Cheap plug packs

Discussion in 'Power Supplies' started by David_AVD, Jan 13, 2012.

  1. David_AVD

    David_AVD Good news, everyone!

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    This may explain why people using cheap plug packs for transmitters, etc have so much hum and rubbish in the audio!

    Crappy PSU analysis
     
  2. lithgowlights

    lithgowlights Senior Elf

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    That is scary, but not that suprising
     
  3. AAH

    AAH I love blinky lights :) Community Project Designer

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    It even had the all important CE (China Export) label on it. I was thinking that it was a linear supply originally until he said it was a 1 transistor switchmode.
     
  4. AussiePhil

    AussiePhil Dedicated Elf Administrator

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    Nice Work David

    Also nicely illustrates voltage drop on thin cables.

    Also not particularly unexpected though but still a bit scary.

    Phil
     
  5. XDU

    XDU Full Time Elf

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    it would have been interesting to see the output noise
     
  6. OP
    OP
    David_AVD

    David_AVD Good news, everyone!

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    Maybe not unexpected to us propeller heads, but the average layman would never suspect it.

    I just thought it worth linking to so that people think a little more about what they're buying.
     
  7. Benschristmaslights

    Benschristmaslights Dedicated Elf Global Moderator Generous Elf

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    interesting to see David i had this problem myself with a power pack. i plugged the transmitter into a usb port for power instead. thanks to Ryans advice and now i do not have a hum or a buzz in the audio. very interesting to watch.
     
  8. Bird

    Bird Proud LOR user

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    That would be me on the electronics :)
    Thanks for the heads up David, nicely done.
     
  9. fasteddy

    fasteddy I have C.L.A.P Global Moderator Generous Elf

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    Great stuff David, that will help people understand that power supplies are not just power supplies, there is a difference in quality
     

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