Frequency Modulation Incidental AM

(E8663D Option HE3 and E8257N Only)

Frequency Modulation Incidental AM is a measure of the amplitude variation of a frequency modulated signal.

The spectrum analyzer is placed in zero span, and a time-domain measurement is made of the signal generator's input signal, which will be a frequency modulated signal of nominally constant amplitude. The resolution bandwidth of the spectrum analyzer will be wide enough compared to the frequency deviation (8 MHz vs. 50 kHz) such that the frequency response of the spectrum analyzer is assumed to be constant. The minimum and maximum amplitude of the waveform is measured and the incidental AM is calculated from these measurements.

Required Test Equipment

Test Equipment

Recommended Models

Alternative Models

Spectrum Analyzer

N9030B Opt 5xx1, MPB2

N9030A Opt 5xx1, MPB2

E444xA3 Opt 1232
  1. Select any option of PXA spectrum analyzer (503, 508, 513, 526, 543, 544, 550) that has a maximum frequency greater than or equal to the maximum frequency of the unit under test. An N9030A/B Option 550 is required for units with Option 567. The N9030A/B Option 550 frequency range is adequate for all PSG-D frequency configurations.
  2. Microwave Preselector Bypass Option MPB (PXA) or 123 (PSA) is used by not required by this test.
  3. Select any model of PSA spectrum analyzer (E4440A, E4443A,E4445A, E4446A, E4447A, E4448A) that has a maximum frequency greater than or equal to the maximum frequency of the unit under test. An E4448A is required for units with Option 567. The E4448A frequency range is adequate for all PSG-D frequency configurations.

 

Connections and Setup Procedures

  • All test equipment requires a 30 minute warmup period to ensure accurate performance.

  • In the following test setup, cables are designated as solid lines and direct connections are designated as dashed lines.

  • This performance test has a smart connection feature.

  1. Connect all test equipment as shown.

  2. Connect GPIB cables to all GPIB-controlled test equipment.

  3. While performing this performance test, follow all instructions on the controller display.

 

Setup for Frequency Modulation Incidental AM

 

In Case of Difficulty

If this performance test fails, perform the following steps in order:

  1. Check the equipment setup (see above). If the setup is incorrect, make the necessary corrections and rerun the Performance Test.

  2. If this test fails with the equipment set up properly, refer to the troubleshooting section of the signal generator's service guide. If you do not have a printed copy of the service guide (Option OBW), one is available either on the CD-ROM that came with your signal generator shipment or on the Keysight Website.

  3. If you cannot correct the problem using the troubleshooting procedures in the Service Guide, obtain service from Keysight Technologies. Refer to Contacting Keysight Technologies.