AV-modded Famicom shuts off randomly?

Discussion in 'Modding and Hacking - Consoles and Electronics' started by StriderSubzero, Apr 10, 2018.

  1. StriderSubzero

    StriderSubzero Active Member

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    Hi all,

    I modded a Famicom with AV output, which seems to work fine. I haven't done a great deal of testing, but occasionally the console will do a hard shut-off a few minutes after booting it up. It's possible it did this before the mod, but I didn't use it much so it's hard to say.

    Does anyone know why this might be happening?
     
  2. MonkeyBoyJoey

    MonkeyBoyJoey 70's Robot Anime GEPPY-X (PS1) Fanatic

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    What power supply are you using? How many volts and amps?
     
  3. StriderSubzero

    StriderSubzero Active Member

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    I'm using the US Genesis model 1 adapter, it's 9V - 1.2 Amp
     
  4. AtomizerZero

    AtomizerZero Intrepid Member

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    Does the power actually cut out? or does the game just stop working?

    If you have a multimeter, test the voltage regulator. Also check all capacitors.

    Also check to make sure the power socket isnt dirty or loose and that the power adapter isn't faulty or wire broken.
     
  5. StriderSubzero

    StriderSubzero Active Member

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    The power actually cuts off. The screen flashes and then it goes black, almost like a short-circuit or something.

    One thing that could be worth saying is one of the wires going to the power switch was broken so I rewired it, but it wouldn't turn on at all before I did that, so I don't think it's related.

    The AC adapter is fine; I use it on the Genesis and Sega CD without issue.

    I'm honestly not entirely sure where the voltage regulator is, but I do have a multimeter.
     
  6. MonkeyBoyJoey

    MonkeyBoyJoey 70's Robot Anime GEPPY-X (PS1) Fanatic

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    Glad to hear that the PSU is confirmed working so we can rule it out.

    It's a tall black flat box with 3 prongs that has 7805 written on it. You can find it near the power jack on the Power/AV board iirc. Should be screwed into the heat sink.
     
  7. MottZilla

    MottZilla Champion of the Forum

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    You could try running it with fans to keep it cool. Maybe remove the top of the case and get a decent fan to cool the whole thing and see if it does the same thing. It could shut off if the regulator gets too hot I think. Or maybe the regulator is going bad and needs to be replaced.
     
  8. AtomizerZero

    AtomizerZero Intrepid Member

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    @StriderSubzero Replace the 7805. I will almost guarantee that it'll fix it.
     

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