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View Full Version : PAL COMMODORE WITH 14 Mhz Xtal ??????



SUCCESS
November 22nd, 2009, 05:25 PM
Hi people,

I've just bought a C64 PAL-N, which was manufactured by Drean in my country (so it's a Drean-Commodore).
I't the second PAL C64 I have from Drean and both have 14.318 Mhz XTAL. I can't understand this. It's supossed that PAL need a 17.7 Mhz XTAL.
At first, I though that some repairer put a wrong one, but then. I opened the second and it's the same. Both have the 14.318 Xtal.

Anyway, I'm, trying to fix the one I bought. It's a 1982 board with the VIC-II in CERDIP package. The VIC-II is actually a 6572R0 (PAL).

What happens ?

Ok, when I turned the computer on, the image stays in blank (black) for a moment (like any C64) but then start to show horizontal strips all around.
The strips are very short and tiny and have nothing to do with the C64. No caracter or graphic is visible.. If I turn it on and off several times, the ligh blue screen sometimes appears, but with incorrect size (small).
If I press play, motor doesn't spins. That's very rare....

I managed to see the clock signals, and looks fine. There's something like 1Mhz at the 6510, and the PLA address signals for each roms show activitiy.
Voltage is present and chips got warm (but not hot) as expected.

I'm very confused about this ... any idea ????

Many thanks for reading and your comments will be greatly appreciated.

Pedro