Issues with my scope???

Discussion in 'General Electronics Chat' started by electronewb, May 2, 2012.

  1. electronewb

    Thread Starter Member

    Apr 24, 2012
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    Here's the wave I'm getting on my scope It's a 10VAC power supply The tips and bottoms are chopped like it's compressed or something. I know that supply is smooth as I probed it on my friend's scope. What could it be?[​IMG]
     
  2. electronewb

    Thread Starter Member

    Apr 24, 2012
    260
    3
    I should add I get perfect waves from my signal generator
     
  3. praondevou

    AAC Fanatic!

    Jul 9, 2011
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    The mains voltage is not a perfect sinewave depending on other loads around you. Your power adapter can also add distortion to the signal.

    Nothing abnormal.
     
  4. electronewb

    Thread Starter Member

    Apr 24, 2012
    260
    3
    I tried 4 different outlets and exact same wave!!! Would a power conditioner help? I have a Furman laying around that I have no use for maybe I should use it and see if there's a difference!!!! Maybe the AC is dirty in my basement as well
     
  5. praondevou

    AAC Fanatic!

    Jul 9, 2011
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    Most likely the AC is the same everywhere in your home.

    If you want a sinewave with a lower THD you could just filter it with passive components. This, of course, will change it's phase and affect voltage and available current.

    Do you want to use it as a reference? Then why not use the function generator?
     
  6. electronewb

    Thread Starter Member

    Apr 24, 2012
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    I guess I won't have a choice to use the signal generator!!! Thanks for the help praondevou
     
  7. crutschow

    Expert

    Mar 14, 2008
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    Can't really tell what is looks like from your blurry post. Post a clearer one.
     
  8. #12

    Expert

    Nov 30, 2010
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    One of your problems is that you haven't figured out that the "earth" connection is the same in all your outlets. They are all intentionally wired to the same place. I fear that telling you to cut the third prong off the cord of the signal generator or scope is a safety hazard but that's one way to do this. Using a small 120v:120v trasformer is another way.

    The strange part of your waveform is not an oscilloscope problem. The 'scope is correctly displaying the voltage that is being provided to you by the power company. It gets distorted because motors are connected at other peoples' houses.
     
  9. electronewb

    Thread Starter Member

    Apr 24, 2012
    260
    3
    I have a ground lift I will give that a try!!!
     
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