Preset. b. Press More > Load/Store.

c. Highlight the desired file.

d. Populate the user flatness correction array with the data contained in the selected file:

Press Load From Selected File > Confirm Load From File. The user flatness correction array title displays User Flatness: Name of File.

3. Apply the correction data in the array to the RF output: Press Return > Flatness Off On.

46 Agilent N5181A/82A MXG Signal Generators User’s Guide

Using Unleveled Operating Modes

Figure4-2 Power Search and ALC Off Softkeys

Available only when ALC = Off

Available only when Power Search = Span

Available only when Power Search = Span, and Span Type = User

Using Unleveled Operating Modes

Auto: The calibration routine executes whenever output frequency or amplitude changes.

Span: Pressing Do Power Search executes the power search calibration routine once over a selected frequency range.

The corrections are stored and used whenever you tune the signal generator to within the calibrated frequency range.

Optimizing Performance

For details on each key, use key help as described on see page23.

ALC Off Mode

Turning ALC off deactivates the signal generator’s automatic leveling circuitry, enabling you to measure the output at a specific point in a test setup and adjust as required for the desired power level at that point. Turning ALC off is useful when the modulation consists of very narrow pulses that are below the pulse width specification of the ALC, or when the modulation consists of slow amplitude variations that the automatic leveling would remove.

1. Preset the signal generator.

2. Set the desired frequency.

3. Set the desired amplitude.

4. Connect the power meter to the point at which you want a specific power level.

5. Turn the RF output on.

6. Deactivate the signal generator’s automatic leveling control: Press AMPTD > ALC Off On to

highlight Off.

7. Adjust the signal generator’s amplitude until the power meter measures the desired level.

Agilent N5181A/82AMXGSignal Generators User’sGuide 47

Optimizing Performance Using Unleveled Operating Modes

Power Search Mo de

Refer to Figure 4-2 on page 47. Power search executes a routine that temporarily activates the ALC, calibrates the power of the current RF output, and then disconnects the ALC circuitry.

NOTE For the power search routine to execute, RF must be on and ALC must be off.

Example: Automatic Power S earch

1. Preset the signal generator.

2. Set the desired frequency.

3. Set the desired amplitude.

4. Turn the RF output on.

5. Deactivate the signal generator’s automatic leveling control:

Press AMPTD > ALC Off On to highlight Off

Deactivating the signal generator’s automatic leveling control is a significant instrument change that automatically initiates a power search.

When set to Auto, power search automatically executes when a significant instrument setting changes. The Do Power Search feature enables you to execute a power search to compensate for other changes, such as temperature drift or a change in the external input.

48 Agilent N5181A/82A MXG Signal Generators User’s Guide

Using an Output Offset, Reference, or Multiplier

Optimizing Performance

Using an Output Offset, Reference, or Multiplier

Setting an Output Offset

Using an output offset, the signal generator can output a frequency or amplitude that is offset (positive or negative) from the entered value.

RF Output = entered value − offset value

Displayed Value = output frequency + offset value

To se t an offset:

• Frequency: Press Freq > Freq Offset > offset value > frequency unit.

• Amplitude: Press Amptd > More > Amptd Offset > offset value > dB.

Indicates that an offset is on

Examples

Parameter

Entered (and displayed) Value: 300 MHz 300 MHz 2 GHz The entered value must be positive. Offset: 50 MHz −50 MHz −1 GHz An offset value can be positive or negative.

Output Frequency: 250 MHz 350 MHz 3 GHz

Example#1Example#2Example

Comments

The signal generator alerts you if the output frequency or amplitude is out of range.

When using the signal generator as a local oscillator (LO), you can use the offset to display the frequency of interest, as illustrated below:

Antenna tuned to 1321 MHz

RF Amplifier

Mixer

Output Frequency = 1000 MHz

Signal Generator

(local oscillator)

Filter

IF = 321 MHz

Selected Offset

321 MHz

−679 MHz

Agilent N5181A/82AMXGSignal Generators User’sGuide 49

IF Amplifier

IF Output 321 MHz

SIgnal Generator Display

1321 MHz (Antenna Frequency)

321 MHz (IF Output)

Optimizing Performance Using an Output Offset, Reference, or Multiplier

Setting an Output Reference

Using an output reference, the signal generator can output a frequency or amplitude that is offset (positive or negative) by the entered value from a chosen reference value.

RF Output = reference value + entered value

To set a reference:

1. Set the frequency or amplitude to the value you want as the output reference level.

2. Frequency: Press Frequency > Freq Ref Set

The frequency displays 0.00 Hz, indicating that this is the RF output frequency “zero level.” All frequencies entered are interpreted as being relative to this reference frequency.

Amplitude: Press Amptd > More > Amptd Ref Set

The amplitude displays 0.00 dB, indicating that this is the RF output amplitude “zero level.” All amplitudes entered are interpreted as being relative to this reference amplitude.

Indicates that a reference is on

Examples

Parameter

Reference: 50 MHz 50 MHz 2 GHz A reference value must be positive. Entered (and displayed) Value: 2 MHz −2 MHz −1 GHz The ent ered value can be p ositive or ne gative.

Output Frequency: 52 MHz 48 MHz 1 GHz

Example#1Example#2Example

Comments

The signal generator alerts you if the output frequency or amplitude is out of range.

To set a new frequency or amplitude reference, turn the frequency reference off, and then follow the steps above.

50 Agilent N5181A/82A MXG Signal Generators User’s Guide

Using an Output Offset, Reference, or Multiplier

Optimizing Performance

Setting a Frequency Multiplier

Using a frequency multiplier, the signal generator can display a frequency that is the multiple (positive or negative) of the output value.

Displayed Value = multiplier value × output frequency Output Frequency = displayed value ÷ multiplier value

To set a frequency multiplier:

1. Press Frequency > Freq Multiplier > multiplier value > x.

2. Set the desired frequency. The display equals the output frequency times the multiplier value.

Indicates that a frequency multiplier is on

Examples

Parameter

Frequency Multiplier: 3 −3 4 A multiplier value can be positive or negative. Entered (and displayed) Value: 600 MHz −600 MHz 8 GHz

Output Frequency: 200 MHz 200 MHz 2 GHz

Example#1Example#2Example

Comments

The signal generator alerts you if the output frequency is out of range.

When using the signal generator as the input to a system, you can set the frequency multiplier so that the signal generator displays the output of the system, as illustrated below using a doubler:

Signal Generator Doubler

Input = 2 GHz

Output = 4 GHz

Selected Multiplier

Agilent N5181A/82AMXGSignal Generators User’sGuide 51

Entered/Displayed Frequency

4 GHz

Signal Generato Output

2 GHz

Optimizing Performance Using an Output Offset, Reference, or Multiplier

When measuring mixers, the frequency multiplier and frequency offset are often used together. In the

upconverter example below, the multiplier is set to −1 and the offset is set to 3 GHz so that the

signal generator displays f

Mixer

fRF = 2200 - 2400 MHz

fLO = 800 − 600 MHz

Signal Generator

(local oscillator)

fIF = 3000 MHz

Selected Multiplier

−1

Selected Offset

3000 MHz 3000 MHz

Entered/Displayed Frequency (fRF)

2200 MHz 2400 MHz

Signal Generator Output (fLO)

800 MHz 600 MHz

52 Agilent N5181A/82A MXG Signal Generators User’s Guide

5 Using Analog Modulation (Option UNT Only)

F a

Chapter 3, “Basic Operation,” on page 23 and familiarize yourself with the information in that

chapter.

• The Basic Procedure on page 54

• Using an External Modulation Source on page 55

• Removing a DC Offset on page 55

Figure 5-1 Analog Modulation Softk eys

See

page 55

or details on each key, use key help

s described on see page23.

Agilent N5181A/82A MXG Signal Generators User’s Guide 53

See

page 55

See

page 55

Using Analog Modulation (Option UNT Only) The Basic Procedure

The Basic Procedure

1. Preset the signal generator.

2. Set the carrier (RF) frequency.

3. Set the RF amplitude.

4. Configure the modulation:

AM FM ΦM

a. Press AM

b. Set the AM type (linear or exponential):

AMType to highlight desired type

c. Set the depth:

AMDepth > value > %

d. Set the rate:

AM Rate > value > frequency unit

a. Press FM/ΦM

b. Set the deviation:

FM Dev > value > frequency unit

c. Set the rate:

FM Rate > value > frequency unit

a. Press FM/ΦM > FM ΦM

b. Set the BW (normal or high):

FM ΦM to highlight desired type

c. Set the deviation:

ΦMDev > value > pi rad

d. Set the rate:

ΦM Rate > value > frequency unit

5. Turn on the modulation:

AM FM ΦM

AM Off On softkey to On FM Off On softkey to On ΦM Off On softkey to On

The appropriate modulation annunciator displays, indicating that you enabled modulation.

6. Turn on the RF output.

The RF output LED lights, indicating that the signal is transmitting from the RF output connector.

If the modulation does not seem to be working properly, refer to “No Modulation at the RF Output”

on page 143.

See also “Modulating the Carrier Signal” on page 34.

54 Agilent N5181A/82A MXG Signal Generators User’s Guide

Using an External Modulation Source

Currently selected modulation.

Select to use external modulation

Rear panel inputs are described on page 9

AM input

FM or ΦM input

Default

Using Analog Modulation (Option UNT Only)

Using an External Modulation Source

Removing a DC Offset

To eliminate an offset in an externally applied FM or ΦM signal, perform a DCFM or DCΦM

Calibration.

NOTE You can perform this calibration for internally generated signals, but DC offset is not usually

1. Set up and turn on the desired modulation.

2. Press FM/ΦM > More > DCFM/DCΦM Cal.

Performing the calibration with a DC signal applied removes any deviation caused by the DC signal, and the applied DC level becomes the new zero reference point. When you disconnect the DC signal, perform the calibration again to reset the carrier to the correct zero reference.

Agilent N5181A/82A MXG Signal Generators User’s Guide 55

a characteristic of an internally generated signal.

Using Analog Modulation (Option UNT Only) Using an External Modulation Source

56 Agilent N5181A/82A MXG Signal Generators User’s Guide

6 Using Pulse Modulation (Option UNU)

Chapter 3, “Basic Operation,” on page 23 and familiarize yourself with the information in that

chapter.

• Pulse Characteristics on page 59

• The Basic Procedure on page 61

• Example on page 61

Agilent N5181A/82AMXGSignal Generators User’sGuide 57

Using Pulse Modulation (Option UNU)

F a

D r N I

Figure 6-1 Pulse Softkeys

etermines how the signal generator

esponds to an external pulse signal.

ormal = high state.

nvert = low state.

Pulse Characteristics

Using Pulse Modulation (Option UNU)

Pulse Characteristics

NOTE When using very narrow pulses that are below the signal generator’s ALC pulse width

specification, or leveled pulses with an unusually long duty cycle, it is often useful to turn ALC off (see page 47).

Pulse Source Type

Square

Free Run

(default)

Triggered Internal pulse train  User Defined

Adjustable Doublet

Trigger Doublet

Gated Internal gated pulse train  User Defined

External

All delays, widths, and periods have a resolution of 10 ns.

A signal at the rear panel pulse connector must be held high for at least 20 ns to trigger an internally generated pulse.

Internal free run pulse train with 50% duty cycle.

Internal free run pulse train User Defined User Defined 

Two internal pulse trains for each trigger event.

External pulse signal at the rear panel Pulse connector

Determined by user defined rate.

Peri od



  

Width & Delay

User Defined:

First pulse is relative to the rising edge of trigger signal.

Second pulse is relative to the rising edge of first pulse.

See Figure 6- 2 on page 60

The first pulse follows the trigger sig nal.

Second pulse is user defined.

See Figure 6- 3 on page 60

 

Uses T rigger Event

✓

ear panel inputs are described on page 9

External pulse input

Agilent N5181A/82AMXGSignal Generators User’sGuide 59

Using Pulse Modulation (Option UNU)

T t

Pulse Characteristics

Figure 6-2 Adjustable Doublet

External Trigger

RF Output

Delay

he delay of the first pulse is measured from

he leading edge of the external trigger signal.

Figure 6-3 Trigger Doublet

External Trigger

Width

Delay

The delay of the second pulse is me asured fro m the leading edge of the first pulse.

Width

RF Output

Delay Width

The first pulse follows the external trigger signal.

The delay of the second pulse is me asured fro m the leading edge of the external trigger signal.

60 Agilent N5181A/82A MXG Signal Generators User’s Guide

Using Pulse Modulation (Option UNU)

The Basic Proc edure

The Basic Procedure

1. Preset the signal generator.

2. Set the carrier (RF) frequency.

3. Set the RF amplitude.

4. Configure the modulation:

a. Set the pulse source: Press Pulse > Pulse Source > selection

b. Set the parameters for the selected pulse source:

Square Free Run (default) Triggered Adj ust abl e Doublet Trigger Doublet Gated External

Pulse Rate  

 Pulse Period  Pulse Period   Pulse Delay Pulse Delay Pulse Delay Pulse Delay   Pulse Width Pulse Width Pulse Width Pulse Width Pulse Width   Pulse 2 Delay   Pulse 2 Width 

5. Turn on the modulation: Pulse Off On softkey to On. The the PULSE annunciator lights, indicating that you enabled modulation.

6. Output the modulated signal from the signal generator: Press the front panel RF On Off key.

The RF output LED lights, indicating that the signal is transmitting from the RF output connector.

See also, “Modulating the Carrier Signal” on page 34.

Example

The following example uses the factory preset pulse source and delay.

Output: A 2 GHz, 0 dBm carrier modulated by a 24 µs pulse that has a period of 100 µs.

1. Preset the signal generator.

2. Set the frequency to 2 GHz.

3. Set the amplitude to 0 dBm.

4. Set the pulse period to 100 microseconds: Press Pulse > Pulse Period > 100 > usec.

5. Set the pulse width to 24 microseconds: Press Pulse > Pulse Width > 24 > usec

6. Turn on both the pulse modulation and the RF output. The PULSE annunciator displays and the RF output LED lights.

If the modulation does not seem to be working properly, refer to “No Modulation at the RF Output”

on page 143.

Agilent N5181A/82AMXGSignal Generators User’sGuide 61

Using Pulse Modulation (Option UNU) Example

62 Agilent N5181A/82A MXG Signal Generators User’s Guide

7 Basic Digital Operation—No BBG Option Installed

Before using this information, you should be familiar with the basic operation of the signal generator. If you are not comfortable with functions such as setting power level and frequency, refer to Chapter

3, “Basic Operation,” on page 23 and familiarize yourself with the information in that chapter.

See Also: “Adding Real- Time Noise to a Dual ARB Waveform” on page 130

Agilent N5181A/82AMXGSignal Generators User’sGuide 63

Basic Digital Operation—No BBG Option Installed

F a

I/Q Modulation

The following factors contribute to the error vector magnitude:

• Differences in amplitude, phase, and delay between the I and Q channels

•DC offsets

The I/Q menu provides adjustments to compensate for some of the differences in the I and Q signals or to add impairments.

See also, “Modulating the Carrier Signal” on page 34.

Figure7-1 I/Q Display and Softkeys

This panel displays the current status and settings

This panel displays the external I/Q signal routing.

of the I/Q adjustments. Grey indicates I/Q adjustments are off.

Sets the dc offset

or details on each key, use key help s described on page 23.

Offsets the phase of the Q signal relative to the phase of the I signal. The quadrature adjustment key is calibrated in units of degrees. This adjustment is not calibrated.

The following table shows common uses for the adjustments.

Table 7-1 I/Q Adjustments Uses

I/Q Adjustment Effect Impairment

Offset Carrier Feedthrough dc offset

Quadrature Angle

64 Agilent N5181A/82A MXG Signal Generators User’s Guide

EVM error phase skew

I/Q Images I/Q path delay

Basic Digital Operation—No BBG Option Installed

I/Q Modulation

Configuring the Front Panel Inputs

The Agilent MXG accepts externally supplied analog I and Q signals through the front- panel I Input and Q Input for modulating onto the carrier.

1. Connect I and Q signals to the front panel connectors.

a. Connect an analog I signal to the signal generator’s front- panel I Input.

b. Connect an analog Q signal to the signal generator’s front- panel Q Input.

2. Turn on the I/Q modulator: Press I/Q Off On to On.

3. Configure the RF output:

a. Set the carrier frequency.

b. Set the carrier amplitude.

c. Turn the RF output on.

4. Make adjustments to the I/Q signals (page 64) as needed.

Agilent N5181A/82AMXGSignal Generators User’sGuide 65

Basic Digital Operation—No BBG Option Installed I/Q Modulation

66 Agilent N5181A/82A MXG Signal Generators User’s Guide

8 Basic Digital Operation (Option 651/652/654)

3, “Basic Operation,” on page 23 and familiarize yourself with the information in that chapter.

The features described in this chapter are available only in vector signal generators with Option 651, 652, or 654.

• Wave form F ile Basi c s on page 68

• Storing, Loading, and Playing a Waveform Segment on page 70

• Setting the Baseband Frequency Offset on page 72

• Wave form Seque n c e s on page 74

• Saving a Waveform’s Settings & Parameters on page 78

• Using Waveform Markers on page 82

• Triggering a Waveform on page 98

• Clipping a Waveform on page 105

• Scaling a Waveform on page 114

• I/Q Modulation on page 121

See Also: “Adding Real- Time Noise to a Dual ARB Waveform” on page 130

Agilent N5181A/82AMXGSignal Generators User’sGuide 67

Basic Digital Operation (Option 651/652/654) Waveform File Basics

Waveform File Basics

There are two types of waveform files:

•A segment is a waveform file that you download to the signal generator.

For information on creating and downloading waveform files, refer to the Programming Guide.

•A sequence is a file you create in the signal generator that contains pointers to one or more

waveform files (segments, other sequences, or both).

For information on creating sequences, see page 74.

Signal Generator Memory

The signal generator has two types of memory:

• Volatile memory, baseband generator (BBG) media, where waveform files are played from or

edited.

• Non- volatile memory, either internal (int) or external (USB) media, where waveform files are

stored.

Dual ARB Player

The dual ARB waveform player enables you to play, rename, delete, store, and load waveform files in addition to building waveform sequences. The dual ARB waveform player also provides markers (page 82), triggering (page 98), clipping (page 105), and scaling (page 114) capabilities.

Most procedures in this section start from the Dual ARB menu, shown below.

68 Agilent N5181A/82A MXG Signal Generators User’s Guide

Figure 8-1 Dual ARB Softkeys

If you set the ARB sample clock when the dual A RB

F a

Note: This is second of

or details on each key, use key help s described on page23.

three Arb menus.

Note: This is the

first of three Arb menus.

page 70

page 98

page 82

Basic Digital Operation (Option 651/652/654)

is off, the new settin g is appl ied when th e d ual AR player is turned on; this setting survives toggling the Dual ARB player off and on.

page 130

page 114

page 72

Waveform File Basics

page 74

page 78

Note: This is third of

three Arb menus

page 10

page 11

page 10

Agilent N5181A/82AMXGSignal Generators User’sGuide 69

Basic Digital Operation (Option 651/652/654)

F a

Storing, Loading, and Playing a Waveform Segment

See also, Viewing, Saving, and Recalling Data on page 35.

Figure 8-2 Waveform Segment Softkeys

Note: When a sequence is highlighted, this key name changes to Show Waveform Sequence Contents.

or details on each key, use key help s described on page23.

See page82

Use the arrow keys or kn ob to highlight a letter or character

Storing/Renaming a Waveform Segment to Non-Volatile Memory (Internal or External Media)

Use the following steps to store a copy of a file in BBG memory to the currently selected media (page 41). If you have not downloaded a waveform segment, either refer to the Programming Guide, or use one of the factory- supplied segments.

1. Press Mode > Dual ARB > Select Waveform > Waveform Segments.

2. In the Segment On BBG Media column, highlight any waveform segment.

3. Press Load Store to highlight Store.

4. Highlight the waveform segment you want to store.

5. Optionally rename the segment.

If there is already a copy of this segment in the currently selected media and you do not want to overwrite it, rename the waveform segment before you store it:

a. Press More > Rename Segment > Clear Text.

b. Enter a name for the waveform segment.

c. Press Enter > More.

d. Highlight the waveform segment that was renamed.

6. Press Sto re Se g ment to currently selected Media.

70 Agilent N5181A/82A MXG Signal Generators User’s Guide

Basic Digital Operation (Option 651/652/654)

Storing, Loading, and Playing a Waveform Segment

7. R epe at Step 4 through Step 6 for all segments that you want to store.

To save all segments from BBG media to the currently selected media, press

Store All to currently selected Media.

Loading a Waveform Segment into BBG Media (Volatile Memory)

Waveform segments must reside in BBG media before they can be played, edited, or included in a sequence. Cycling power or rebooting the signal generator deletes the files in BBG media.

NOTE Each time the instrument powers up, two factory- supplied segments are automatically

created in BBG media: RAMP_TEST_WFM and SINE_TEST_WFM.

1. Press Mode > Dual ARB > Select Waveform > Waveform Segments.

2. Press Load Store to highlight Load.

3. Highlight the waveform segment you want to load.

4. If there is already a copy of this segment in the currently selected media and you do not want to overwrite it, rename the waveform segment before you load it (refer to the previous procedure).

5. Press Load Segment From currently selected Media.

To load all files from the currently selected media into BBG media, press

Load All From currently selected Media.

Playing a Waveform Segment

1. Press Mode > Dual ARB > Select Waveform.

2. In the Segment on BBG Media column, highlight the waveform segment you want to play.

3. Press Select Waveform > ARB Off On to On. This plays the selected waveform segment. During the waveform segment generation, both the I/Q

and ARB annunciators turn on, and the waveform modulates the RF carrier.

Annunciators display with active waveform (ARB On)

Current waveform selection

4. Configure the RF Output:

a. Set the RF carrier frequency. b. Set the RF output amplitude. c. Turn on the RF output.

The waveform segment is now available at the signal generator’s RF OUTPUT connector.

Agilent N5181A/82AMXGSignal Generators User’sGuide 71

Basic Digital Operation (Option 651/652/654)

Setting the Baseband Frequency Offset

Figure8-3 Baseband Frequency Offset Softke y

The settings in this menu can be stored to the file header, see page 78.

See page 130

See page114

Frequency offset setting.

For details on each key, use key hel as described on page 23.

The baseband frequency offset enables you to shift the baseband frequency up to ±50 MHz within the BBG 100 MHz signal bandwidth, depending on the signal generator’s baseband generator option. Common uses for the offset feature include:

• offsetting the carrier from any LO feedthrough (carrier signal spur at the carrier frequency)

• sum the baseband signal with external I and Q inputs to create a multicarrier signal

• use the signal generator’s I/Q signal as an IF

NOTE Changing the baseband frequency offset may cause a DAC over range condition that

generates error 628, Baseband Generator DAC over range. When this occurs, reduce the waveform runtime scaling value (page 114).

The baseband frequency offset value is one of the file header parameters (page 78), which means you can store this value with the waveform. When you select a waveform with a stored frequency offset value, the signal generator changes the current value to match the stored file header value. If there is no stored baseband offset frequency value for the current waveform, the signal generator uses the last set frequency offset value.

You can also use the Save function (page 35) to store this value as part of the signal generator setup. When you Recall a setup stored with the Save function, the baseband frequency offset value becomes the current instrument setting value, disregarding the stored file header value.

72 Agilent N5181A/82A MXG Signal Generators User’s Guide

Basic Digital Operation (Option 651/652/654)

Setting the Baseband Frequency Offset

Use the following steps to offset the carrier from LO/carrier feedthrough. This example uses the factory supplied waveform, SINE_TEST_WFM. To view the output for this example, connect the RF OUTPUT of the signal generator to the input of a spectrum analyzer.

1. Select and play the waveform.

a. Press Mode > Dual ARB > Selec t Waveform. b. In the Segment On BBG Media column, select SINE_TEST_WFM. c. Press Select Waveform.

2. Generate the waveform: Press ARB Off On to On.

3. Configure the carrier signal:

a. Set the carrier signal to 1 GHz. b. Set the amplitude to 0 dBm. c. Turn on the RF OUTPUT.

4. Press ARB Setup > Baseband Freque ncy Offset > 20 MHz.

The modulated RF signal is now offset from the carrier frequency by 20 MHz as shown in the following figures.

Modulated carrier with 0 Hz baseband freque nc y off set

Modulated carrier with 20 MHz baseband frequency offset

LO/carrier feedthrough

Spectrum analyzer set to a span of 100 MHz

Modulated RF signal

Agilent N5181A/82AMXGSignal Generators User’sGuide 73

Basic Digital Operation (Option 651/652/654) Waveform Sequences

Wavef orm S equences

Figure 8-4 Waveform Sequence Softkeys

Mode > Dual ARB >

To display this softkey, highlight a waveform sequence

Sequence name

Sequence contents

see page 95

For details on each key, use key help as described on page23.

A waveform sequence is a file that contains pointers to one or more waveform segments or other waveform sequences, or both. This lets the signal generator play multiple waveform segments, or other sequences, or both thereby eliminating the need to stop waveform playback just to select another waveform.

The segments that a waveform sequence points to are not automatically stored when you store the sequence; you must also store the individual segments or they are lost when you turn off or reboot the signal generator. If the segments are located in internal/external media, you must load them into BBG media prior to selecting a waveform sequence. If you attempt to play a sequence without the segments loaded into BBG media, the signal generator reports: ERROR: 629, File format invalid. If this happens and the segments are not stored in internal/external media, you must recreate the segments using the same file names that the sequence points to before you can play the sequence.

74 Agilent N5181A/82A MXG Signal Generators User’s Guide

Basic Digital Operation (Option 651/652/654)

Waveform Sequ ences

Creating a Sequence

A waveform sequence can contain up to 1,024 segments and have both segments and other sequences (nested sequences). The signal generator lets you set the number of times the segments and nested sequences repeat during play back. But there is a difference between repeating a segment versus repeating a nested sequence. Each segment can repeat up to 65,535 times, but no matter how many times a segment repeats, it counts as a single segment. However each repetition of a nested sequence counts as additional segments.

Segment 1

Sequence A

Waveform Sequence

Sequence B

Segment 2

Sequence A repeated 4x

Segment 3

8 Segments

The maximum number of times that a nested sequence can repeat is based on the number of segments in the nested sequence and the remaining number of allowed segments (1,024). For example, with a sequence that contains 24 segments and one nested sequence with 4 segments, the nested sequence is limited to 250 repetitions:

24 + (4 × 250) = 1,024 maximum number of segments per sequence

Even though there is a limiting factor on the maximum number of times that a nested sequence can repeat, each segment within the nested sequence can repeat up to 65,535 times.

2 segments

11 seg ments

9 segments

Example

Use the following procedure to create and store a waveform sequence using one repetition each of two different segments.

Assumption: The waveform segments are in BBG media (volatile memory). For information on loading waveform segments into BBG media, see page 71.

1. Select the first segment:

a. Press Mode > Dual ARB > More > More > Waveform Sequences > Build New Waveform Sequence >

Insert Waveform.

b. Highlight the desired waveform segment and press Insert.

2. Select the second segment:

a. Highlight the next desired waveform segment and press Insert. b. Press Done Inserting

3. Name and store the waveform sequence to the Seq file catalog: a. Press More > Name and Store. b. Enter a file name and press Enter.

See also, “Viewing the Contents of a Sequence” on page 76 and “Setting Marker Points in a Waveform

Segment” on page 89.

Agilent N5181A/82AMXGSignal Generators User’sGuide 75

Basic Digital Operation (Option 651/652/654) Waveform Sequences

Viewing the Contents of a Sequence

There are two ways to view the contents of a waveform sequence, through the Waveform Sequences softkey or the Select Waveform softkey:

Waveform Sequences Softkey

1. Press Mode > Dual ARB > More > More > Waveform Sequences.

2. Highlight the desired sequence.

3. Press Show Waveform Sequence Contents.

Waveform Select Softkey

1. Press Mode > Dual ARB > Select Waveform.

2. In the Sequence On column, highlight the desired waveform sequence.

3. Press Show Waveform Sequence Contents.

Editing a Sequence

When editing a waveform sequence, you can:

• change the number of times each segment or nested sequence plays

• delete segments or nested sequences from the sequence

• add segments or nested sequences to the sequence

• toggle markers on and off (described on page 95)

• save changes either to the current waveform sequence or as a new sequence If you exit the sequence editing menu before saving changes, the changes are lost. Sequences save to the Seq file catalog.

CAUTION If you edit and resave a segment used in a sequence, the sequence does not

Use the following steps to edit a sequence that has two different segments so that the first segment repeats 100 times and the second segment repeats 200 times, then save the changes.

Assumption: A waveform sequence that has two different segments has been created and stored (see previous example on page 75).

1. Select the sequence:

Press Mode > Dual ARB > More > More > Waveform Sequences > highlight the desired sequence > Edit Selected Waveform Sequence.

2. Change the first segment so that it repeats 100 times:

Highlight the first segment entry and press Edit Repetitions > 100 > Enter.

The cursor moves to the next entry.

3. Change the repetition for the selected entry to 200:

Press Edit Repetitions > 200 > Enter.

4. Save the changes made in the previous steps:

Press More > Name and Store > Enter.

To save the changes as a new sequence:

76 Agilent N5181A/82A MXG Signal Generators User’s Guide

automatically update the RMS value in its header. You must select and update the sequence header information (page 78).

Basic Digital Operation (Option 651/652/654)

Waveform Sequ ences

a. Press More > Name and Store > Clear Text.

b. Enter a file name (for example, SINE100+RMP200).

c. Press Enter.

The edited sequence saves as a new waveform sequence.

Playing a Sequence

If you have not created a waveform sequence, refer to “Creating a Sequence” on page 75.

NOTE To play a waveform segment individually or as part of a waveform sequence, the segment

must reside in BBG media. See also, “Loading a Waveform Segment into BBG Media (Volatile

Memory)” on page 71.

1. Select a waveform sequence:

a. Press Mode > Dual ARB > Selec t Waveform. b. Highlight a waveform sequence (for this example, SINE100+RMP200) from the Sequence On

column.

c. Press Select Waveform. The display shows the currently selected waveform (for example, Selected Waveform:

SEQ:SINE100+RMP200).

Annunciators display with active waveform (ARB On)

Current waveform selection

2. Generate the waveform:

Press ARB Off On to On.

This plays the selected waveform sequence. During the waveform sequence generation, both the I/Q and ARB annunciators turn on, and the waveform modulates the RF carrier.

3. Configure the RF output:

a. Set the RF carrier frequency. b. Set the RF output amplitude. c. Turn on the RF output.

The waveform sequence is now available at the signal generator’s RF OUTPUT connector.

Agilent N5181A/82AMXGSignal Generators User’sGuide 77

Basic Digital Operation (Option 651/652/654)

M M H

Saving a Waveform’s Settings & Parameters

This section describes how to edit and save a file header. When you download only a waveform file (I/Q data, which the signal generator treats as a waveform segment), the signal generator automatically generates a file header and a marker file with the same name as the waveform file. Initially the file header has no signal generator settings saved to it, and the marker file consists of all zeros. For a given waveform, you can save signal generator settings and parameters in its file header and marker settings in its marker file (page 82); when you load a stored waveform file into BBG media, the file header and marker file settings automatically apply to the signal generator so that the dual ARB player sets up the same way each time the waveform file plays.

Figure 8-5 Header Utilities Softkeys

ode > Dual ARB > ore > More >

eader Utilities >

See page 79

For details on each key, use key help as described on page23.

When you create a waveform sequence (as described on page 75), the signal generator automatically creates a waveform sequence header that takes priority over the individual waveform segment headers. During a waveform sequence playback, the segment headers are ignored, except to verify that all required options are installed. Storing a waveform sequence also stores its file header.

Some of the current signal generator settings shown in the file header, appear as part of the softkey labels and others appear in the dual ARB summary display, shown in the following example.

All settings in this menu can be stored to the file header.

Softkey label, file header

ARB summary, file header settings

78 Agilent N5181A/82A MXG Signal Generators User’s Guide

setting

Softkey labels, file header settings

Basic Digital Operation (Option 651/652/654)

Saving a Waveform’s Settings & Parameters

Viewing and Modifyi ng Header Information

The following example uses the factory- supplied waveform file RAMP_TEST_WFM.

1. From BBG media, select the waveform RAMP_TEST_WFM:

a. Press Mode > Dual ARB > Selec t Waveform. b. In the Segment On column, highlight the waveform RAMP_TEST_WFM. c. Press Select Waveform.

2. Open the Header Utilities menu:

Press More > More > Header Utilities The Figure 8- 6 shows the default file header for the factory- supplied waveform RAMP_TEST_WFM.

The Header Field column lists the file header parameters; use the Page Down key to see them all. The Saved Header Settings column shows that most of the settings are Unspecified.

Unspecified means that there is no setting saved for that particular parameter. The Current Inst. Settings column shows the current signal generator settings. In this

example, these are the settings that you will save to the file header.

NOTE If a setting is unspecified in the file header, the signal generator uses its current value for

that setting when you select and play the waveform.

Figure 8-6 Example File Header

Mode > Dual ARB > More > More > Header Utilities >

Default header settings

Current signal generator settings

The name of the waveform file.

The description can be up to 32-characters.

Resets the saved header settings entries to default settings

3. Save the information in the Current Inst. Settings column to the file header:

Press Save Setup To Header. Both the Saved Header Settings column and the Current Inst. Settings column now display

the same values; the Saved Header Settings column lists the settings saved in the file header.

Agilent N5181A/82AMXGSignal Generators User’sGuide 79

Basic Digital Operation (Option 651/652/654) Saving a Waveform’s Settings & Parameters

4. Edit and Update Settings

a. Return to the ARB Setup menu:

Press Return > More > ARB Setup.

From this menu you can access some of the signal generator settings that are saved to the file header. Figure 8- 1 on page 69 shows the ARB Setup softkeys used in the following steps.

b. Set the ARB sample clock to 5 MHz:

Press ARB Sample Clock > 5 > MHz.

c. Set waveform runtime scaling to 60%:

Press Waveform Runtime Scaling > 60 > %.

d. Return to the Header Utilities menu:

Press Return > More > More > Header Utilities. As shown in the following figure, the Current Inst. Settings column now reflects the

changes to the current signal generator setup, but the saved header values have not changed.

Values differ between the two columns

e. Save the current settings to the file header:

Press the Save Setup To Header softkey. The settings from the Current Inst. Settings column now appear in the Saved Header

Settings column. This saves the new current instrument settings to the file header.

If you change any of the signal generator settings listed in the file header after you select the waveform file, the changed setting(s) appear in the file header’s Current Inst. Settings column and are used instead of the saved header settings. To reapply the saved header settings, reselect the waveform for playback.

80 Agilent N5181A/82A MXG Signal Generators User’s Guide

Basic Digital Operation (Option 651/652/654)

F a

Saving a Waveform’s Settings & Parameters

Viewing & Editing a Header without Selecting the Waveform

As described on page 79, you can view and edit a waveform’s header information after you select the waveform; you can also edit waveform header information without selecting a waveform, or for another waveform than the one that is currently selected.

1. Access the file header utilities menu:

Press Mode > Dual ARB > More > More > Header Utilities > More > Select Different Header.

The signal generator displays an alphabetical list of the waveform files in the media that was last selected. The following figure shows an example of the factory- supplied waveforms in BBG media.

Type: WFM1 = Volatile Segment NVWFM = Non-Volatile Segment

Active catalog

SEQ = Sequence

Active waveform catalog

Active media

or details on each key, use key help

s described on page 23.

Waveforms segments stored in BBG media

Waveform segments stored in internal or external media

Waveform sequences stored in internal or external media

2. If the desired catalog is not displayed, select it.

3. Highlight the desired waveform file and press Select Header.

The signal generator displays the file header for the selected waveform file.

4. To edit the header, press More, and proceed as described in Step 4 on page 80 (Viewing and

Modifying Header Information section).

Agilent N5181A/82AMXGSignal Generators User’sGuide 81

Basic Digital Operation (Option 651/652/654) Using Waveform Markers

Using Waveform Markers

The signal generator provides four waveform markers to mark specific points on a waveform segment. When the signal generator encounters an enabled marker, an auxiliary signal is routed to a rear panel event output that corresponds to the marker number.

• Event 1 is available at both the EVENT 1 BNC connector (see page 12), and a pin on the AUXILIARY I/O connector (see page 13).

• Events 2 through 4 are available at pins on the AUXILIARY I/O connector (see page 13).

You can use an auxiliary output signal to synchronize another instrument with the waveform, or as a trigger signal to start a measurement at a given point on a waveform.

You can also configure markers to initiate ALC hold or RF Blanking (which includes ALC hold). Refer to “Using Waveform Markers” on page 82 for det ails.

When you download a waveform file that does not have a marker file associated with it, the signal generator creates a marker file without any marker points. Factory- supplied segments have a marker point on the first sample for all four markers.

The following procedures demonstrate how to use markers while working in the dual ARB player. These procedures also discuss two types of points: a marker point and a sample point. A marker point is a point at which a given marker is set on a waveform; you can set one or more marker points for each marker. A sample point is one of the many points that compose a waveform.

There are three basic steps to using waveform markers:

“Clearing Marker Points from a Waveform Segment” on page 88

“Setting Marker Points in a Waveform Segment” on page 89

“Controlling Markers in a Waveform Sequence” on page 95

This section also provides the following information:

• “Waveform Marker Concepts” on page 83

• “Accessing Marker Utilities” on page 87

• “Viewing Waveform Segment Markers” on page 88

• “Viewing a Marker Pulse” on page 92

• “Using the RF Blanking Marker Function” on page 93

• “Setting Marker Polarity” on page 94

82 Agilent N5181A/82A MXG Signal Generators User’s Guide

Basic Digital Operation (Option 651/652/654)

W a

E A

Using Waveform Markers

Waveform Marker Concepts

The signal generator’s Dual ARB provides four waveform markers to mark specific points on a waveform segment. You can set each marker’s polarity and marker points (on a single sample point or over a range of sample points). Each marker can also perform ALC hold, or RF Blanking and ALC hold.

Positive

Marker

File

Bit N

Set Marker

On Off

hen the signal generator encounters an enabled marker (described on page 95), an

uxiliary output signal is generated and routed to the rear panel.

vent 1 is available at the EVENT 1 BNC connector (see page 12), and at a pin on the UXILIARY I/O connector (see page 13).

vents 2 through 4 are available at pins on the AUXILIARY I/O connector (see page 13).

Marker

Polarity

Negative

Marker N

RF Blank Off On

Marker N

ALC Hold Off On

EVENT N

Marker N

Blanks RF

when Marker i

Low

RF Blank Only: includes ALC Hold

Marker N

Holds ALC

when Marker i

Low

Marker Signal Response

The signal generator aligns the marker signals with the I and Q signals at the baseband generator. However some settings such as amplitude, filters, and so forth within the RF output path can create delays between the marker EVENT output signal and the modulated RF output. When using the marker EVENT output signal, observe the signals (marker relative to modulated RF) for any latency, and if needed, reset the marker point positions, include delay (page 125), or both.

Marker File Generation

Downloading a waveform file (as described in the Programming Guide) that does not have a marker file associated with it causes the signal generator to automatically create a marker file, but does not place any marker points.

Marker Point Edit Requirements

Before you can modify a waveform segment’s marker points, the segment must reside in BBG media (see “Loading a Waveform Segment into BBG Media (Volatile Memory)” on page 71).

Saving Marker Polarity and Routing Settings

Marker polarity and routing settings remain until you reconfigure them, preset the signal generator, or cycle power. To ensure that a waveform uses the correct settings when it is played, set the marker polarities or routing (RF Blanking and ALC Hold) and save the information to the file header (page 78).

NOTE When you use a waveform that does not have marker routings and polarity settings stored in

Agilent N5181A/82AMXGSignal Generators User’sGuide 83

the file header, and the previously played waveform used RF Blanking, ensure that you set

RF Blanking to None. Failure to do so can result in a no RF output condition or a distorted

Basic Digital Operation (Option 651/652/654) Using Waveform Markers

waveform.

ALC Hold Marker Function

While you can set a marker function (described as Marker Routing on the softkey label) either before

or after you set marker points (page 89), setting a marker function before setting marker points may cause power spikes or loss of power at the RF output.

Use the ALC hold function by itself when you have a waveform signal that incorporates idle periods, burst ramps, or when the increased dynamic range encountered with RF blanking (page 93) is not desired.

The ALC hold marker function holds the ALC circuitry at the average value of the sampled points set by the marker(s). For both positive and negative marker polarity, the ALC samples the RF output signal (the carrier plus any modulating signal) when the marker signal goes high:

Positive: The signal is sampled during the on marker points.

Negative The signal is sampled during the off marker points.

NOTE Because it can affect the waveform’s output amplitude, do not use the ALC hold for longer

than 100 ms. For longer time intervals, refer to “Power Search Mode” on page 48.

Positive Polarity

CAUTION Incorrect ALC sampling can create a sudden unleveled condition that may create a spike

in the RF output, potentially damaging a DUT or connected instrument. To prevent this condition, ensure that you set markers to let the ALC sample over an amplitude that accounts for the higher power levels encountered within the signal.

84 Agilent N5181A/82A MXG Signal Generators User’s Guide

Example of Correct Use

Waveform: 1022 points Marker range: 95-97 Marker polarity: Positive

Basic Digital Operation (Option 651/652/654)

Using Waveform Markers

This example shows a marker set to sample the waveform’s area of highest amplitude. Note that the marker is set well before the waveform’s area of lowest amplitude. This takes into account any response difference between the marker and the waveform signal.

The ALC samples the waveform when the marker signal goes high, and uses the average of the sampled waveform to set the ALC circuitry.

Here the ALC samples during the on marker points (positive polarity).

Marker

Close-up of averaging

Marker

Example of Incorrect Use

Waveform: 1022 points Marker range: 110-10 22 Marker polarity: Positive

Marker

This example shows a marker set to sample the low part of the same waveform, which sets the ALC modulator circuitry for

Marker

MarkerMarker

that level; this usually results in an unleveled condition for the signal generator when it encounters the high amplitude of the pulse.

Agilent N5181A/82AMXGSignal Generators User’sGuide 85

Pulse Unleveled

Basic Digital Operation (Option 651/652/654)

Example of Incorrect Use

S i a

Using Waveform Markers

Waveform: 1022 points Marker range: 110-1022 Marker polarity: Negative

This figure shows that a negative polarity marker goes low during the marker on points; the marker signal goes high during the off points. The ALC samples the waveform during the off marker points.

ampling both on and off time sets the modulator circuitry

ncorrectly for higher signal levels. Note the in creased amplitude

t the beginning of the pulse.

Marker On

Sample range begins on first point of signa

Marker

Off

Marker On

Negative range set between signal and off time

Marker

Off

Marker

86 Agilent N5181A/82A MXG Signal Generators User’s Guide

Accessing Marker Utilities

M o s

Note: This is the second Arb menu.

Mode > Dual ARB > More >

Basic Digital Operation (Option 651/652/654)

Using Waveform Markers

For details on each key, use key help as described on page23.

The settings in these me nus can be stored to the file header, see page 78.

The display below shows the I and Q components of the wave form , and the marker points set in a factory-supplied segment.

First sample poin shown on displa

These softkeys change the range of waveform sample points shown on the marker display.

Each press of the softkey changes the sample range by

arker points n first ample point

Agilent N5181A/82AMXGSignal Generators User’sGuide 87

approximately a factor of two.

Basic Digital Operation (Option 651/652/654) Using Waveform Markers

Viewin g Waveform Segment Markers

Markers are applied to waveform segments. Use the following steps to view the markers set for a segment (this example uses the factory- supplied segment, SINE_TEST_WFM).

1. In the second Arb menu (page 87), press Set Markers.

2. Highlight the desired waveform segment (in this example, SINE_TEST_WFM).

3. Press Display Waveform and Markers > Zoom in Max.

The maximum zoom in range is 28 points.

Experiment with the Zoom functions to see how they display the markers.

The display can show a maximum of 460 points; displayed waveforms with a sample point range greater than 460 points may not show the marker locations.

Clearing Marker Points from a Waveform Segment

When you set marker points they do not replace points that already exist, but are set in addition to existing points. Because markers are cumulative, before you set points, view the segment (page 88) and remove any unwanted points. With all markers cleared, the level of the event output signal is 0V. To clear marker points on a segment, the segment must reside in BBG media (page 71).

Clearing All Marker Points

1. In the second Arb menu (page 87), press Set Markers.

2. Highlight the desired waveform segment (in this example, SINE_TEST_WFM).

3. Highlight the desired marker number: Press Marker 1 2 3 4.

4. For the selected marker number, remove all marker points in the selected segment:

a. Press Set Marker Off Range of Points.

Notice that the softkeys for the first and last marker points correspond with the length of the waveform. The factory- supplied waveform (SINE_TEST_WFM) contains 200 samples. To clear all set marker points, the range must equal to the length of the waveform.

b. Press Apply To Waveform > Return.

5. Repeat from Step 3 for any remaining marker points that you want to remove from the other markers.

Clearing a Range of Marker Points

The following example uses a waveform with marker points (Marker 1) set across points 10−20. This

makes it easy to see the affected marker points. The same process applies whether the existing points are set over a range or as a single point (page 89).‘

1. In the second Arb menu (page 87), press Set Markers, then select Marker 1.

2. Set the first sample point that you want off (for this example, 13):

Press SetMarker Off Range Of Points > First Mkr Point > 13 > Enter.

3. Set the last marker point in the range that you want off to a value less than or equal to the number of points in the waveform, and greater than or equal to the value set in Step 2 (for this example, 17):

88 Agilent N5181A/82A MXG Signal Generators User’s Guide

Basic Digital Operation (Option 651/652/654)

Using Waveform Markers

Press Last Mkr Point > 17 > Enter > Apply To Waveform > Return.

This turns off all marker points for the active marker within the range set in Steps 2 and 3, as shown at right.

How to view markers is described on page 88.

Clearing a Single Marker Point

Use the steps described in “Clearing a Range of Marker Points” on page 88, but set both the first and last marker point to the value of the point you want to clear. For example, if you want to clear a marker on point 5, set both the first and last value to 5.

Setting Marker Points in a Waveform Segment

To set marker points on a segment, the segment must reside in BBG media (page 71).

When you set marker points, they do not replace points that already exist, but are set in addition to existing points. Because markers are cumulative, before you set marker points within a segment, view the segment (page 88) and remove any unwanted points (page 88).

Placing a Marker Across a Range of Points

1. In the second Arb menu (page 87), press Set Markers.

2. Highlight the desired waveform segment.

3. Select the desired marker number: Press Marker 1 2 3 4

4. Set the first sample point in the range (in this example, 10):

Press SetMarker On Range Of Points > First Mkr Point > 10 > Enter.

5. Set the last marker point in the range to a value less than or equal to the number of points in

the waveform, and greater than or equal to the first marker point (in this example, 20):

Press Last Mkr Point > 20 > Enter.

6. Press Apply To Waveform > Return.

This sets a range of waveform marker points. The marker signal starts on sample point 10, and ends on sample point 20, as shown in the following figure.

Agilent N5181A/82AMXGSignal Generators User’sGuide 89

Basic Digital Operation (Option 651/652/654) Using Waveform Markers

How to view markers is described on page 88

90 Agilent N5181A/82A MXG Signal Generators User’s Guide

Agilent N5181A Users Guide

Specifications and Main Features

Frequently Asked Questions

User Manual

Documentation Overview

1 Signal Generator Overview

Signal Generator Features

Front Panel Overview

1. Host USB

2. Display

3. Softkeys

4. Numeric Keypad

5. Arrows and Select

6. Page Up

7. MENUS

8. Trigger

9. Local Cancel/(Es c)

10. Help

11. Preset and User Preset

12. RF Output

13. RF On/Off and LE D

14. Mod On/Off and LED

15. Page Down

16. I Input (vector models only)

17. Q Input (vector models only)

18. Knob

19. Incr Set

20. Return

21. More and LED

22. Power Switch and LEDs

Front Panel Display

1. Active Function Area

2. Frequency Area

3. Annunciators

4. Amplitude Area

5. Error Message Area

6. Text Area

7. Softkey Label Area

Rear Panel Overview

1. AC Power Receptacle

2. SWEEP OUT

3. AM

4. FM

5. PULSE

6. TRIG IN

7. TRIG OUT

8. REF IN

9. 10 MHz OUT

10. GPIB

Digital Modulation Connectors (vector models only)

EXT CLOCK

EVENT 1

PAT TRIG IN

DIGITAL BUS I/O

AUX I/O

2 Setting Preferences & Enabling Options

User Prefere nc es

Display Settings

Power On and Preset

Front Panel Knob Resolution

Upgrading Firmware

Setting Time and Date

Remote Operat i on Preferences

Configuring the GPIB Interface

Configuring the LAN Interface

Enabling LAN Services : Browser, Sockets, and VXI-11

Enabling an Option

Viewing Options and Licenses

3 Basic Operation

Presetting the Signal Generator

Viewing Key Descriptions

Entering and Editing Numbers and Text

Entering Numbers and Moving the Cursor

Entering Alpha Characters

Example: Using a Table Editor

Setting Frequency and Power (Amplitude)

Configuring a Swept Output

Step Sweep

List Sweep

Example: Using a Single Sweep