Agilent 33120A User's Guide

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User’s Guide

Part Number 33120-90005 August 1997

For Safety information, Warranties, and Regulatory information, see the pages behind the Index.

HP 33120A Function Generator /

Arbitrary Waveform Generator

Note: Unless otherwise indicated, this manual applies to all Serial Numbers.

The HP 33120A is a high-performance 15 MHz synthesized function generator with built-in arbitrary waveform capability. Its combination of bench-top and system features makes this function generator a versatile solution for your testing requirements now and in the future.

Convenient bench-top features

• 10 standard waveforms

• Built-in 12-bit 40 MSa/s arbitrary waveform capability

• Easy-to-use knob input

• Highly visible vacuum-fluorescent display

• Instrument state storage

• Portable, ruggedized case with non-skid feet

Flexible system features

• Four downloadable 16,000-point arbitrary waveform memories

• HP-IB (IEEE-488) interface and RS-232 interface are standard

• SCPI (Standard Commands for Programmable Instruments) compatibility

• Optional HP 34811A BenchLink/Arb Waveform Generation Software

for Microsoft

Windows

HP 33120A Function Generator /

Arbitrary Waveform Generator

The Front Panel at a Glance

1 Function / Modulation keys 2 Menu operation keys 3 Waveform modify keys 4 Single / Internal Trigger key

Burst and Sweep only)

(

5 Recall / Store instrument state key 6 Enter Number key 7 Shift / Local key 8 Enter Number “units” keys

Front-Panel Number Entry

You can enter numbers from the front-panel using one of three methods.

Use the knob and the arrow keys to modify the displayed number.

Use the arrow keys to edit individual digits.

Increments the flashing digit.

Decrements the flashing digit.

Moves the flashing digit

to the right.

to the left.

Use the “Enter Number” mode to enter a number with the appropri ate units.

Use “Enter” for those operations that do not require units to be specified (AM Level, Offset, % Duty, and Store/Recall State).

The Front-Panel Menu at a Glance

The menu is organized in a top-down tree structure with three levels.

A: MODulation MENU

1: AM SHAPE  2: AM SOURCE  3: FM SHAPE  4: BURST CNT  5: BURST RATE 



6: BURST PHAS  7: BURST SRC  8: FSK FREQ  9: FSK RATE  10: FSK SRC

B: SWP (Sweep) MENU

1: START F  2: STOP F  3: SWP TIME  4: SWP MODE

C: EDIT MENU

1: NEW ARB  [ 2: POINTS ]  [ 3: LINE EDIT ]  [ 4: POINT EDIT ]  [ 5: INVERT ]  [ 6: SAVE AS ]  7: DELETE

The commands enclosed in square brackets ( [ ] ) are “hidden” until you make a selection from the

NEW ARB command to initiate a new edit session.

D: SYStem MENU

1: OUT TERM  2: POWER ON  3: ERROR  4: TEST  5: COMMA  6: REVISION

E: Input / Output MENU

1: HPIB ADDR  2: INTERFACE  3: BAUD RATE  4: PARITY  5: LANGUAGE

F: CALibration MENU

1: SECURED  [ 1: UNSECURED ]  [ 2: CALIBRATE ]  3: CAL COUNT  4: MESSAGE

The commands enclosed in square brackets ( [ ] ) are “hidden” unless the function generator

is UNSECURED for calibration.

Display Annunciators

Adrs Rmt Trig AM FM Ext FSK Burst Swp

ERROR

Offset Shift Num Arb

Function generator is addressed to listen or talk over a remote interface. Function generator is in remote mode (remote interface). Function generator is waiting for a single trigger or external trigger (Burst, Sweep). AM modulation is enabled. FM modulation is enabled. Function generator is set for an external modulation source (AM, FSK, Burst). FSK (frequency-shift keying) modulation is enabled. Burst modulation is enabled. Sweep mode is enabled. Hardware or remote interface command errors are detected. The waveform is being output with an offset voltage.

“Shift” key has been pressed. “Enter Number” mode is enabled.

Arbitrary waveform function is enabled. Sine waveform function is enabled. Square waveform function is enabled. Triangle waveform function is enabled. Ramp waveform function is enabled.

Press “Shift” again to turn off.

Press “Shift-Cancel” to disable.

To review the display annunciators, hold down the Shift key as you turn on the function generator.

The Rear Panel at a Glance

1 Chassis ground 2 Power-line fuse-holder assembly 3 Power-line voltage setting 4 AM modulation input terminal

Use the front-panel Input / Output Menu to:

5 External Trigger / FSK / Burst modulation

input terminal

6 HP-IB (IEEE-488) interface connector 7 RS-232 interface connector

• Select the HP-IB or RS-232 interface (see chapter 4).

• Set the HP-IB bus address (see chapter 4).

Set the RS-232 baud rate and parity (see chapter 4).

•

In This Book

Quick Start Chapter 1 prepares the function generator for use and helps you get familiar with a few of its front-panel features.

Front-Panel Menu Operation Chapter 2 introduces you to the

front-panel menu and describes some of the function generator’s menu features.

Features and Functions Chapter 3 gives a detailed description of the function generator’s capabilities and operation. You will find this chapter useful whether you are operating the function generator from the front panel or over the remote interface.

Remote Interface Reference Chapter 4 contains reference information to help you program the function generator over the remote interface.

Error Messages Chapter 5 lists the error messages that may appear as you are working with the function generator. Each listing contains enough information to help you diagnose and solve the problem.

Application Programs Chapter 6 contains several remote interface application programs to help you develop programs for your application.

Tutorial Chapter 7 discusses the fundamentals of signal generation and modulation techniques.

Specifications Chapter 8 lists the function generator’s specifications.

For information on using the Phase-Lock Option for the HP 33120A,

refer to the User’s and Service Guide included with the Option 001.

If you have questions relating to the operation of the HP 33120A, call 1-800-452-4844 in the United States, or contact your nearest Hewlett-Packard Sales Office.

If your HP 33120A fails within three years of purchase, HP will repair or replace it free of charge. Call 1-800-258-5165 (“Express Exchange”) in the United States, or contact your nearest Hewlett-Packard Sales Office.

Chapter 1 Quick Start

To prepare the function generator for use 15 If the function generator does not turn on 16 To adjust the carrying handle 18 To set the output frequency 19 To set the output amplitude 20 To set a dc offset voltage 21 To set the duty cycle 22 To output a stored arbitrary waveform 23 To output a dc voltage 24 To store the instrument state 25 To rack mount the function generator 27

Chapter 2 Front-Panel Menu Operation

Front-panel menu reference 31 A front-panel menu tutorial 33 To select the output termination 40 To output a modulated waveform 41 To output an FSK waveform 44 To output a burst waveform 47 To output a frequency sweep 49 To trigger a burst or sweep 51 To turn off the comma separator 52

Contents

Chapter 3 Features and Functions

Output Configuration 55 Amplitude Modulation (AM) 71 Frequency Modulation (FM) 76 Burst Modulation 81 Frequency-Shift Keying (FSK) Modulation 90 Frequency Sweep 94 Triggering 98 Arbitrary Waveforms 103 System-Related Operations 109 Remote Interface Configuration 114 Calibration Overview 118 Power-On and Reset State 123

Contents

Chapter 4 Remote Interface Reference

SCPI Command Summary 127 Simplified Programming Overview 136 Using the APPLy Command 138 Output Configuration Commands 145 AM Modulation Commands 154 FM Modulation Commands 157 Burst Modulation Commands 160 Frequency-Shift Keying (FSK) Commands 167 Frequency Sweep Commands 170 Arbitrary Waveform Commands 174 Triggering 186 System-Related Commands 188 Calibration Commands 193 RS-232 Interface Configuration 195 RS-232 Interface Commands 200 The SCPI Status Registers 201 Status Reporting Commands 209 An Introduction to the SCPI Language 211 Halting an Output in Progress 216 To set the HP-IB address 217 To select the remote interface 218 To set the baud rate 219 To set the parity 220 SCPI Conformance Information 221 IEEE-488 Conformance Information 225

Chapter 5 Error Messages

Execution Errors 229 Self-Test Errors 237 Calibration Errors 238 Arbitrary Waveform Errors 240

Contents

Chapter 6 Application Programs

HP BASIC Programs 244 C Language Programs 244 QuickBASIC Language Programs 247 Using the APPLy Command 248 Using the Low-Level Commands 252 Downloading an Arbitrary Waveform over HP-IB 255 Using the Status Registers 261 Downloading an Arbitrary Waveform over RS-232 267

Chapter 7 Tutorial

Direct Digital Synthesis 273 Signal Imperfections 276 Creating Arbitrary Waveforms 278 Output Amplitude Control 280 Floating Signal Generators 282 Attributes of AC Signals 283 Modulation 287

Contents

Chapter 8 Specifications

Frequency Characteristics 298 Sinewave Spectral Purity 298 Signal Characteristics 298 Output Characteristics 298 Modulation Characteristics 299 Frequency Sweep 299 System Characteristics 299 General Specifications 300 Product Dimensions 301

Index 303

Declaration of Conformity 309

Quick Start

One of the first things you will want to do with your function generator is to become acquainted with its front panel. We have written the exercises in this chapter to prepare the function generator for use and help you get familiar with some of the front-panel operations.

The front panel has two rows of keys to select various functions and operations. Most keys have a shifted function printed in blue above the key. To perform a shifted function, press ciator will turn on). Then, press the key that has the desired label above it. For example, to select the function, press

Shift AM (the shifted version of the key).

AM (amplitude modulation)

Shift (the Shift annun-

If you accidentally press

Shift annunciator.

Shift , just press it again to turn off the

Most keys also have a number printed in green next to the key. To enable the number mode, press

Enter Number (the Num annunciator

will turn on). Then, press the keys that have the desired numbers

printed next to them. For example, to select the number “10”,

Enter Number 1 0 (next to the and Recall keys).

press

If you accidentally press

Enter Number , just press Shift Cancel

to turn off the Num annunciator.

Chapter 1 Quick Start

To prepare the function generator for use

The following steps help you verify that the function generator is ready for use.

1 Check the list of supplied items.

Verify that you have received the following items with your function generator. If anything is missing, contact your nearest Hewlett-Packard Sales Office.

One power cord.

This User’s Guide.

One Service Guide.

One folded Quick Reference card.

Certificate of Calibration.

2 Connect the power cord and turn on the function generator.

The front-panel display will light up while the function generator performs its power-on self-test. The Notice that the function generator powers up in the sine wave function

at 1 kHz with an amplitude of 100 mV peak-to-peak (into a 50Ω

termination).

To review the power-on display with all annunciators turned on, hold down

3Perform a complete self test.

The complete self-test performs a more extensive series of tests than those performed at power-on. Hold down switch to turn on the function generator; hold down the key for more than 5 seconds. The self-test will begin when you release the key.

If the self-test is successful, “ If the self-test is not successful, “ annunciator turns on. See the Service Guide for instructions on returning the function generator to Hewlett-Packard for service.

Shift as you turn on the function generator.

PASS” is displayed on the front panel.

HP-IB bus address is displayed.

Shift as you press the Power

FAIL” is displayed and the ERROR

Chapter 1 Quick Start

If the function generator does not turn on

Use the following steps to help solve problems you might experience when turning on the function generator. If you need more help, see the Service Guide for instructions on returning the function generator to Hewlett-Packard for service.

1 Verify that there is ac power to the function generator.

First, verify that the function generator’s Power switch is in the “On” position. Also, make sure that the power cord is firmly plugged into to the power module on the rear panel. You should also make sure that the power source you plugged the function generator into is energized.

2 Verify the power-line voltage setting.

The line voltage is set to the proper value for your country when the function generator is shipped from the factory. Change the voltage setting if it is not correct. The settings are: 100, 120, 220, or 240 Vac (for 230 Vac operation, use the 220 Vac setting).

See the next page if you need to change the line-voltage setting.

3 Verify that the power-line fuse is good.

The function generator is shipped from the factory with a 500 mAT fuse installed. This is the correct fuse for all line voltages.

See the next page if you need to change the power-line fuse.

To replace the 500 mAT fuse, order HP part number 2110-0458.

Chapter 1 Quick Start

If the function generator does not turn on

1 Remove the power cord. Remove the

fuse-holder assembly from the rear panel.

3 Rotate the line-voltage selector until the

correct voltage appears in the window.

2 Remove the line-voltage selector from

the assembly.

Fuse: 500 mAT (for all line voltages) HP Part Number: 2110-0458

4 Replace the fuse-holder assembly in the rear panel.

100, 120, 220 (230), or 240 Vac

Verify that the correct line voltage is selected and the power-line fuse is good.

Chapter 1 Quick Start

To adjust the carrying handle

To adjust the position, grasp the handle by the sides and pull outward. Then, rotate the handle to the desired position.

Bench-top viewing positions Carrying position

Chapter 1 Quick Start

To set the output frequency

At power-on, the function generator outputs a sine wave at 1 kHz with

an amplitude of 100 mV peak-to-peak (into a 50Ω termination).

The following steps show you how to change the frequency to 1.2 MHz.

Freq

Enter Number

∧

MHz m Vpp

1 Enable the frequency modify mode.

The displayed frequency is either the power-on value or the previous frequency selected. When you change functions, the same frequency is used if the present value is valid for the new function.

1.000,000,0 KHz

2 Enter the magnitude of the desired frequency.

Notice that the Num annunciator turns on and “ENTER NUM” flashes on

the display, indicating that the number mode is enabled.

1.2

To cancel the number mode, press

Shift Cancel .

3 Set the units to the desired value.

The units are selected using the arrow keys on the right side of the front panel. As soon as you select the units, the function generator outputs the waveform with the displayed frequency. To turn off the

flashing digit, move the cursor to the left of the display using the arrow keys.

1.200,000,0 MHz

You can also use the knob and arrow keys to enter a number.

See “Front-Panel Number Entry” on page 3 for more information.

Chapter 1 Quick Start

To set the output amplitude

At power-on, the function generator outputs a sine wave with an

amplitude of 100 mV peak-to-peak (into a 50Ω termination).

The following steps show you how to change the amplitude to 50 mVrms.

Ampl

Enter Number 5

Shift

kHz

∨

m Vrms

1 Enable the amplitude modify mode.

The displayed amplitude is either the power-on value or the previous amplitude selected. When you change functions, the same amplitude is used if the present value is valid for the new function.

100.0 mVPP

2 Enter the magnitude of the desired amplitude.

Notice that the Num annunciator turns on and “ENTER NUM” flashes on

the display, indicating that the number mode is enabled.

To cancel the number mode, press

Shift Cancel .

3 Set the units to the desired value.

The units are selected using the arrow keys on the right side of the front panel. As soon as you select the units, the function generator outputs the waveform with the displayed amplitude. To turn off the

flashing digit, move the cursor to the left of the display using the arrow keys.

50.00 mVRMS

You can also use the knob and arrow keys to enter a number.

See “Front-Panel Number Entry” on page 3 for more information.

Chapter 1 Quick Start

To set a dc offset voltage

At power-on, the function generator outputs a sine wave with a dc offset

voltage of 0 volts (into a 50Ω termination). The following steps show you

how to change the offset to –1.5 mVdc.

Offset

Enter Number ±

Shift ∨

kHz m Vrms

1 Enable the offset modify mode.

The displayed offset voltage is either the power-on value or the previous offset selected. When you change functions, the same offset is used if the present value is valid for the new function.

+0.000 VDC

2 Enter the magnitude of the desired offset.

Notice that the Num annunciator turns on and “ENTER NUM” flashes on the display, indicating that the number mode is enabled. Notice that

toggles the displayed value between + and – .

-1.5

To cancel the number mode, press

Shift Cancel .

3 Set the units to the desired value.

At this point, the function generator outputs the waveform with the displayed offset. Notice that the

Offset annunciator turns on, indicating

that the waveform is being output with an offset. The annunciator will turn on when the offset is any value other than 0 volts. To turn off the

flashing digit, move the cursor to the left of the display using the arrow keys.

-01.50 mVDC

You can also use the knob and arrow keys to enter a number.

See “Front-Panel Number Entry” on page 3 for more information.

Chapter 1 Quick Start

To set the duty cycle

Applies only to square waves. At power-on, the duty cycle for square waves is 50%. You can adjust the duty cycle for a square waveform from 20% to 80%, in increments of 1% (for frequencies above 5 MHz, the range is 40% to 60%). The following steps show you how to change the

duty cycle to 45%.

% Duty Shift

Enter Number

Enter

1 Select the square wave function.

Notice that the annunciator turns on, indicating that the square wave function is enabled.

2 Enable the duty cycle modify mode.

The displayed duty cycle is either the power-on value or the previous value selected.

50 % DUTY

This message appears on the display for approximately 10 seconds. Repeat this step as needed.

3 Enter the desired duty cycle.

Notice that the Num annunciator turns on and “ENTER NUM” flashes on

the display, indicating that the number mode is enabled.

To cancel the number mode, press

Shift Cancel .

4 Output the waveform with the displayed duty cycle.

45 % DUTY

You can also use the knob and arrow keys to enter a number.

See “Front-Panel Number Entry” on page 3 for more information.

Chapter 1 Quick Start

To output a stored arbitrary waveform

There are five built-in arbitrary waveforms stored in non-volatile memory for your use. You can output these waveforms directly from non-volatile memory. The following steps show you how to output an

“exponential rise” waveform from memory.

Shift

Enter

Arb List

1 Display the list of arbitrary waveforms.

The list contains the five built-in arbitrary waveforms (sinc, negative ramp, exponential rise, exponential fall, and cardiac). The list may also contain up to four user-defined arbitrary waveform names. The first

choice on this level is “

SINC”.

SINC

This message appears on the display for approximately 10 seconds. Repeat this step as needed.

2 Move across to the

EXP_RISE choice.

EXP_RISE

3 Select and output the displayed arbitrary waveform.

Notice that the

Arb annunciator turns on, indicating that the output is

an arbitrary waveform. The waveform is output using the present settings for frequency, amplitude, and offset unless you change them.

The selected waveform is now assigned to the

Arb key. Whenever

you press this key, the selected arbitrary waveform is output.

You can also use the knob to scroll left or right through the choices in the list.

See “Front-Panel Number Entry” on page 3 for more information.

Chapter 1 Quick Start

To output a dc voltage

In addition to generating waveforms, you can also output a dc voltage in

the range ± 5 Vdc (into a 50Ω termination). The following steps show

you how to output +155 mVdc.

Enter Number

5 1

Shift

kHz

∨

m Vrms

1 Press the key and hold it down for more than 2 seconds.

To enter the dc voltage mode, press the top row of function keys and

Offset

Offset key or any key in the

hold it down for more than 2 seconds.

The displayed voltage is either the power-on value or the previous offset voltage selected.

DCV

+0.000 VDC

2 Enter the magnitude of the desired voltage.

Notice that the Num annunciator turns on and “ENTER NUM” flashes on

the display, indicating that the number mode is enabled.

155

To cancel the number mode, press

Shift Cancel .

3 Set the units to the desired value.

At this point, the function generator outputs the displayed dc voltage. Notice that the

Offset annunciator turns on (all other annunciators

are off), indicating that a dc voltage is being output. The annunciator will turn on when the offset is any value other than 0 volts.

+155.0 mVDC

You can also use the knob and arrow keys to enter a number.

See “Front-Panel Number Entry” on page 3 for more information.

Chapter 1 Quick Start

To store the instrument state

You can store up to three different instrument states in non-volatile memory. This enables you to recall the entire instrument configuration with just a few key presses from the front panel. The following steps

show you how to store and recall a state.

1 Set up the function generator to the desired configuration.

The state storage feature “remembers” the function, frequency, amplitude, dc offset, duty cycle, as well as any modulation parameters.

∧

Enter

Store Shift

2 Turn on the state storage mode.

Three memory locations (numbered 1, 2, and 3) are available to store instrument configurations. The instrument configuration is stored in non-volatile memory and is remembered when power has been off.

STORE 1

This message appears on the display for approximately 10 seconds. Repeat this step as needed.

3 Store the instrument state in memory location “2”.

Use the up and down arrow keys to select the memory location.

STORE 2

To cancel the store operation, press

Shift Store again or let the

display time-out after 10 seconds.

4 Save the instrument state.

The instrument state is now stored. To recall the stored state, turn to the next page.

You can also use the knob or “enter number” mode to enter a memory location.

See “Front-Panel Number Entry” on page 3 for more information.

Chapter 1 Quick Start

To store the instrument state

To verify that the state was stored properly, you can turn the power off before recalling the state.

Recall

Enter

5 Recall the stored instrument state.

To recall the stored state, you must use the same memory location used previously to store the state. Use the up and down arrow keys to change the displayed storage location.

RECALL 2

To cancel the restore operation, press

Recall again.

This message appears on the display for approximately 10 seconds. Repeat this step as needed.

6 Restore the instrument state.

The function generator should now be configured in the same state as when you stored the setup on the previous page.

When power is turned off, the function generator automatically stores

its state in memory location “0”. You can recall the power-down state, but you cannot store the state to location “0” from the front panel.

Use the POWER ON LAST STATE command in the SYS MENU to automatically recall the power-down state when power is turned on. See chapter 2 for more information on using the front-panel menus.

Chapter 1 Quick Start

To rack mount the function generator

You can mount the function generator in a standard 19-inch rack cabinet using one of three optional kits available. Instructions and mounting hardware are included with each rack-mounting kit.

HP System II instrument of the same size can be rack-mounted

Any beside the HP 33120A Function Generator.

Remove the carrying handle, and the front and rear rubber bumpers, before rack-mounting the function generator.

To remove the handle, rotate it to the vertical position and pull the ends outward.

Front Rear (bottom view)

To remove the rubber bumper, stretch a corner and then slide it off.

Chapter 1 Quick Start

To rack mount the function generator

To rack mount a single instrument, order adapter kit 5063- 9240.

To rack mount two instruments side-by-side, order lock-link kit 5061-9694 and flange kit 5063- 9212.

To instal l one or two instr uments in a slidin g support shelf, or der shelf 5063-9 255, and slide kit 1494-0015 (for a single instrument, also order filler panel 5002-3999).

Front-Panel Menu Operation

By now you should be familiar with some of the basic features of the front panel. Chapter 1 shows you how to prepare the function generator for use and describes a few of the front-panel features. If you are not familiar with this information, we recommend that you read chapter 1,

“Quick Start,” starting on page 13.

Chapter 2 introduces you to the use of the front-panel menu. This chapter does not give a detailed description of every front-panel key or menu operation. It does, however, give you a good overview of the front-panel menu and many front-panel operations. See chapter 3 “Features and Functions,” starting on page 53, for a complete discussion of the function generator’s capabilities and operation.

If you purchased the Phase-Lock Option for the HP 33120A, an additional menu

For information on using the Phase-Lock Option, refer to the User’s and Service Guide included with Option 001.

(G: PHASE MENU) is available from the front panel.

Chapter 2 Front-Panel Menu Operation

Front-panel menu reference

A: MODulation MENU

1: AM SHAPE  2: AM SOURCE  3: FM SHAPE  4: BURST CNT  5: BURST RATE 

 6: BURST PHAS  7: BURST SRC  8: FSK FREQ  9: FSK RATE  10: FSK SRC

1: AM SHAPE 2: AM SOURCE 3: FM SHAPE 4: BURST CNT 5: BURST RATE 6: BURST PHAS 7: BURST SRC 8: FSK FREQ 9: FSK RATE 10: FSK SRC

Selects the shape of the AM modulating waveform. Enables or disables the internal AM modulating source. Selects the shape of the FM modulating waveform. Sets the number of cycles per burst (1 to 50,000 cycles). Sets the burst rate in Hz for an internal burst source. Sets the starting phase angle of a burst (-360 to +360 degrees). Selects an internal or external gate source for burst modulation.

Sets the FSK “hop” frequency. Selects the internal FSK rate between the carrier and FSK frequency. Selects an internal or external source for the FSK rate.

B: SWP (Sweep) MENU

1: START F  2: STOP F  3: SWP TIME  4: SWP MODE

1: START F 2: STOP F 3: SWP TIME 4: SWP MODE

C: EDIT MENU

1: NEW ARB  [ 2: POINTS ]  [ 3: LINE EDIT ]  [ 4: POINT EDIT ]  [ 5: INVERT ]  [ 6: SAVE AS ]  7: DELETE

Sets the start frequency in Hz for sweeping. Sets the stop frequency in Hz for sweeping. Sets the repetition rate in seconds for sweeping. Selects linear or logarithmic sweeping.

1: NEW ARB 2: POINTS 3: LINE EDIT 4: POINT EDIT 5: INVERT 6: SAVE AS 7: DELETE

The commands enclosed in square brackets ( [ ] ) are “hidden” until you make a selection from the NEW ARB command

to initiate a new edit session.

Initiates a new arb waveform or loads the selected arb waveform. Sets the number of points in a new arb waveform (8 to 16,000 points). Performs a linear interpolation between two points in the arb waveform. Edits the individual points of the selected arb waveform. Inverts the selected arb waveform by changing the sign of each point. Saves the current arb waveform in non-volatile memory. Deletes the selected arb waveform from non-volatile memory.

Chapter 2 Front-Panel Menu Operation

Front-panel menu reference

D: SYStem MENU

1: OUT TERM  2: POWER ON  3: ERROR  4: TEST  5: COMMA  6: REVISION

1: OUT TERM 2: POWER ON 3: ERROR 4: TEST 5: COMMA 6: REVISION

Selects the output termination (50 Enables or disables automatic recall of the power-down state. Retrieves errors from the error queue (up to 20 errors). Performs a complete self-test. Enables or disables a comma separator between digits on the display.

Displays the function generator’s firmware revision codes.

Ω or high impedance).

E: Input / Output MENU

1: HPIB ADDR  2: INTERFACE  3: BAUD RATE  4: PARITY  5: LANGUAGE

1: HPIB ADDR 2: INTERFACE 3: BAUD RATE 4: PARITY 5: LANGUAGE

F: CALibration MENU

1: SECURED  [ 1: UNSECURED ]  [ 2: CALIBRATE ]  3: CAL COUNT  4: MESSAGE

1: SECURED 1: UNSECURED 2: CALIBRATE 3: CAL COUNT 4: MESSAGE

Sets the HP-IB bus address (0 to 30). Selects the HP-IB or RS-232 interface. Selects the baud rate for RS-232 operation. Selects even, odd, or no parity for RS-232 operation. Verifies the interface language: SCPI.

The function generator is secured against calibration; enter code to unsecure. The function generator is unsecured for calibration; enter code to secure. Performs individual calibrations; must be UNSE CURED. Reads the total number of times the function generator has been calibrated. Reads the calibration string (up to 11 characters) entered from remote.

The commands enclosed in square brackets ( [ ] ) are “hidden” unless the function generator is UNSECURED for calibration.

Chapter 2 Front-Panel Menu Operation

A front-panel menu tutorial

This section is a step-by-step tutorial which shows you how to use the front-panel menu. We recommend that you spend a few minutes with this tutorial to get comfortable with the structure and operation of the menu.

The menu is organized in a top-down tree structure with three levels (menus, commands, and parameters). You move down or up

∧ the menu tree to get from one level to the next. Each of the

three levels has several horizontal choices which you can view by moving left

< or right > .

∨

Commands

Parameters

Menus

The menu is organized in a top-down tree structure with three levels.

• To turn on the menu, press

• To turn off the menu, press

• To execute a menu command, press

Shift Menu On/Off .

Enter .

• To recall the last menu command that was executed,

Shift Recall Menu .

press

• To turn off the menu at any time without saving changes,

Shift Cancel .

press

Chapter 2 Front-Panel Menu Operation

A front-panel menu tutorial

Messages Displayed During Menu Use

TOP OF MENU You pressed while on the “MENUS” level; this is the top level of the

∧

menu and you cann ot go an y hi gh er.

Shift

To turn off the menu, press . To move across the choices on a level, pre ss or . To move down a level, press .

MENUS You are on the “MENUS” level. Press or to view the choices. COMMANDS You are on the “COMMANDS” level. Press or to view the command

Menu On/Off

∨

choices within the selected menu group.

PARAMETER You are on the “PARAMETER” level. Press or to view and edit the

parameter for the selected command.

MENU BOTTOM You pressed while on the “PARAMETER ” level; this is the bottom

∨

level of the menu and you cannot go any lower.

Menu On/Off

To turn off the menu, press . To move up a level, press .

ENTERED The change made on the “PARAMETER” level is saved. This is displayed after

you press (Menu Enter) to execute the command.

MIN VALUE The value you specified on the “PARAMETER” level is too small for the

Enter

Shift

∧

selected command. The minimum value allowed is displayed for you to edit.

MAX VALUE The value you specified on the “PARAMETER” level is too larg e fo r the

selected comma nd. The maximum value allowed is displayed for you to edit.

EXITING You will see this message if you turn off the menu by pressing

Menu On/Off Shift Cancel

Shift

or . You did not edit any values on the “PARAMETER” level and changes were NOT sa ve d.

NOT ENTERED You will see this message if you turn off the menu by pressing

Shift

Menu On/Off

or . You did some editing of parameters but the changes were NOT saved. Press the key (Menu Enter) to save changes made on the “

PARAMETER” level.

Shift

Cancel

Enter

Chapter 2 Front-Panel Menu Operation

A front-panel menu tutorial

Menu Example 1 The following steps show you how to turn on the menu, move up and

down between levels, move across the choices on each level, and turn off the menu. In this example, you will enable the function generator to

automatically recall the power-down state when power is turned on.

Shift Menu On/Off

∨

1 Turn on the menu.

You enter the menu on the “

MENUS” level. The MOD MENU is your first

choice on this level.

A: MOD MENU

Move across to the

SYS MENU choice on this level.

There are six menu group choices available on the “MENUS” level. Each choice has a letter prefix for easy identification (

A: , B: , etc.).

D: SYS MENU

3 Move down to the “

OUT TERM command is your first choice on this level.

The

COMMANDS” level within the SYS MENU.

1: OUT TERM

4 Move across to the

POWER ON command on this level.

There are six command choices available in the SYS MENU. Each choice on this level has a number prefix for easy identification (

1: , 2: , etc.).

2: POWER ON

You can also use the knob to scroll left or right through the choices on each

level of the menu.

Chapter 2 Front-Panel Menu Operation

A front-panel menu tutorial

∨

Enter

5 Move down a level to the “PARAMETER” choices.

The first parameter choice is “

DEFAULT” is the factory setting and is stored in non-volatile memory).

(“

DEFAULT” for the POWER ON command

DEFAULT

6 Move across to the

“LAST STATE” choice.

There are two parameter choices for POWER ON.

LAST STATE

7 Save the change and turn off the menu.

The function generator beeps and displays a message to show that the change is now in effect. You are then exited from the menu.

ENTERED

You can also use the knob to scroll left or right through the choices on each

level of the menu.

Chapter 2 Front-Panel Menu Operation

A front-panel menu tutorial

Menu Example 2 The following example shows how to use the recall menu feature as a

shortcut to set the

POWER ON command back to its original setting.

You must perform the steps in Example 1 before you start this example.

Shift <

Recall Menu

1 Use recall menu to return to the

This returns you to the

POWER ON command, which was the last

POWER ON command.

command used before you exited the menu in the Example 1.

2: POWER ON

∨

Enter

2 Move down to the “

The first parameter choice is “

PARAMETER” choices.

LAST STATE” (the current setting from

Example 1).

LAST STATE

Move across to the

“DEFAULT” choice.

Set the parameter back to its original value.

DEFAULT

4 Save the change and turn off the menu.

The function generator beeps and displays a message to show that the change is now in effect. You are then exited from the menu.

ENTERED

You can also use the knob to scroll left or right through the choices on each

level of the menu.

Chapter 2 Front-Panel Menu Operation

A front-panel menu tutorial

Menu Example 3 Some commands in the menu require that you enter a numeric

parameter value. The following steps show you how to enter a number in the menu. For this example, you will set the number of cycles for the

burst modulation mode.

Shift Menu On/Off

∨

> > >

1 Turn on the menu.

You enter the menu on the “

MENUS” level. The MOD MENU is your first

choice on this level.

A: MOD MENU

2 Move down to the “

AM SHAPE command is your first choice on this level.

The

COMMANDS” level within the MOD MENU.

1: AM SHAPE

3 Move across to the

BURST CNT command on this level.

There are ten command choices available in the MOD MENU.

4: BURST CNT

You can also use the knob to scroll left or right through the choices on each

level of the menu.

Chapter 2 Front-Panel Menu Operation

A front-panel menu tutorial

∨

∧

4 Move down a level to edit the BURST CNT parameter.

The number of cycles should be “1” when you come to this point in the menu for the first time. For this example, you will set the number of cycles to “4”. Notice that the

Burst annunciator flashes, indicating that

the displayed value is for the burst mode.

∧00001 CYC

When you see the flashing “∧” on the left side of the display, you can

press

∧ to abort the edit and return to the “COMMANDS” level.

5 Move the flashing cursor over to edit the last digit.

Notice that the rightmost digit is flashing (the digit wraps around).

00001 CYC

6 Increment the last digit until “4” is displayed.

You decrement or increment each digit independently.

Enter

00004 CYC

7 Save the change and turn off the menu.

The function generator beeps and displays a message to show that the change is now in effect. You are then exited from the menu.

ENTERED

You can also use the knob or “enter number” mode to enter a number.

See “Front-Panel Number Entry” on page 3 for more information.

Chapter 2 Front-Panel Menu Operation

To select the output termination

The function generator has a fixed output impedance of 50 ohms on the OUTPUT terminal. You can specify whether you are terminating the output into a 50 between the source and load will result in an output amplitude or dc offset which does not match the specified value.

Ω load or an open circuit. Incorrect impedance matching

Shift Menu On/Off

> > >

∨

1 Turn on the menu.

A: MOD MENU

2 Move across to the SYS MENU choice on this level.

D: SYS MENU

3 Move down a level to the

OUT TERM command.

1: OUT TERM

4 Move down a level and then across to the

HIGH Z choice.

With the output termination set to “HIGH Z”, the function generator allows you to set the unloaded (open circuit) output voltage.

HIGH Z

Enter

5 Save the change and turn off the menu.

The function generator beeps and displays a message to show that the change is now in effect. You are then exited from the menu.

You can also use the knob to scroll left or right through the choices on each

level of the menu.

Chapter 2 Front-Panel Menu Operation

To output a modulated waveform

A modulated waveform consists of a carrier and a modulating waveform. In is varied by the amplitude of the modulating waveform. For this

example, you will output an AM waveform with 80% modulation depth. The carrier will be a 5 kHz sine wave and the modulating waveform will be a 200 Hz sine wave.

AM (amplitude modulation), the amplitude of the carrier

Shift <

Recall Menu

1 Select the function, frequency, and amplitude of the carrier.

For the carrier waveform, you can select a sine, square, triangle, ramp, or arbitrary waveform. For this example, select a

an amplitude of

AM Shift

2 Select AM.

Notice that the

5 Vpp.

AM annunciator turns on.

5 kHz sine wave with

3 Use the menu to select the shape of the modulating waveform.

After you enable the

automatically take you to the

AM function, the “recall menu” key will

AM SHAPE command in the MOD MENU.

1: AM SHAPE

Chapter 2 Front-Panel Menu Operation

To output a modulated waveform

∨

Enter

4 Move down a level and verify that “SINE” is selected.

For the modulating waveform, you can select a sine, square, triangle, ramp, noise, or arbitrary waveform. For this example, you will modulate the carrier with a sine waveform. Notice that the flashes, indicating that the displayed parameter is for

AM annunciator

AM.

SINE

5 Save the change and turn off the menu.

The modulating waveform is now a sine waveform.

ENTERED

Freq Shift

6 Set the modulating frequency to 200 Hz.

Notice that the frequency is the modulating frequency for

AM annunciator flashes, indicating that the displayed

AM. Also notice that the

modulating frequency is displayed with fewer digits than the carrier frequency. For more information on editing numbers in the menu,

refer to “Menu Example 3” earlier in this chapter.

MOD 200.0 Hz

This message appears on the display for approximately 10 seconds. Repeat this step as needed.

Chapter 2 Front-Panel Menu Operation

To output a modulated waveform

Shift

Level

7 Set the modulation depth to 80%.

Notice that the percentage is the

080 % DEPTH

This message appears on the display for approximately 10 seconds. Repeat this step as needed.

At this point, the function generator outputs the specified modulation parameters.

AM annunciator flashes, indicating that the displayed

AM depth (also called percent modulation).

AM waveform with the

Chapter 2 Front-Panel Menu Operation

To output an FSK waveform

You can configure the function generator to “shift” its output frequency between two preset values using The rate at which the output shifts between the two frequencies (called the “carrier frequency” and the “hop frequency”) is determined by the internal rate generator or the signal level on the rear-panel FSK terminal. For this example, you will set the “carrier” frequency to 3 kHz and

the “hop” frequency to 500 Hz, with an FSK rate of 100 Hz.

FSK (frequency-shift keying) modulation.

Shift

Recall Menu

FSK

1 Select the function, frequency, and amplitude of the carrier.

For the carrier waveform, you can select a sine, square, triangle, ramp, or arbitrary waveform. For this example, select a

an amplitude of

5 Vpp.

3 kHz sine wave with

2 Enable FSK.

Notice that the

FSK annunciator turns on.

3 Use the menu to set the “hop” frequency.

After you enable the

take you to the

8: FSK FREQ

FSK mode, the “recall menu” key will automatically

FSK FREQ command in the MOD MENU.

Chapter 2 Front-Panel Menu Operation

To output an FSK waveform

∨

Enter

Shift <

Recall Menu

4 Move down a level and set the “hop” frequency to 500 Hz.

Notice that the parameter is for the

FSK annunciator flashes, indicating that the displayed

FSK mode. Also notice that the hop frequency is

displayed with fewer digits than the carrier frequency. For more

information on editing numbers in the menu, refer to “Menu Example 3” earlier in this chapter.

∧500.0 Hz

5 Save the change and turn off the menu.

At this point, the carrier and hop frequencies are set and output.

Now, we will go back into the menu to set the FSK “shift” rate — this is the rate at which the function generator shifts between the carrier frequency and hop frequency.

6 Use the menu to set the

The “recall menu” key returns you to the

FSK “shift” rate.

FSK FREQ command, which

was the last command used before you exited the menu.

8: FSK FREQ

Chapter 2 Front-Panel Menu Operation

To output an FSK waveform

∨

Enter

7 Move across to the FSK RATE command.

9: FSK RATE

8 Move down a level and set the

Notice that the parameter is for the

FSK annunciator flashes, indicating that the displayed

FSK mode. For more information on editing

FSK “shift” rate to 100 Hz.

numbers in the menu, refer to “Menu Example 3” earlier in this chapter.

∧100.0 Hz

9 Save the change and turn off the menu.

The function generator beeps and displays a message to show that the change is now in effect. You are then exited from the menu.

ENTERED

At this point, the function generator outputs the

FSK waveform.

You can also use an external signal to shift between the carrier frequency and hop frequency. For more information, see “Frequency-Shift Keying (FSK) Modulation” in chapter 3.

Chapter 2 Front-Panel Menu Operation

To output a burst waveform

You can configure the function generator to output a waveform with a specified number of cycles, called a burst. You can output the burst at a rate determined by the internal rate generator or the signal level on the rear-panel Ext Trig terminal. For this example, you will output a

three-cycle sine wave. You will not change the other parameters from their default settings: internal burst source, 0 degree starting phase, and 100 Hz burst rate.

Shift

Shift <

Recall Menu

Burst

1 Select the function, frequency, and amplitude for the burst.

For bursts, you can select sine, square, triangle, ramp, or arbitrary waveforms. For this example, select a

amplitude of

5 Vpp.

1 kHz sine wave with an output

2 Enable the burst mode.

Notice that the

Burst annunciator turns on.

3 Use the menu to set the burst count.

After you enable the burst mode, the “recall menu” key will automatically take you to the

BURST CNT command in the MOD MENU.

4: BURST CNT

Chapter 2 Front-Panel Menu Operation

To output a burst waveform

∨

Enter

4 Move down to the parameter level and set the count to “3”.

Notice that the

Burst annunciator flashes, indicating that the displayed

parameter is for the burst mode. For more information on editing

numbers in the menu, refer to “Menu Example 3” earlier in this chapter.

∧00003 CYC

You can also select an infinite burst count. Press the right or left arrow keys until the “ to display “

CYC” units are flashing. Then, press the down arrow key

INFINITE”.

5 Save the change and turn off the menu.

The function generator beeps and displays a message to show that the change is now in effect. You are then exited from the menu.

ENTERED

At this point, the function generator outputs a continuous three-cycle burst.

You can generate a single burst (with the specified burst count) by pressing the “Single” key from the front panel or applying a trigger pulse to the rear-panel Ext Trig terminal. For more information, see “To trigger a burst or sweep” on page 51.

You can also use an external gate signal to turn the output signal on and off. For more information, see “Burst Modulation” in chapter 3.

Chapter 2 Front-Panel Menu Operation

To output a frequency sweep

from 50 Hz to 5 kHz. You will not change the other parameters from their default settings: internal sweep trigger, linear spacing, and 1 second sweep time.

Shift

Shift <

Recall Menu

Sweep

1 Select the function and amplitude for the sweep.

For sweeps, you can select sine, square, triangle, ramp, or arbitrary waveforms. For this example, select a sine wave with a

5 Vpp amplitude.

2 Enable the sweep mode.

Notice that the

Swp annunciator turns on.

3 Use the menu to select the start frequency.

After you enable the sweep mode, the “recall menu” key will automatically take you to the

START F command in the SWP MENU.

1: START F

Chapter 2 Front-Panel Menu Operation

To output a frequency sweep

∨

Enter

Shift <

Recall Menu

4 Move down a level and set the start frequency to 50 Hz.

Notice that the

Swp annunciator flashes, indicating that the displayed

parameter is for the sweep mode. For more information on editing

numbers in the menu, refer to “Menu Example 3” earlier in this chapter.

∧50.00 Hz

5 Save the change and turn off the menu.

The start frequency is now set to 50 Hz.

6 Use recall menu to return to the

The “recall menu” key returns you to the

START F command.

START F command, which was

the last command used before you exited the menu.

1: START F

7 Move across to the

STOP F command.

2: STOP F

∨

Enter

8 Move down a level and set the stop frequency to 5 kHz.

∧5.000 KHz

9 Save the change and turn off the menu.

At this point, the function generator outputs a continuous sweep from 50 Hz to 5 kHz.

You can generate one frequency sweep by pressing the “Single” key or applying a trigger pulse to the rear-panel Ext Trig terminal. For more information, see “To trigger a burst or sweep” on the next page.

Chapter 2 Front-Panel Menu Operation

To trigger a burst or sweep

You can issue triggers from the front-panel for burst modulation and frequency sweeps using single trigger or internal trigger.

Enables single trigger and triggers the generator.

Enables internal trigger.

Trig annunciator is on when the generator is waiting for single trigger (internal trigger disabled).

• Internal or “automatic” triggering is enabled when you turn on the

function generator. In this mode, the function generator outputs continuously when burst modulation or sweep is selected.

• Single triggering outputs one burst or initiates one frequency sweep

each time you press

Single . Continue pressing this key to re-trigger

the function generator.

• Pressing

Single to enable the single trigger mode also enables the

external trigger mode. External triggering is like the single trigger

mode except that you apply a trigger signal to the rear-panel Ext Trig terminal. The function generator is triggered on the rising edge of a

TTL pulse.

• The

Single key is disabled when in remote (the Rmt annunciator

turns on when in remote) and when a function other than burst modulation or sweep is selected.

Chapter 2 Front-Panel Menu Operation

To turn off the comma separator

The function generator can display values on the front panel with or without a comma separator. The following steps show how to turn off the comma separator.

Shift Menu On/Off

> >

∨

∨ >

15.000,000 MHz

With comma separator Without comma separator

(factory setting)

15.000000 MHz

1 Turn on the menu.

A: MOD MENU

2 Move across to the

SYS MENU choice on the “MENUS” level.

D: SYS MENU

< <

3 Move down a level and then across to the

COMMA command.

5: COMMA

4 Move down a level and then across to the “

OFF” choice.

Enter

OFF

5 Save the change and turn off the menu.

The comma separator setting is stored in non-volatile memory, and does not change when power has been off or after a remote interface reset.

Features and Functions

You will find that this chapter makes it easy to look up all the details about a particular feature of the function generator. Whether you are operating the function generator from the front panel or over the remote interface, this chapter will be useful. This chapter is divided into the following sections:

Output Configuration, starting on page 55

•

Amplitude Modulation (AM), starting on page 71

•

Frequency Modulation (FM), starting on page 76

•

Burst Modulation, starting on page 81

•

Frequency-Shift Keying (FSK) Modulation, starting on page 90

•

Frequency Sweep, starting on page 94

•

Triggering, starting on page 98

•

Arbitrary Waveforms, starting on page 103

•

System-Related Operations, starting on page 109

•

Remote Interface Configuration, starting on page 114

•

Calibration Overview, starting on page 118

•

Power-On and Reset State, on page 123

•

Some knowledge of the front-panel menu will be helpful before you read

this chapter. If you have not already read chapter 2, “Front-Panel Menu Operation,” starting on page 29, you may want to read it now. Chapter 4, “Remote Interface Reference,” starting on page 125, lists the syntax for

SCPI commands available to program the function generator.

the

Throughout this manual, the following conventions are used for

SCPI command syntax for remote interface programming.

• Square brackets ( [ ] ) indicate optional keywords or parameters.

• Braces ( { } ) enclose parameters within a command string.

• Triangle brackets ( < > ) indicate that you must substitute a value

for the enclosed parameter.

• A vertical bar (

) separates multiple parameter choices.

Chapter 3 Features and Functions

Output Configuration

This section contains information to help you configure the function generator for outputting waveforms. You may never have to change some of the parameters discussed here, but they are provided to give you the flexibility you might need.

Output Function

The function generator can output five standard waveforms including sine, square, triangle, ramp, and noise. You can also select one of five predefined arbitrary waveforms or download your own custom waveforms. You can internally modulate any of the standard waveforms (including arbitrary) using frequency sweeping is available for any of the standard waveforms (except noise) and arbitrary waveforms. The default function is sine wave.

• Possible Conflict with Output Frequency: The output frequency is

automatically adjusted if you select a function whose maximum frequency is less than that of the currently active function. For example, if you output a 1 MHz sine wave and then change the function to triangle wave, the function generator will adjust the output to 100 kHz (the upper limit for triangle waves).

AM, FM, FSK, or burst modulation. Linear or logarithmic

From the front panel, “ adjusted. From the remote interface, a -221, “Settings conflict” error

is generated and the frequency is adjusted.

• Possible Conflict with Output Amplitude: The output amplitude is

automatically adjusted if you select a function whose maximum amplitude is less than that of the currently active function. This conflict may arise when the output units are Vrms or dBm due to the differences in crest factor for the output functions. For example, if you output a 5 Vrms square wave (into 50 ohms) and then change the function to sine wave, the function generator will adjust the output amplitude to 3.535 Vrms (the upper limit for sine waves in Vrms).

From the front panel, “ is adjusted. From the remote interface, a -221, “Settings conflict”

error is generated and the amplitude is adjusted.

FREQ LIMIT” is displayed and the frequency is

AMPL LIMIT” is displayed and the amplitude

Chapter 3 Features and Functions

Output Configuration

Output Function

(continued)

• The following matrix shows which output functions are allowed with

each modulation mode. Each “

X” indicates a valid combination. If you

change to a function that is not allowed with the selected modulation, the modulation mode is turned off.

AM Carrier AM Modulating Wav e FM Carrier FM Modulating Wave FSK Modulation Burst Modulation Frequency Sweep

Sine

X X X X X X X

Square

X X X X X X X

Triangle

X X X X X X X

Ramp

X X X X X X X

Noise

X X

Arb

X X X X X X X

• Front-Panel Operation: To select a function, press any key in the top

row of function keys. Press

Arb to output the arbitrary waveform

currently selected (to scroll through the waveform choices and make a selection, press

• To select

dc volts from the front panel, press Offset and hold it down

for more than 2 seconds

Arb List ).

• Remote Interface Operation:

FUNCtion:SH APe {SIN usoid|SQ Uare|T RIangl e|RAMP |NOISe|U SER|DC }

You can also use the APPLy command to select the function, frequency, amplitude, and offset with a single command.

Chapter 3 Features and Functions

Output Configuration

Output Frequency

As shown below, the output frequency range depends on the function currently selected. The default frequency is 1 kHz for all functions.

Function

Minimum Frequency

Maximum Frequency

Sine Square Triangle Ramp Built-In Arbs

1 There are five built-in arbitrary waveforms stored in non-volatile memory: sinc, negative ramp, exponential rise, exponential fall, and cardiac.

100 100 100 100 100

µHz µHz µHz µHz µHz

15 MHz 15 MHz 100 kHz 100 kHz 5 MHz

For arbitrary waveforms that you create and download to memory, the maximum frequency depends on the number of points specified in the waveform. As shown below, the maximum output frequency decreases as you specify more points in the waveform. The five built-in arbitrary waveforms can be output at a maximum of 5 MHz.

Number of Arb Points

8 to 8,192 (8k) 8,193 to 12,287 (12k) 12,288 to 16,000

Minimum Frequency

100 100 100

µHz µHz µHz

Maximum Frequency

5 MHz

2.5 MHz 200 kHz

Chapter 3 Features and Functions

Output Configuration

Output Frequency

(continued)

• Possible Conflict with Function Change: The output frequency is

From the front panel, “

FREQ LIMIT” is displayed and the frequency is

adjusted. From the remote interface, a -221, “Settings conflict” error is generated and the frequency is adjusted.

• Possible Conflict with Duty Cycle (square wave only): For output

frequencies above 5 MHz, the duty cycle is limited to values between 40% and 60% (below 5 MHz, the range is 20% to 80%). The duty cycle is automatically adjusted if you select a frequency that is not valid with the present duty cycle. For example, if you set the duty cycle to 70% and then change the frequency to 8 MHz, the function generator will automatically adjust the duty cycle to 60% (the upper limit for this frequency).

From the front panel, “

% DUTY LIMIT” is displayed and the duty cycle is

adjusted. From the remote interface, a -221, “Settings conflict” error is generated and the duty cycle is adjusted.

• Front-Panel Operation: To set the output frequency, press

Freq .

Then use the knob, arrow keys, or “Enter Number” mode to set the frequency.

• Remote Interface Operation:

FREQuency {<

frequency>|MINimum|MAXimum}

You can also use the APPLy command to select the function, frequency, amplitude, and offset with a single command.

Chapter 3 Features and Functions

Output Configuration

Output Amplitude

As shown below, the output amplitude range depends on the function currently selected and the output termination. The default amplitude is

100 mVpp (into 50 ohms) for all functions.

Function

Output Termination

Minimum Amplitude

Maximum Amplitude

Sine Square Triangle Ramp Noise Built-In Arbs

1 There are five built-in arbitrary waveforms stored in non-volatile memory: sinc, negative ramp, exponential rise, exponential fall, and cardiac.

Ω

50 50Ω 50Ω 50Ω 50Ω 50Ω

Open Circuit Open Circuit Open Circuit Open Circuit Open Circuit Open Circuit

50 mVpp 50 mVpp 50 mVpp 50 mVpp 50 mVpp 50 mVpp

100 mVpp 100 mVpp 100 mVpp 100 mVpp 100 mVpp 100 mVpp

10 Vpp 10 Vpp 10 Vpp 10 Vpp 10 Vpp 10 Vpp

20 Vpp 20 Vpp 20 Vpp 20 Vpp 20 Vpp 20 Vpp

• For arbitrary waveforms, the maximum amplitude will be limited if

the data points do not span the full range of the output

to-Analog Converter). For example, the built-in “ not use the full range of values between

±1 and therefore its

SINC” waveform does

DAC (Digital-

maximum amplitude is 6.084 Vpp (into 50 ohms).

• Possible Conflict with Function Change: The output amplitude is

From the front panel, “

AMPL LIMIT” is displayed and the amplitude is

adjusted. From the remote interface, a -221, “Settings conflict” error is generated and the amplitude is adjusted.

Chapter 3 Features and Functions

Output Configuration

Output Amplitude

(continued)

• Output Amplitude and Output Termination: The output amplitude is

automatically adjusted (and no error is generated) if you change the output termination. For example, if you set the amplitude to 10 Vpp

and then change the termination from 50 ohms to “high impedance”, the displayed amplitude will double to 20 Vpp. If you change from “high impedance” to 50 ohms, the displayed amplitude will drop in half. See “Output Termination” on page 65 for more information.

• Offset Voltage Restrictions: The output amplitude (in Vpp) and the

dc offset voltage must obey the following restrictions. If the specified amplitude is not valid, the function generator will automatically adjust it to the maximum value allowed with the present offset voltage. (Vmax is either 10 volts for a high impedance termination or 5 volts for a 50 ohm termination; Vpp is the output amplitude in volts peak-to-peak.)



offset

From the front panel, “



≤ V

MAX VALUE” is displayed and the amplitude

max

and



offset

≤ 2 x V



is adjusted. From the remote interface, a -221, “Settings conflict”

error is generated and the amplitude is adjusted.

• A momentary glitch occurs in the output waveform at certain

voltages due to output attenuator switching. This positive-going glitch occurs when the output voltage crosses the break-point voltage either from a lower voltage or a higher voltage. The voltages are shown below (for a 0 volt dc offset):

252 mVpp, 399 mVpp, 502 mVpp, 796 mVpp, 1 Vpp, 1.59 Vpp,

2.0 Vpp, 3.17 Vpp, 3.99 Vpp, 6.32 Vpp, 7.96 Vpp

• The output voltage will momentarily drop to 0 volts at certain voltages

due to output relay switching. This occurs when the output voltage crosses the break-point voltage either from a lower voltage or a higher voltage. The voltages are shown below (for a 0 volt dc offset):

317 mVpp, 632 mVpp, 1.26 Vpp, 2.52 Vpp, 5.02 Vpp

Chapter 3 Features and Functions

Output Configuration

• You can set the units for output amplitude to Vpp, Vrms, or dBm.

See “Output Units” on page 64 for more information.

• For dc volts, the output level is actually controlled by setting the

offset voltage. You can set the dc voltage to any value between into 50 ohms or

on page 62 for more information.

±10 Vdc into an open circuit. See “DC Offset Voltage”

±5 Vdc

To select

for more than 2 seconds

• Front-Panel Operation: To set the output amplitude, press

Then use the knob, arrow keys, or “Enter Number” mode to set the amplitude.

• Remote Interface Operation:

VOLTage {<

You can also use the APPLy command to select the function, frequency, amplitude, and offset with a single command.

dc volts from the front panel, press Offset and hold it down

Ampl .

amplitude>|MINimum|MAXimum}

Chapter 3 Features and Functions

Output Configuration

DC Offset Voltage

At power-on, the dc offset is set to 0 volts. You can set the offset to a positive or negative number with the restrictions shown below. If the specified offset voltage is not valid, the function generator will automatically adjust it to the maximum dc voltage allowed with the present amplitude. (Vmax is either 10 volts for a high impedance termination or 5 volts for a 50 ohm termination; Vpp is the output amplitude in volts peak-to-peak.)

 V

offset



≤ V

max

and



offset

≤ 2 x V



From the front panel, “

MAX VALUE” is displayed and the offset

is adjusted. From the remote interface, a -221, “Settings conflict” error is generated and the offset is adjusted.

• DC Offset and Output Termination: The offset voltage is automatically

adjusted (and no error is generated) if you change the output termination. For example, if you set the offset to 100 mVdc and then

change the termination from 50 ohms to “high impedance”, the displayed offset will double to 200 mVdc. If you change from “high impedance” to 50 ohms, the displayed offset will drop in half.

See “Output Termination” on page 65 for more information.

• For dc volts, the output level is actually controlled by setting the

offset voltage. You can set the dc voltage to any value between into 50 ohms or

To select

dc volts from the front panel, press Offset and hold it down

for more than 2 seconds

±10 Vdc into an open circuit.

±5 Vdc

Chapter 3 Features and Functions

Output Configuration

• For arbitrary waveforms, the Offset annunciator will turn on if the

waveform data has an inherent offset present (if the average is not equal to zero). The function generator calculates the average of the data points and compares the average to zero volts. If the average is not within two

Offset annunciator turns on.

the

DAC (Digital-to-Analog Converter) counts of zero volts,

• Front-Panel Operation: To set the dc offset, press

the knob, arrow keys, or “Enter Number” mode to set the offset.

• Remote Interface Operation:

VOLTage:OFFSet {<

You can also use the APPLy command to select the function, frequency, amplitude, and offset with a single command.

offset>|MINimum|MAXimum}

Offset . Then use

Chapter 3 Features and Functions

Output Configuration

Output Units

Applies only to output amplitude (does not affect offset). At power-on, the units for output amplitude are volts peak-to-peak.

• Output units:

Vpp, Vrms, or dBm. The default is Vpp.

• The unit setting is stored in volatile memory; the units are set to

“Vpp” when power has been off or after a remote interface reset.

• When switching from remote programming over the interface back to

front-panel (local) operation, the output units are remembered. For example, if you select “Vrms” from the remote interface, the units are shown as “Vrms” on the front-panel display.

• Front-Panel Operation: Use the “Enter Number” units keys

(the arrow keys located on the right side of the front panel) to select the output units. You can also convert from one unit to another from the front panel. For example, to convert 2 Vpp to its equivalent value in Vrms, press the following keys:

Enter Number

∨

kHz m Vrms

The converted value is 707.1 mVrms.

• Remote Interface Operation:

VOLTage:UNIT {VPP|VRMS|DBM|DEFault}

Chapter 3 Features and Functions

Output Configuration

Output Termination

Applies only to output amplitude and offset voltage. The function generator has a fixed output impedance of 50 ohms on the OUTPUT terminal. You can specify whether a 50 ohm load or an open circuit. Incorrect impedance matching between the function generator and your load will result in an amplitude or offset which does not match the specified signal level.

you are terminating the output into

• Output termination:

See the table on page 59 for a list of amplitude limits for all functions.

• The output termination setting is stored in volatile memory; 50

selected when power has been off or after a remote interface reset.

• The amplitude (or dc offset) is automatically adjusted (and no error is

generated) if you change the output termination. For example, if you set the amplitude to 10 Vpp and then change the termination from

50 ohms to “high impedance”, the displayed amplitude will double to 20 Vpp. If you change from “high impedance” to 50 ohms, the displayed amplitude will drop in half.

• If you specify a 50 ohm termination but are actually terminating into

an open circuit, the displayed output will be twice the value specified. For example, if you set the offset to 100 mVdc (and specify a 50 ohm termination) but are actually terminating the output into an open circuit, the actual displayed offset will be 200 mVdc.

• Front-Panel Operation: Choose “

front-panel menu.

1: OUT TERM (SYS MENU)

• Remote Interface Operation:

OUTPut:LOAD {50|INFinity|MINimum|MAXimum}

50Ω or High impedance. The default is 50Ω.

Ω is

50 OHM” or “HIGH Z” from the

Chapter 3 Features and Functions

Output Configuration

Duty Cycle

Applies only to square waves. Duty cycle is specified as a percentage and represents the amount of time per cycle that the square wave is high.

Duty Cycle =

(where T =

• Duty cycle: 20% to 80%, in 1% increments (frequency ≤ 5 MHz).

40% to 60%, in 1% increments (frequency > 5 MHz). The default is 50%.

frequency

)

• The duty cycle is stored in volatile memory; the duty cycle is set to

50% when power has been off or after a remote interface reset. The APPLy command automatically sets the duty cycle to 50% for square waves.

• Before attempting to set the duty cycle, you must enable the square

wave function. From the front panel, “

SQUARE ONLY” is displayed if

square wave is not currently active. From the remote interface, no error is generated, but the specified duty cycle is remembered when you change to the square wave function.

• The duty cycle setting is remembered when you change from square

wave to another function. When you return to the square wave function, the previous duty cycle is used.

Chapter 3 Features and Functions

Output Configuration

• Possible Conflict with Output Frequency: The duty cycle is auto-

matically adjusted if you select a frequency that is not valid with the present duty cycle. For example, if you set the duty cycle to 70% and then change the frequency to 8 MHz, the function generator will automatically adjust the duty cycle to 60% (the upper limit for this frequency).

From the front panel, “ adjusted. From the remote interface, a -221, “Settings conflict” error

is generated and the duty cycle is adjusted.

• Front-Panel Operation: To set the duty cycle, press

(the value appears on the display for approximately 10 seconds).

Then use the knob, arrow keys, or “Enter Number” mode to set the duty cycle.

• Remote Interface Operation:

PULSe:DCYCle {<

The APPLy command automatically sets the duty cycle to 50% for square waves.

% DUTY LIMIT” is displayed and the duty cycle is

Shift % Duty

percent>|MINimum|MAXimum}

Chapter 3 Features and Functions

Output Configuration

SYNC Signal

A sync signal output is provided on the front-panel SYNC terminal. All of the standard output functions (except dc and noise) have an associated sync signal. For certain applications where you may not want to output the sync signal, you can disable the SYNC terminal.

The SYNC terminal can be enabled/disabled from the remote interface only.

• By default, the sync signal is routed to the SYNC terminal (enabled).

• When the sync signal is disabled, the output level on the SYNC

terminal is indeterminate (it might be a

• For sine, square, triangle, and ramp waveforms, the sync signal is a

TTL “high” when the waveform’s output is positive, relative to zero

volts (or the dc offset value). The signal is a output is negative, relative to zero volts (or the dc offset value).

TTL “high” or a TTL “low”).

TTL “low” when the

• For arbitrary waveforms, a momentary

TTL “high” pulse (> 200 ns) is

output which corresponds to the first downloaded point in the waveform.

• For AM and FM, the sync signal is referenced to the modulating

signal (not the carrier). A momentary

TTL “high” pulse (> 200 ns) is

output at each zero-crossing point of the modulating signal.

• For the triggered burst mode, a

TTL “low” signal is output while the

specified number of cycles is output (for the duration of the burst). After the specified number of cycles has been output, the sync signal goes “high” until the next burst.

• For the external gated burst mode, the sync signal is a

TTL “high”

when the output is positive, relative to zero volts (or the dc offset value). The signal is a

TTL “low” when the output is negative, relative

to zero volts (or the dc offset value).

• For FSK, a momentary

TTL “high” pulse (> 200 ns) is output on the

transition to the “hop” frequency.

• For frequency sweeps, the sync signal is a

sweep (when the start frequency is output) and is a

TTL “low” at the start of the

TTL “high” at the

end of the sweep (when the stop frequency is output).

• Remote Interface Operation:

OUTPut:SYNC {OFF|ON}

Setting is stored in volatile memory.

Chapter 3 Features and Functions

Output Configuration

Instrument State Storage

You can store up to three different instrument states in non-volatile memory. This enables you to recall the entire instrument configuration with a single command from the remote interface or with just a few key presses from the front panel.

• Three memory locations (numbered 1, 2, and 3) are available to store

instrument configurations. The state storage feature “remembers” the function (including arbitrary waveforms), frequency, amplitude, dc offset, duty cycle, as well as any modulation parameters. To recall a stored state, you must use the same memory location used previously to store the state.

• You cannot recall the instrument state from a memory location that

was not previously specified as a storage location. For example, an error is generated if you attempt to recall from memory location “2” but have never stored to that location.

From the front panel, “ in the specified memory location. From the remote interface, a

+810, “State has not been stored” error is generated if nothing is stored in the specified memory location.

• Any arbitrary waveforms downloaded to “

remembered. However, if an arbitrary waveform is being output from non-volatile memory when the state is stored, the waveform data is stored. The stored waveform is output when the instrument state is recalled.

• If you delete an arbitrary waveform after storing the state, the

waveform data is lost and the function generator will not output the waveform when the state is recalled. The “ in place of the deleted waveform.

NOT STORED” is displayed if nothing is stored

VOLATILE” memory are not

SINC” waveform is output

Chapter 3 Features and Functions

Output Configuration

State Storage

(continued)

• When power is turned off, the function generator automatically stores

its state in memory location “0”. You can configure the function generator to automatically recall the power-down state when power is restored. The recall mode is disabled when the function generator is shipped from the factory.

Select the enable the power-down recall mode. Select

POWER ON LAST STATE command from the SYS MENU to

POWER ON DEFAULT to

disable the power-down recall mode. See “Power-Down Recall Mode” on page 109 for more information.

• From the remote interface, you can use memory location “0” to store

a fourth instrument configuration (you cannot store to this memory location from the front panel). However, keep in mind that memory location “0” is automatically overwritten when the power is turned off.

• Front-Panel Operation:

To store the state, press

Shift Store . Then use the knob, arrow

keys, or “Enter Number” mode to select the memory location.

To restore the state, press

Recall . Then use the knob, arrow keys,

or “Enter Number” mode to select the memory location.

• Remote Interface Operation:

*SAV {0|1|2|3}

State 0 is the instrument state at power down.

*RCL {0|1|2|3} States 1, 2, and 3 are user-defined states.

• From the remote interface, you can delete individual stored states

and clear the memory location. If nothing is stored in the specified memory location, a +810, “State has not been stored” error is generated.

MEMory:STATe:DELete {0|1|2|3}

Chapter 3 Features and Functions

Amplitude Modulation (AM)

A modulated waveform consists of a carrier waveform and a modulating waveform. In of the modulating waveform. The function generator will accept an internal modulating signal, an external modulating signal, or both.

For more information on the fundamentals of Amplitude Modulation,

refer to chapter 7, “Tutorial”.

AM, the amplitude of the carrier is varied by the amplitude

To Select AM Modulation

• The AM annunciator turns on when AM is enabled.

• Only one modulation mode can be enabled at a time. When you

enable

• Front-Panel Operation: Enable

modulation parameters. Press using the present settings for the carrier frequency, modulating frequency, output amplitude, and offset voltage.

• Remote Interface Operation: To ensure proper operation, you should

enable

AM:STATe {OFF|ON}

AM, the previous modulation mode is turned off.

AM before setting up the other

Shift AM to output an AM waveform

AM after you have set up the other modulation parameters.

Chapter 3 Features and Functions

Amplitude Modulation (AM)

Carrier Waveform Shape

• AM carrier shape: Sine, Square, Triangle, Ramp, or Arbitrary

waveform. The default is Sine.

• You cannot use the noise function or dc volts as the carrier waveform.

• Front-Panel Operation: Press any of the front-panel function keys

except

Noise . For arbitrary waveforms, the Arb key selects the

waveform that is currently downloaded.

• Remote Interface Operation:

FUNCtion:SHAPe {SINusoid|SQUare|TRIangle|RAMP|USER}

You can also use the APPLy command to select the function, frequency, amplitude, and offset with a single command.

Carrier Frequency

• Carrier frequency: 100 µHz to 15 MHz (100 kHz for triangle and ramp).

The default is 1 kHz.

• For arbitrary waveforms, the maximum carrier frequency depends on

the number of points specified in the waveform. The five built-in arbitrary waveforms can be output at a maximum of 5 MHz.

Number of Arb Points

8 to 8,192 (8k) 8,193 to 12,287 (12k) 12,288 to 16,000

Minimum Frequency

100 100 100

• Front-Panel Operation: Press the

µHz µHz µHz

Freq key to select any valid

Maximum Frequency

5 MHz

2.5 MHz 200 kHz

frequency for the selected function (the present amplitude and offset voltage are used).

• Remote Interface Operation:

FREQuency {<

frequency>|MINimum|MAXimum}

Chapter 3 Features and Functions

Amplitude Modulation (AM)

Modulating Waveform Shape

The function generator will accept an internal modulating signal, an external modulating signal, or both.

• Modulating waveform shape (internal source):

Triangle, Ramp, Noise, or Arbitrary waveform. The default is Sine.

• You can use the noise function as the modulating waveform.

However, you cannot use the noise function or dc volts as the

carrier waveform.

• Front-Panel Operation: After enabling

directly to the

1: AM SHAPE (MOD MENU)

• Remote Interface Operation:

AM:INTernal :FUNCtion {SIN usoid|SQUare |TRIangle| RAMP|NOISe|U SER}

AM SHAPE command in the menu.

AM, press Recall Menu to go

Sine, Square,

Chapter 3 Features and Functions

Amplitude Modulation (AM)

Modulating Waveform Frequency

The function generator will accept an internal modulating signal, an external modulating signal, or both.

• Modulating frequency (internal source): 10 mHz to 20 kHz.

The default is 100 Hz.

• The sync signal for

carrier). A momentary

AM is referenced to the modulating signal (not the

TTL “high” pulse (> 200 ns) is output at each

zero-crossing point of the modulating signal. The signal is output from the front-panel SYNC terminal.

• Front-Panel Operation: Press

Shift Freq to set the modulating

frequency (the value is displayed for approximately 10 seconds).

Before setting the modulating frequency from the front panel, you must have

AM is not enabled, “SELECT AM, FM” is displayed.

AM enabled. If you attempt to set the frequency when

• Remote Interface Operation:

AM:INTernal:FREQuency {<

frequency>|MINimum|MAXimum}

Modulation Depth

The modulation depth is expressed as a percentage and represents the extent of the amplitude variation. At 0% modulation, the output amplitude is half of the selected value. At 100% modulation, the output amplitude equals the selected value.

• Modulation depth: 0% to 120%. The default is 100%.

• Front-Panel Operation: Press

(the value is displayed for approximately 10 seconds).

Shift Level to set the depth in percent

Before setting the modulation depth from the front panel, you must

AM enabled. If you attempt to set the depth when AM is not

have enabled, “

SELECT AM, FM” is displayed.

• Remote Interface Operation:

AM:DEPTh {<

depth in percent>|MINimum|MAXimum}

Chapter 3 Features and Functions

Amplitude Modulation (AM)

Modulating Source

The function generator will accept an internal modulating signal, an external modulating signal, or both.

• Modulating source: Internal-External (both) or External only.

The default is Both (internal-external).

The External modulating source is always enabled.

•

• When both sources are enabled (internal-external), the function

generator adds the internal and external modulating signals

(the carrier waveform is actually modulated with two waveforms).

• When the internal source is disabled (external only), the carrier

waveform is modulated with the external waveform. The

annunciator turns on to indicate that the function generator is

expecting a modulating signal on the rear-panel AM Modulation

terminal.

• You apply the external modulating waveform to the AM Modulation

terminal. The modulation depth is controlled by the signal level

present (5 volts

peak corresponds to 100% modulation).

Ext

• Front-Panel Operation:

2: AM SOURCE (MOD MENU)

• Remote Interface Operation:

AM:SOURce {BOTH|EXTernal}

5 V

0 V

-5 V

Chapter 3 Features and Functions

Frequency Modulation (FM)

A modulated waveform consists of a carrier waveform and a modulating waveform. In of the modulating waveform. The function generator will accept only an internal

For more information on the fundamentals of Frequency Modulation,

refer to chapter 7, “Tutorial”.

To Select FM Modulation

• The FM annunciator turns on when FM is enabled.

• Only one modulation mode can be enabled at a time. When you

enable

FM, the frequency of the carrier is varied by the amplitude

FM modulating signal (no external source is available).

FM, the previous modulation mode is turned off.

• Front-Panel Operation: Enable

modulation parameters. Press

FM before setting up the other

Shift FM to output an FM waveform

using the present settings for the carrier frequency, modulating frequency, output amplitude, and offset voltage.

• Remote Interface Operation: To ensure proper operation, you should

enable

FM after you have set up the other modulation parameters.

FM:STATe {OFF|ON}

Chapter 3 Features and Functions

Frequency Modulation (FM)