External Pulse Modulation On/Off Ratio
(E8257D/E8267D Option UNU with serial prefix < 4928, UNW, UNS, or HNS,
  E8663D Option UNW and E8257N Only)

A DC voltage is used to switch the DUT pulse modulation on and off. A spectrum analyzer is used to measure the power of the fundamental (CW) frequency of the DUT with the pulse On and Off. The difference in these power levels is the Pulse On/Off ratio, in dB

Required Test Equipment

Test Equipment

Recommended Models

Alternative Models

Spectrum Analyzer

N9030B Opt 5xx1

N9030A Opt 5xx1

E444xA2

Function Generator

33622A

33611A
33612A
33621A
33250A
33120A Opt 001
  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. 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.

  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 Pulse Modulation On/Off Ratio

 

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 a 856xE/EC series spectrum analyzer is being used and the test locks up, please check and ensure that the 856xE/EC's external reference is connected. The spectrum analyzer will lock up and not take a sweep when external reference is selected and there isn't one connected to it.

  3. If this test fails with the equipment setup 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.

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