Oscilloscope calibration error

Discussion in 'General Electronics Chat' started by nxp, Mar 2, 2011.

  1. nxp

    Thread Starter New Member

    Jun 6, 2010

    I just bought a oscilloscope Fluke PM3380A.

    I receive the message that i need to do a autocalibration by pressing the key "cal" 2 sec. What i tried... After 3 minutes i receive the message "calibration incomplete" please retry... It's never working...

    In the maintenance menu i can see "calibration error 191". Wjat does it mean?

    Is it normal or is it important? What can i do?

    Thank you!

  2. SgtWookie


    Jul 17, 2007
    I don't know a thing about that model.
    Someone claims they posted a scan of a service repair manual that covers that model here:
    I guess you have to be a member to even see that an attachment exists.
    But, I'll bet that the service manual would at least say what the error number means.
  3. someonesdad

    Senior Member

    Jul 7, 2009
    In lieu of getting the manual, you could do some simple checks to see if the scope appears calibrated. Measure a battery with a digital multimeter you trust, then check the gain of the vertical amplifier(s). Use some voltage dividers to check the higher gain settings.

    For timing, you can check the frequency of the AC line -- use a transformer to step it down to, say, 6.3 VAC. The line frequency accuracy should be around 0.1% or better, so it should be sufficient to calibrate a slow sweep. You could also make an oscillator with a crystal or ceramic resonator.