I'm repairing a friend's Colecovision and it's giving me serious headches. To help the diagnosing process I've even opened my Adam to make some changes over it; so after socketizing the Adam VDP and scrapping the glue of the cooler I've found this little thingie:
I was expecting a plain TMS9928A[NL]; yep, it must be the Texas IC rebranded of course; but the weird thing is that after testing 5 spare TMS9928A I've recently purchased, no one gives me a display, only the original works.
I have two possibilities:
1) It's not a TMS9928A and it's a slightly different chip. It's an NTSC version, I think; I've not checked it as I came from the USA.
2) All the spare ICs are bad or fake (yes, they came from China...).
Does anyone know more about the Adam VDP or even has replaced it successfully?, could it be a 9918?