HP 8560A Noise Floor

[John]

I just bought an HP 8560A SA. I'd like to check the noise floor. Does
anyone know what test conditions should be used to test noise floor ? ( I
understand noise floor should be between -103 dBm and - 130 dBm)

Also, I am looking for a 8560A Service Manual. Does anyone happen to have
one maybe on CD ?

Thank you,
John Mortlock

 

[Bob M.]

On my 8591E I believe the noise floor is measured at just about the
narrowest bandwidths you have available, i.e. 1 Hz if you have it, with the
input terminated with a shielded 50 ohm load. You may need to turn on video
averaging if you have it, and go out and actually grow some coffee to brew
while you wait for it to do enough scans to get the noise level really down
there.

I gave up and just took HP's word for it.

I intend to send mine in for calibration some day and hope that it'll come
back with some indication of the actual noise floor in the test results.

Bob M.
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