Measuring DC Level with the Generator On in APx500

Created on 2011-02-08 19:23:00

Question: I would like to measure the DC voltage on the remote control output of an amplifier while driving the amplifier input with a sine wave from the APx generator. Is there a way to keep the generator output on while observing DC level?

Answer: In APx500 v2.8 and later, the DC Level measurementallows you to do this. In all versions, you can also use use the Measurement Recorder, Multitone Analyzer, or Signal Analyzer measurements. Measurement Recorder and Multitone Analyzer both have a DC Level view. To use Signal Analyzer involves some additional steps to view the DC bin (0 Hz).

  1. Add the Signal Analyzer measurement to your signal path.
  2. Make sure that DC Coupling is selected in the Signal Path Setup Input Configuration.
  3. Select the FFT Spectrum view.
  4. Click the Edit Graph Properties icon or select Graph Properties from the right-click menu.
  5. Click the X Axis tab, un-check Logarithmic, and enter 0 Hz into the Left range field. Then close the Graph Properties window.
  6. Click the Start button to make the measurement.
  7. The DC voltage magnitude will be the value of the 0 Hz bin This measurement, unlike the others mentioned, does not indicate polarity.