Set the modulation depth to 80% | Agilent Technologies 33120A

Enter

Shift

Freq

Shift

Level

Chapter 3 Front-Panel Menu Operation

To output a modulated waveform

4Move down a level 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 AM annunciator flashes, indicating that the displayed parameter is for AM.

SINE

5Save the change and turn off the menu.

The modulating waveform is now a sine waveform.

ENTERED

6Set the modulating frequency to 200 Hz.

Notice that the AM annunciator flashes, indicating that the displayed frequency is the modulating frequency. Also notice that the modulating frequency is displayed with fewer digits than the carrier frequency.

MOD 200.0 Hz

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

7Set the modulation depth to 80%.

Notice that the AM annunciator flashes, indicating that the displayed percentage is the AM depth (also called percent modulation).

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 AM waveform with the specified modulation parameters.

46

Image 48

Agilent Technologies 33120A manual Move down a level verify that Sine is selected, Set the modulating frequency to 200 Hz

Contents

Service Guide Agilent 33120A MHz Function Arbitrary Waveform GeneratorPage Convenient bench-top features Flexible system features Front Panel at a Glance Front-Panel Number Entry Front-Panel Menu at a Glance MODulation Menu Display Annunciators Trig Rear Panel at a Glance Use the front-panel Input / Output Menu to This Book Page Contents Contents Service SchematicsReplaceable Parts Contents Specifications Waveforms Modulation Characteristics General Specifications Product Dimensions Page Quick Start Quick Start One User’s Guide 〈 This Service Guide Connect the power cord and turn on the function generatorTo prepare the function generator for use Check the list of supplied items Verify that there is ac power to the function generator Verify the power-line voltage settingVerify that the power-line fuse is good If the function generator does not turn on Remove the power cord . Remove To adjust the carrying handle To cancel the number mode, press Shift Cancel To set the output frequencyEnter the magnitude of the desired frequency Set the units to the desired value To set the output amplitude Enter the magnitude of the desired amplitude How to change the offset to -1.5 mVdc Enable the offset modify modeTo set a dc offset voltage Enter the magnitude of the desired offset To set the duty cycle Select the square wave functionEnter the desired duty cycle Output the waveform with the displayed duty cycle To output a stored arbitrary waveform Display the list of arbitrary waveformsMove across to the Exprise choice Select and output the displayed arbitrary waveform To output a dc voltage Enter the magnitude of the desired voltage Set up the function generator to the desired configuration Turn on the state storage modeTo store the instrument state Save the instrument state Restore the instrument state Recall the stored instrument state To rack mount the function generator Quick Start Front-Panel Menu Operation Front-Panel Menu Operation Front-panel menu reference MODulation Menu Front-panel menu reference SYStem Menu Front-panel menu tutorial Messages Displayed During Menu Use Move across to the Power on command on this level Turn on the menuMove across to the SYS Menu choice on this level Cycle the power to restore the default values Move down a level to the Parameter choicesSave the change and turn off the menu Select amplitude adjustment Increment the first digit until 300.0 mVPP is displayed Move down a level to the OUT Term command To select the output terminationMove down a level and then across to the High Z choice To output a modulated waveform Select AMUse the menu to select the shape of the modulating waveform Move down a level verify that Sine is selected Set the modulating frequency to 200 HzSet the modulation depth to 80% Move down a level to the Secured command To unsecure the function generator for calibrationMove across to the CAL Menu choice on this level Move down to the parameters level Calibration Procedures Calibration Procedures Agilent Calibration Services Calibration IntervalTime Required for Calibration Automating Calibration Procedures Recommended Test Equipment Test Considerations Performance Verification Tests Self-Test Quick Performance Check Frequency Verification Function Gain and Linearity Verification DC Function Offset Verification AC Amplitude Verification AC Amplitude Verification Vrms 0.00035 Vrms Amplitude Flatness Verification 15.00 MHz AM Modulation Depth Verification Vrms 0.0061 Vrms Optional Performance Verification Tests Square Wave Duty Cycle Verification Distortion Verification Calibration Security Code Characters To Unsecure the Function Generator Without the Security Code Calibration Count Calibration Message General Calibration/Adjustment Procedure Move down a level to the Unsecured commandBegin the Frequency and Burst Rate adjustment procedure Move across to the Calibrate choice Perform the next adjustment procedure Calculate and save the new value Frequency and Burst Rate Adjustment Aborting a Calibration in Progress Function Gain and Linearity Adjustment AC Amplitude Adjustment High-Z AC Amplitude Adjustment High-Z Modulation Adjustment Frequency Amplitude AC Amplitude Adjustment 50W AC Amplitude Adjustment 50W Adjustment for KHz DC Output Adjustment Setup Duty Cycle Adjustment AC Amplitude Flatness Adjustment AC Amplitude Flatness Adjustment Exiting Output Amplifier Adjustment Optional Error Messages System Error MessagesSelf-Test Error Messages Calibration Error Messages Theory of Operation Self-test procedures are described in chapter Theory of Operation Block Diagram Overview This discussion pertains to the block diagram shown on Block 8 on block diagram page 129 Schematic on Output Attenuator Block 7 on block diagram page 129 Schematic on Output Amplifier 740 R710 R717 740 R710 R711 R715 R716 R719 R720 AM Modulation Block 6 on block diagram page 129 Schematic on Block 6 on block diagram page 129, schematic onPre-attenuator Square Wave and Sync Square Wave and Sync Block 5 on block diagram page 129 Schematic on Filters Block 4 on block diagram page 129 Schematic on Waveform DAC/Amplitude Leveling/Waveform RAM Waveform DAC/Amplitude Leveling/Waveform RAM Block 2 on block diagram page 129 Schematic on Direct Digital Synthesis DDS Asic Block 3 on block diagram page 129 Schematic on System DACs Block 1 on block diagram page 129 Schematic on Floating Logic Power Supplies Block 9 on block diagram page 129 Schematic onBlock 10 on block diagram page 129 Schematic on Earth-Referenced Logic Power Supplies Block 11 on block diagram page 129 Schematic on Display and KeyboardSee Service Service Operating Checklist Is the function generator inoperative?See To prepare the function generator for use on Does the function generator fail self-test? Types of Service Available Call 1-877-447-7278 and ask for Agilent Express Cleaning Repackaging for ShipmentAgilent suggests that you always insure shipments Electrostatic Discharge ESD Precautions Surface Mount Repair To Replace the Power-Line Fuse To Replace the Output Protection Fuse F801 Troubleshooting Hints Unit Reports ErrorUnit is Inoperative Unit Fails Self-Test Power Supply Problems Self-Test Procedures Power-On Self-Test 625 112 Replaceable Parts Replaceable Parts Main PC Assembly 116 117 118 119 120 121 122 123 Display and Keyboard PC Assembly 33120A Mainframe Manufacturer’s List Schematics8 Schematics Block Diagram Pull Off Handle Loosen Captive Sheet 1 132 Sheet 3 Sheet 4 Waveform DAC Schematic 134 Sheet 5 136 Sheet 7 Sheet 8 Output Attenuator Schematic 138 Sheet 9 of 10 Earth Reference Logic Schematic Sheet 10 Power Supplies Schematic 140 Sheet 1 of 1 Display and Keyboard Schematic TOP Side 33120-66521 REV a TOP Side 33120-66502 REV C Manual Part Number