Bill Machacek, check your boards. There is a Commodore 64c rev.A and rev.B. The 64c boards have the following texts: PCB ASSY NO. 250469 and PCB NO. 252311 REV.A (or B on newer boards). The difference between the two revisions is in the Gate Array chip: The one in rev.B includes COLOR RAM.
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Bill Machacek, check your boards. There is a Commodore 64c rev.A and rev.B. The 64c boards have the following texts: PCB ASSY NO. 250469 and PCB NO. 252311 REV.A (or B on newer boards). The difference between the two revisions is in the Gate Array chip: The one in rev.B includes COLOR RAM. The first C-64 models still had a five pin jack, like in the VIC-20. Shortly after that an eight pin jack was built in, providing the additional chrominance signal. Great information from [http://www.c64-wiki.com/index.php/Main_Page|here.] Hope this helps, good luck.
Bill Machacek, check your boards. There is a Commodore 64c rev.A and rev.B. The 64c boards have the following texts: PCB ASSY NO. 250469 and PCB NO. 252311 REV.A (or B on newer boards). The difference between the two revisions is in the Gate Array chip: The one in rev.B includes COLOR RAM.