AnsweredAssumed Answered

HP 54502A scope with defective input channel: help needed

Question asked by silbermann on Feb 1, 2008
Latest reply on Feb 15, 2008 by silbermann
hi experts!

i just acquired a HP 54502A scope with one input attenuator missing. When the remaining attenuator is in Ch1 the scope seems to work, however i am not sure whether the ac-square wave signal looks a bit too noisy and the following self-tests fail:

  • 'Analog Trigger': (error code 0000 0000 0000 0001)

  • 'D/A Converter': (error code 0000 0000 0000 0001)

  • 'A/D Converter':  (error code 0000 0000 0011 1101)
i have no idea what these codes mean, but i hope they are merely due to the missing attenuator assembly in Ch2.
Now, if i swap the attenuator assembly to Ch2 the same self-tests do  fail. when i  connect the ac-calibration signal to Ch2 i can see the signal but when i decrease the vertical sensitivity starting from 5V/div with the FINE key selected, the displayed amplitude of the signal does not change continuously but only jumps up exactly when i can hear the attenuator's solenoids switching (this takes place between 1.20 and 1.15V/div, 235 and 230mV/div and 47 and 46mV/div).

I am not exactly an expert in electronics so any help with this problem would be greatly appreciated!

Thanks in advance