Oscilloscope Question

Discussion in 'General Electronics Chat' started by vladtess, Dec 6, 2011.

  1. vladtess

    Thread Starter Member

    Jan 5, 2011
    Hi there. So today I got my cheap Rigol oscilloscope and decided to do some testing.

    Now.. I'll get to the problem: I connected both probes with same setting (DC coupling, 1x, etc) to the machine and to the same wires that generate the waveform (meaning probes are connected to together and attached to the generator), and pressed auto button. Two waveforms came up at two different voltages. Is that what I'm supposed to be gettin?!!

    Pic attached. thanks!!!
  2. Adjuster

    Late Member

    Dec 26, 2010
    Since this appears to be a 10:1 discrepancy, my first guess would be a probe setting error. Both the probe and the oscilloscope probe setting (if provided) have to agree.

    If the scope does have a probe attenuation setting, this may be manual, or automatic - the latter perhaps less probable on an inexpensive machine with simpler probes.
  3. bountyhunter

    Well-Known Member

    Sep 7, 2009
    Sometimes a 10X probe fails to "tell" the scope it's set at 10X. See it all the time. Probe may be flaky or the scope may simply not be designed to work with that brand of probe.
  4. vladtess

    Thread Starter Member

    Jan 5, 2011
    Thanks you guys, but it wasn't the problem. It seems that one of the probes is bad, since when I connected 30 watt supply to the probe it got warm drawing up 10 watts of power. So just gotta get a good pair of probes. Thanks much ya'll!