Ullrich von Bassewitz wrote: > On Sun, Jul 05, 2009 at 09:47:13PM +0200, Ullrich von Bassewitz wrote: > >> I've done the opposite quite some time ago and yes, it's the same as in the >> C64. As far as I remember, you have to replace VIC and crystal, and change a >> jumper. >> > > Looking at the schematics, I see no such jumper, so it's probably just the > first two. > > Regards > > > Uz > > > I swapped the VIC-II chip for the NTSC version, but not the crystal, and now I can at least view a black and white screen on a 1701 monitor. There is adequate heat-sink compound on the VIC -II. All things considered, I do have a PAL-compatible TV with composite video input, and I will probably return the original PAL VIC-II chip to the computer and use the PAL TV. On a related note... The FPLA's are 906114-02 and 906114-03. They run very hot. Not quite too hot to touch, but hot enough that I should have a fan on them while powered on. I am somewhat concerned about long-term use. I am running a step up/down power unit to power the computer. The voltages to the motherboard coming from the power supply are correct (+12V, -12V, 5V, 2.5V), the TIP29 transistor appears to be sending the correct voltages. I don't believe the power source is causing the FPLA's to run so hot, but I could be wrong. The computer appears to function just fine other than the wrong crystal for display output. My reason for using this computer is to experiment with it, but I don't want to ruin it either. I have newer 906114's (-04 and -05) that I could try to see if it makes a difference. The version of the BASIC ROMs are -02. Pictures: http://vintagecomputer.net/commodore/p500/ Bill Message was sent through the cbm-hackers mailing listReceived on 2009-07-05 23:20:28
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