Mysterious circuitry hidden inside Famicom to Nes Adapter: Game converter US-72

I just acquired an adapter to play Famicom games inside an NES.
The thing works pretty well and comes with a nice casing and a ribbon to help taking it out of the system.



But the funny thing is there is little opening inside the connector with a window where you can see some hidden circuitry. I can see at least 2 transistors, 2 resistors and 1 ceramic cap.
AFAIK you do not need any extra parts for these adapters. The "official" gyromite one did not have any. So no need to say this has gotten me curious and I want to see inside it asap!



Problem is I cannot figure out how opening yet. There are no screw on this thing!! Looks like they glued it shut! I cannot see any evidence of screws hidden under the labels. I do not feel like peeling the labels needlessly or breaking it just to see inside. Anyone has opened one like that before?

Did you try looking under the sticker for screws?

Calpis wrote:

Not so mysterious--cheap converters don't have CIC  key clones in them; instead they zap the lock CIC in the NES with a  negative charge pump to prevent it from resetting.

Oh I see. I thought the Famicom used the cic too but apparently this thing is only in the NES.
I had looked at pics of the gyromite adapter but had not seen the CIC chip as they were all on the reverse side.
Thanks for the explanation
http://wiki.nesdev.com/w/index.php/CIC_lockout_chip

In the meantime I managed to open the damned thing. Turns out it is using self locking clips in an isolated spot. Basically they made the blasted thing pretty much impossible to take apart without damaging or breaking the clips.
Damn Taiwanese!  :p

So here is the not so mysterious circuit if anyone is intereste, both transistors are 2N3904.

3904 has to be one of the most common transistors.  I usually use 3904s for buffers.

In terms of engineering and reverse engineering taiwanese actually really impress me.  The street fighter 2 arcade hacks are made by the taiwanese including the bootleg cps1 arcade boards, also the gba tv adapter is from taiwan.  Taiwan makes some quality illegal hardware and software.

I have a big stock of 2N4123 here, I sort of inherited of them. they seem to be a good substitute to the 3904.