SNES screen interference

Discussion in 'Other Consoles & Oldies' started by Ashramkun, May 5, 2017.

  1. Ashramkun
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    Ashramkun Member

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    Sep 30, 2013
    Brazil
    Hello

    My SNES has a strange interference, and I would like to know if someone has any ideas what is the problem.



    Can you notice the strange waves in the screen?
    I am using:
    - genuine AC adapter
    - genuine composite cable
    - tested with a SCART + Framemeinster too

    I read something about change capacitors, and change the AC adapter, but I would like your opinion before try.
     
  2. SmileCitrus

    SmileCitrus GBAtemp Regular

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    Mar 29, 2009
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    It's a little bit hard to tell for sure from the video, but this looks like the 7805 voltage regulator is bad. Those waves could also be caused by cheap aftermarket AC adapters, but since you're using a genuine one it's probably fine. It's easy and cheap to replace the voltage regulator as long if you can solder. You can get replacements on Console5 or eBay, or any place that sells electronic components like Digi-Key or Mouser.
     
  3. Ashramkun
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    Ashramkun Member

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    Sep 30, 2013
    Brazil
    Hello
    Well, I used a multimeter at 7805, and got:
    -left side: 10.63V
    -right side: 4.85V

    Looks like its normal, right? 4.85v isn't 5v, but I don't know if 0.15 will make that difference.

    Now, I have the option to change the capacitors and the crystal oscillator. Thanks anyway for your ideia.
     
  4. SmileCitrus

    SmileCitrus GBAtemp Regular

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    It does look normal, but I've had some systems where the output measured 4.99v but there were still wavy lines in the video. Replacing it solved the issue for me with those consoles, so it could still be the 7805 even if the output seems normal. I still think it's worth a shot, since the part is cheap.
     
    Ashramkun likes this.
  5. Ashramkun
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    Ashramkun Member

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    Hello SmileCitrus. Just to let you know, I finally changed the 7805 as you suggested, and its working now! Thanks alot for your help!
     
  6. SmileCitrus

    SmileCitrus GBAtemp Regular

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    Nice. Glad to hear it did the trick :)