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Does anyone know of any Sharp Twin Famicom mods? I bought one that I though was broken from Yahoo! but it turns out it's 'broken' because a wire on one of the mods has fallen out. I didn't know it was modified when I bought it but I'm curious as to what it could be doing.

I took some pictures, maybe someone knows this mod from an older GameLab or Backup Technique magazine article, though I wasn't sure what would be most helpful to take pictures of:

What does the outside connector (shown in the 1st and 7th pics) --which those wires go to -- look like? Could you take a pic of that? I'd say initially it looks like an extra controller mod, but I'm no expert. It could be anything...

You're going to have to make a schematic of what exactly the mod is, i.e. where every wire goes and comes from, and the pinout of the connector in regards to that. once thats done, it should be pretty obvious what the mod does and where those two disconnected wires should go.

LN

A twin famicom might mean a disable copy protection mod?

Are any board traces cut? Is the chip in the disk drive a FD3206 or a FD7201?

I don't know what the mod is, but a copy protection mod wouldn't have a switch on the back, let alone a 6 bit toggle switch. Where does that red toggle go and is that LED next to it on all Twins?

It appears that 2 blue wires are not connected or one or the other fell off the solder point on that 6 bit switch, though...hard to say. It appears only 5 switches are used with a space between the first switch and the other 4. I'd have to bust out my Backup technique issues and look...It wouldn't be in any Gamlabs...it would be within probably the first 10-14 BT issues. What month of what year did the Twin come out? That may save me from looking through a few issues. I still have a bunch of old copies for sale, BTW. shameless plug ftw.

If I had to guess, it is a dubbing circuit. Is that a potentiometer on the outside or another LED? The LED(s) and knob is used to sync the two machines together, iirc. However, if that's not a knob, then I have no idea, and I still really have no clue what the switches are for (EDIT...never mind, that's the disk power LED). Why would one want to switch between 32 states of anything on a FC? Or, if the first switch is just to denote whether the mod is "On," and then there's 16 states of something. I dunno.

-Rob

It's exactly the same thing as what's in Backup Technique (Flip-flop and NAND glue to correct writing), I'm just curious about the switch. Where does that connect?

Yep, that's the copy-protect-defeating circuit, though they use one less IC that the one in Famicom Kaizou Manual (volume 2 or 3, I forget), not Backup Technique. It was just a 3-off sister mook of Backup Technique.

Some of the wires must go into the disk drive unit, right? There must be some traces cut on the board by the power input are, I'd imagine.

Perhaps the switch is to turn the protection off or on? I still don't know what the 6-bit switch is for.

-Rob