I was recently given a c64 by a friend across a the country. Before he shipped it, he tested it and confirmed it to work. I received it a few days ago and when i plugged it in and pressed the power switch, the led light came for a second then turned off. It wasnt plugged into a tv at this point so I dont know if it actually booted up. Anyway, i proceeded to plug it into a tv but get nothing but a black screen as opposed to static. So far, I have reseated any chips that i could as well as check the fuse, which was fine. I have also checked the psu which reads 10.1 v on pins 6 &7, and 5.9 v on pins 5 and 2(?). Not sure what else to do. Does anyone have any advice?
So, if anyone is interested, the psu was bad. I suspect it was alread going bad, which is a common issue with c64 psus. Ive ordered a new aftermarket psu and hopefully no chips were destroyed by the old one.
So the power supply was the issue after all. Hopefully the new PSU gets it going again. If you haven't already, get an s-video cable for the C64. It will give you much better quality than the RF and composite video cables. An RGB mod may be possible in the future, but it seems to be really hard to do and may require something like the Tim Worthington's NESRGB.
It's the VIA chip. It only outputs Y/C which can be used for S-Video on most TVs (not 100% proper S-video as C64 predated proper S-Video standard) and also combined for composite and fed through RF modulator. A replacement VIA chip will be needed. Like Nintendo's PPU.
It predates modern S-Video? Do you mean the connectors or the actual Y/C signals? If it's the signals, what's the difference between C64 Y/C and modern Luma/Chroma? I know the official cables used two RCA plugs for S-Video (one for Luma and one for Chroma) and many aftermarket cables use 4 pin mini-DIN. I actually have an adapter that combines the two RCA Y/C jacks into a single 4 pin mini-DIN S-Video connector. It doesn't have any branding and I can't seem to find these online. I thought about getting a C64 one day along with the official S-Video cable, it would give me a reason to use this adapter. Would the whole chip need to be replaced (similar to the old NES RGB method), or would something like the NESRGB (new method; uses original NES PPU to generate RGBS) work? Since it is a computer, 31KHz RGBHV over VGA would be a nice thing to add to this "C64RGB" board too.
The signal itself. the C64 actually didn't have separate Y (luminance) and C (color) outputs. It had the luma, but used the composite video signal for chroma. I have no idea at this point. To get RGB out without replacing the VIC an add-on device would have to monitor address and data lines and create the image in internal memory using C64's fixed 16 colors, then convert them to RGB signal. On most C64, VIC are not soldered in but rather socketed so it would be easy to create a plug in replacement chip or adapter board with original VIC for C64 to communicate with.
