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Thread: scanner noise

  1. #1
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    Default scanner noise

    Ok i´m a newbie
    I´ve just powered up my first set of galvos
    These are a pair of cambridge 6810 galvos with 650 amps.
    My problem is that they produce a sizzeling hf noise
    is this normal?

  2. #2
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    I don't own any cambridge galvos myself, but if they're like most other galvos I don't think they should make any noise in the absence of a signal. If they make some noise while displaying frames, it's fine.. but they should be silent and not move at all if there is no signal

  3. #3
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    Quote Originally Posted by ElektroFreak View Post
    I don't own any cambridge galvos myself, but if they're like most other galvos I don't think they should make any noise in the absence of a signal. If they make some noise while displaying frames, it's fine.. but they should be silent and not move at all if there is no signal

    Many galvos sing at neutral. my EyeMagics radiate what sounds like a small whine. My chinese galvos have a white noise quality to their sound.

    You may be just fine, or your really mistuned. Look at your PSU rails with a scope, if they are solid DC, I'd think your ready to start with a small laser signal and see if things look ok.

    If however a switching power supply is starting to go bad, sometimes the load "sings".So check the psus and then try a very small laser signal..

    Is this true with grounded inputs or are the galvos inputs floating? Are you near a strong RF transmitter?
    Steve
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  4. #4
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    I also noticed this noise when i mixed up Y with X, seems one of the galvo's is tuned out of it's range.

    Ferry

  5. #5
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    Default galvos

    each galvo is tune to each amp one thing you dont want to do is mix them up
    you can soon kill a galvo doing that, i have been there dont that, and cost me a lot of $$$
    i take it they are ok when connected correctly ??

  6. #6
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    Quote Originally Posted by badger1666 View Post
    each galvo is tune to each amp one thing you dont want to do is mix them up
    you can soon kill a galvo doing that, i have been there dont that, and cost me a lot of $$$
    i take it they are ok when connected correctly ??
    i am glad here is no problem....
    As soon i heard the high pitched sound, i switched off everything

    Ferry

  7. #7
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    Quote Originally Posted by satje View Post
    i am glad here is no problem....
    As soon i heard the high pitched sound, i switched off everything

    Ferry
    ok sounds like it went into self oscilation but is it ok when connected correctly ??

  8. #8
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    i use a rock solid linear psu at 2x7A and +/-27v
    the amps have the higher torque mod (modded for 24-27v)
    the only psu problem i notice is the "onboard-regulators" for the +15v rail gets realy hot

    the input is grounded

    i noticed that when i lower the gain with the mirror allign jumper, the sound disapears

    i can´t notice any movement just that singing

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