Well, tonight I decided to remove some power supplies in my setup in order to reduce cable clutter. I decided to have my Twin Famicom use my Atari 5200's power supply (mainly because it puts out better amperage; the Twin Fami needs 1.25A compared to the 650mA I had going in it), since my 5200's power supply is one of those multiplug adapters. While double checking the polarity on the Twin Fami, I must've accidentally removed the plug... and put it in the wrong polarity. Big mistake. So, I plugged it in the Twin Fami and sure enough, I heard a loud bang come from inside the system and smoke poured out of the air vents.
I just got through taking it apart not too long ago, and it turns out that pop was one of the capacitors on the power/AV board, which burst. Hopefully once it's replaced, it'll be working again. Is there a possibility that something else could've been damaged?
And for reference, the capacitor in question is the large one rated at 2200uF, the one nearest the power jack.
Hopefully it's the only thing that blew, and maybe the 7805 power regulator too. Get one of those too, just in case, they don't cost more than a dollar and you'll save a trip to the electronics store if you find it blown.
I find it amazing that it didn't have any reverse polarity protection. I disassembled an AV Famicom (to be specific, satoshi_matrix's AV Famicom) and found a diode in line with the power supply, so that in a reverse polarity situation it won't conduct, protecting the system. It may be a good idea to install a 1N4002 rectifier diode in line with the positive coming from the adapter, to prevent this from happening again.
Quote from: 133MHz on December 28, 2007, 12:19:01 am
Hopefully it's the only thing that blew, and maybe the 7805 power regulator too. Get one of those too, just in case, they don't cost more than a dollar and you'll save a trip to the electronics store if you find it blown.
I find it amazing that it didn't have any reverse polarity protection. I disassembled an AV Famicom (to be specific, satoshi_matrix's AV Famicom) and found a diode in line with the power supply, so that in a reverse polarity situation it won't conduct, protecting the system. It may be a good idea to install a 1N4002 rectifier diode in line with the positive coming from the adapter, to prevent this from happening again.
Well, it's a good thing I have a new 7805 laying around; hopefully I don't have to wind up replacing it. And yes, I'll definitely consider soldering in a rectifier diode,
especially after all this.
Quote from: 133MHz on December 28, 2007, 12:19:01 am
It may be a good idea to install a 1N4002 rectifier diode in line with the positive coming from the adapter, to prevent this from happening again.
Quote from: 2A03 on December 28, 2007, 12:41:07 am
I'll definitely consider soldering in a rectifier diode, especially after all this.
Wise decision, and a very good warning to all Twin Famicom owners ;).
Quote from: 133MHz on December 28, 2007, 12:45:53 am
Wise decision, and a very good warning to all Twin Famicom owners ;).
Especially if they plan to use any multiplug adapter.
I just about lost it when I saw the smoke coming out of my Twin Fami...
and thats when I just use the ac adapter that came with it........
Quote from: kite200 on December 28, 2007, 12:42:37 pm
and thats when I just use the ac adapter that came with it........
The power supply that came with mine wasn't even the right one; it was a PC Engine power supply with a different tip spliced on and the polarity reversed.
Quote from: 133MHz on December 28, 2007, 12:45:53 am
Quote from: 133MHz on December 28, 2007, 12:19:01 am
It may be a good idea to install a 1N4002 rectifier diode in line with the positive coming from the adapter, to prevent this from happening again.
Quote from: 2A03 on December 28, 2007, 12:41:07 am
I'll definitely consider soldering in a rectifier diode, especially after all this.
Wise decision, and a very good warning to all Twin Famicom owners ;).
This went on in my head when reading the conversation:
??? ? ... ? ... :( ??? . :o *silence*
What I've learned: Only use original stuff. Wouldn't want to kill my one and only Twin Famicom. ;D
I managed to replace the capacitor today and everything checks out!
I am surprised. I've put in the wrong polarity many times on different twins without them breaking. You must have done something else than just mix up the polarity?
Quote from: fredJ on August 11, 2011, 04:20:50 am
I am surprised. I've put in the wrong polarity many times on different twins without them breaking. You must have done something else than just mix up the polarity?
Nope, that was just it. I don't know why you bumped a three-year old thread though, especially considering that I don't even own the Twin Fami in question anymore (I believe Satoshi_Matrix still has it...).
Was it the red Twin Famicom?
I am trying to figure out why your broke when mine don't. :fire: Thank you for helping. :)
Quote from: fredJ on September 18, 2011, 02:12:31 am
Was it the red Twin Famicom?
I am trying to figure out why your broke when mine don't. :fire: Thank you for helping. :)
It was a black Twin Fami.