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Hey guys, I have a Twin Famicom that I'm going to sell because I never use it. I know it works, but just to be sure I want to test it before I sell it. it never came with a power supply, so I've always had to improvise. It requires 9v DC as to be expected, but I notice that it's center core positive.

I have a Genesis 1 PSU that will fit the port, but it''s center core negative. I know the NES 001 is pretty much invincible, but would I damage the Twin by using the Genesis PSU? Otherwise, I have to use a universal PSU with a switch for polarity. Thanks for any help guys.

edit: just noticed the genesis ac doesnt even fit! still, the question remains about the importance of polarity on the Twin.

Im not sure if this will help, but here is an article covering some of the issues you stated:

http://www.vintagecomputing.com/index.php/archives/342

It says a Genesis PSU will work fine if the polarity is rewired for the connector, since the voltage regulator is fine handling 9v.

SatoshiMatrix wrote:edit: just noticed the genesis ac doesnt even fit! still, the question remains about the importance of polarity on the Twin.

BTW, it's not a good idea to plug it in to the Famicom, even if it's off and unplugged from the wall. The power adapter probably has a capacitor in it that can stay charged after it's turned off, and the Famicom could have things connected directly to the jack, before the power switch (for example a capacitor as well). Thus when you plug it in, you could deliver the wrong polarity. After I damaged my SNES due to something similar, I'm more cautious. If I were doing this, I'd first have used the Genesis power in a Genesis, leaving it on and unplugging it from the wall, so that it discharged everything completely. Then the wall adapter would be known to harbor nothing damaging.

You might as well note that it needs a certain type of adaptor size and polarity, since it doesn't come with the original power supply. I imagine it just won't work with centre tip negative.