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B/W C128


I have a PAL c128 that outputs its video signal Black and White. I checked/tried the followng things, whitout success:

- Checked the continuity of the trace from pin 6 in the video connector to the R/C modulator color output.
- Checked the continuity of the trace from the R/C modulator color input to the Pin 16 of the 8566R3.
- Replaced the 8566R3 with another one i got from ebay.
- Replaced the R/F modulator with this little board: https://oshpark.com/shared_projects/joo55sLQ
- Replaced C62, C63 and C88 electrolitic capacitors with new ones. (the ones inside the 8566 metal case)
- Tried do adjust the C20 rotating it a little bit.

After all this, the image is still B/W :(. I'm getting out of ideas... any suggestion on the possible cause?


P.D: i know it's unrelated, but i also replaced the original power supply with a custom new one made with a 5V power supply and a 9V transformer, both exceeding the required amperages.

I'm no expert but I've seen something similar re:B/W C128
One of the videos I watched it was explained that hooking up a 50 hertz pal Xbox to a 60 hertz NTSC monitor results in a black and white image. Perhaps your having the same issue? Is the CRT the Pal C128 is connected to a NTSC monitor/tv? I apologize in advance if this scenario isn't applicable, sounds like you know more than I do, just thought I'd throw it out there.
re: B/W C128

This is not the case. All the equipment i'm using is PAL, but anyway, thanks for your answer, Brewskii.

Update: I've also tried to replace the 8701 IC that generates the oDot and oCOLOR signals for the VIC chip. No luck, it's still B/W.

Its a good point that on both
Its a good point that on both PAL and NTSC if the master frequency is off you will lose color lock, Usually you can see rolling or "racing" rainbows.
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