Agilent 33120A User's Guide

Chapter 3 Features and FunctionsAmplitude Modulation (AM)Modulating Waveform FrequencyThe function generator will accept an internal modulating signal,an external modulating signal, or both.œ Modulating frequency (internal source): 10 mHz to 20 kHz.The default is 100 Hz.œ The sync signal for AM is referenced to the modulating signal (not thecarrier). A momentary TTL “high” pulse (> 200 ns) is output at eachzero-crossing point of the modulating signal. The signal is outputfrom the front-panel SYNC terminal.œ Front-Panel Operation: Press Shift Freq to set the modulatingfrequency (the value is displayed for approximately 10 seconds).Before setting the modulating frequency from the front panel,you must have AM enabled. If you attempt to set the frequency whenAM is not enabled, “SELECT AM, FM” is displayed.œ Remote Interface Operation:AM:INTernal:FREQuency {|MINimum|MAXimum}Modulation DepthThe modulation depth is expressed as a percentage and represents theextent of the amplitude variation. At 0% modulation, the output amplitudeis half of the selected value. At 100% modulation, the output amplitudeequals the selected value.œ Modulation depth: 0% to 120%. The default is 100%.œ Front-Panel Operation: Press Shift Level to set the depth in percent(the value is displayed for approximately 10 seconds).Before setting the modulation depth from the front panel, you musthave AM enabled. If you attempt to set the depth when AM is notenabled, “SELECT AM, FM” is displayed.œ Remote Interface Operation:AM:DEPTh {|MINimum|MAXimum}74