Famicom to NES adapter compatibility problems.... works again

[Finfami]

I have Famicom to NES adapter (picture attached) that refuses to work in original front loading NES which has lockout chip disabled. I have tried games in both ways and also took the PCB out and tried it in both ways to nope, it doesn't work in original NES. The console I have generally works well with all cartridges, usually no need to reseat and do other tricks to get games running.

However, my chinese toploader clone has no problems using it, also if I first use 60-72 pin adapter, then place this on top of it and connect game it works with my genuine Famicom. So it seems that the adapter is built in such way that it is incompatible with the original NES?

[mammal93]

I have this same adapter, and the same issue. My brother said he thought it was because of the lockout chip, but you say yours is disabled? When I got mine off ebay they did say it was only compatible with top loaders, but my brother (who knows way more of the technical stuff) said he can't tell why other than the lockout chip. I gave up and got an actual Famicom instead, which is great. Sorry I wasn't any help 

[Finfami]

Yes I disabled the lockout chip in order to test if that was the problem. Probably some pins in in the adapter aren't connected as they should be in order for this to work in NES  
Very strange if that's the case, I would think that whoever designed and sold this would have much broader market if it would work in the original console design.

I also browsed eBay and noticed that indeed these are still for sale and sellers say that the original NES is not supported.

[mammal93]

Yeah pretty much everyone has an original NES haha. Yeah it's disappointing since I don't know if that's fixable. Like I said I don't need it anymore, but my brother doesn't want to buy a Famicom so I gave it to him thinking it was just the lockout.

[FAMICOM_87]

trace the connections with a multiced here is the scheme
http://i54.photobucket.com/albums/g113/IBMDOS/MODS/AEN.jpg

BTW I am using this adapter no issues at all with original consoles it even have a cyclone IC (lockout chip)
https://www.aliexpress.com/item/FC-60Pins-to-NES-72Pins-Adaptor-PCBA-with-CIC-chip-installed/32689925531.html?spm=2114.40010208.4.8.KiEPSF

[Finfami]

I'll take a look later today.

I have another adapter whch works on my NES and has a strap allowing easy removal so I was going to sell this problematic adapter anyway, surprised that it doesn't work in original console.

[Finfami]

Well funnily enough the adapter no longer works in any console.

After noticing that I used multimeter and all connections seem to be fine, I even went as far as resoldering those couple contact points. I did quick measurements and everything seems fine but it just doesn't work. Games and consoles all work, only this adapter doesn't. Pins on the NES connector side are very clean and good condition, on the Famicom cartridge slot I don't see anything obvious, I sprayed some contact spray and used credit card / paper "trick" to try cleaning them.

The only thing I can think is that the excessive force required to remove this from toploader clone was too much for it, it was extremely difficult to get removed.

[FAMICOM_87]

may be the PCB is too thin and do not make good contact , compare it  whit for an example cartridge PCB 

[Finfami]

It worked at first, it could be that the cartridge slot in the clone console would be dirty or pins would be messed.... but the console works with standard nes cartridges and also when using NES to Famicom adapter and this Famicom to NES adapter it no longer works in original Famicom as it did at first.

Removing it from that toploader clone require very much force and of course I could only pull from the cartridge slot edges, it may very well be that the slot or PCB got damaged somehow and no longer connects properly... even though according to my quick mesurements everything should be fine.

Thankfully I don't need this and even if I did, they are cheap, just surprised that it suddenly doesn't work. Good thing that I didn't sell it to anyone although I usually do final test before packing.


UPDATE: It is connection issue, I took a look at it again under bright light and noticed bad soldering. I did some resoldering and now it works again.   One pin was loose but when I measure I pressed down with the other probe, just enough for it to make connection I guess so I didn't notice that.

It will fail again if used in that toploader, I'm sure.