Does anyone has information about 1mW/50MHz Ref source output stability. I'm interested about output power variation not the spesification limits.
I have tried to measure 1mW output source with 432A/478A-H76 thermisor mount, but i have found that Ref putput power variying from 0.995 to 1.003mW (mount
is all the time at the same position without re-connecting). Is it normal behaving? From 432A meter i have taken Vcomp and Vref voltages
to HP 3458A DVM and calculated power output from those voltage values as E4418B service guide says.
Should i take account some issues during that measurement process?
I have tried to measure 1mW output source with 432A/478A-H76 thermisor mount, but i have found that Ref putput power variying from 0.995 to 1.003mW (mount
is all the time at the same position without re-connecting). Is it normal behaving? From 432A meter i have taken Vcomp and Vref voltages
to HP 3458A DVM and calculated power output from those voltage values as E4418B service guide says.
Should i take account some issues during that measurement process?
You will get some variation in signal levels over time due to temperature and time instabilities in both the E4418B's 1 mW reference signal, the thermistor mount and its cable, and the 432A/3458A you are using. All of these variables should be included in the uncertainty analysis you are using when making this calibration.
But you are fine. You are within spec.