AnsweredAssumed Answered

Reference Level on E4407B

Question asked by sgpars on Mar 24, 2014
Latest reply on Apr 21, 2014 by tabbott

I am trying to measure a signal with multiple harmonics and have a question about setting the reference level/attenuation.  I am setting the frequency span so that I only see one harmonic at a time and want to know if you set the reference level/attenuation based on the power of that particular harmonic or do you need to set it to the highest power level for the entire signal, even though only one of the harmonics is within the frequency span?

In other words, I have a signal that contains:
1 GHz @ 0 dBm
2 GHz @ -10 dBm
3 GHz @ -20 dBm

I set the frequency span to only show one of these signals at a time.  Should I set the reference level to 0 dBm or is it ok to set it at -20 dBm when measuring the 3rd harmonic?

I ask because when I change the attenuation level to anything other than 5 dB I get very different power measurements for the 3rd harmonic.

Edited by: sgpars on Mar 24, 2014 3:54 PM