Famicom b&w problem

[X]

Hi! need help from Famicomworld guys...

I have recently bought a Famicom from a yard sale when suddenly... it turns out to be black and white display only... now i didn't yet tested it with another television. but why is my other famicom displays colored. and they both are unmodded. and both are authentic. I use a SNES RF adapter of both of them. I'm just wondering what's wrong with the other... Please give advice. Thanks!

Regards,
Ron

[P]

Are you in a PAL region? You are lucky if you get both a good picture and good sound on a PAL TV with RF. Black and white happens if your TV doesn't support NTSC colors that the Famicom is sending. Even modern PAL TVs that support NTSC usually don't support it in the RF outlet.

But you say another Famicom works on the same TV? Does it say Hong Kong version or something else on it? Is the picture clear but black and white? How about sound?

[X]

both famicom are ntsc. both are nintendo geniune... btw, i'm in asia.. so usually its ntsc here. yes yes both sound are okay. it's just the other one displays only black and white. Thanks for the reply!

[80sFREAK]

It's possible, when XTAL oscillator frequency drifted. Might appear on certain TV's.

[X]

hmm.. that's also what i'm thinking.. to try other television. and oh... an oscillator problem i see. thank you.

[80sFREAK]

There is green plastic(total rubbish) trimmer on PCB, you can try to adjust it - quarter turn clockwise, then quarter turn counter clockwise. It will clean contacts of trimmer and might solve problem. Keep in mind, one of pins connected to "screw" head, so when you touch it with metal screwdriver, picture will becomes distorted and CPU might "stuck"

[X]

i see that is way sensitive. i'll try your advice. thank you very much 

[X]

There is green plastic(total rubbish) trimmer on PCB, you can try to adjust it - quarter turn clockwise, then quarter turn counter clockwise. It will clean contacts of trimmer and might solve problem. Keep in mind, one of pins connected to "screw" head, so when you touch it with metal screwdriver, picture will becomes distorted and CPU might "stuck"

thank you Sir. my spare unit is finally showing color display. oh.. its been a year. been busy with these days. heheh anyway.. this helps a lot.