AnsweredAssumed Answered

HP 8591A "cal sig not found"

Question asked by rodorr on Oct 24, 2011
Latest reply on Oct 24, 2011 by tabbott
I have an HP 8591A Spectrum Analyzer that I just purchased used. It will not make it through
frequency calibration or amplitude calibration. All I get is the error message "cal sig not
found". I have run the calibration using both the -37 and -2001 passcodes with no luck.
The 300mhz calibration signal is present but very low amplitude. When I adjust  the
amplitude I can hear the A3 programable attenuator relays functioning and the calibration
signal that is present does vary proportionaly with the 0 to 60db attenuation so I'm pretty
sure the A3 module relays are functioning properly. I'm leaning towards the possibilty that it was
hit with a fair amount of rf and has possibly taken out something besides the relays in the A3
module. My next check will be to bypass the A3 module and see what I get. I'm just looking for
some input as to what anyone on the forum thinks could be the problem. Any suggestions will be