Vince Briel wrote:
Could the 555 timer chips cause the problem? Or the crystal? I'd like to get this board running to have a spare onhand.
If you get Text on the screen, the video circuitry works, and so does the crystal. One of the 555, I think the one near the left edge in the second lowest row of chips, is used to blink the cursor or blinking text in general (rather irrelevant in your case), the other one is used to create a reset pulse. You might look for 6502 docs on the net and then measure the voltage on its /RESET pin relative to ground. If it's 0V then the machine is constantly doing a reset and yes, the 555 would be a candidate.
-- Linards Ticmanis The Master said, "The business of laying on the colors follows the preparation of the plain ground."