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hi all im new here
i recently dug out my apple //c and wanted to feel that nostalgic rush. the //c is not working however. here is what happens.
when i flip the power switch there is garbage on the screen. i try pressing the white apple key,control, and reset keys and it seems to make the image change in very minor ways. turning the power off then on again sometimes changes the screen where all the characters are jittering. see it in the attachment
when i flip the power switch there is no beeping. i know there supposed to be one beep at least. also the power light stays on, but the disk access light does not light up at all like its supposed to; just as well, the internal disk drive does not spin on startup and there is no disk in the drive.
there are no peripherals connected to the computer: only the PSU and the composite video cable (not 15 pin connector) are plugged in. also i the video cable plugs into my HDTV
i have tried opening the computer and reseating the 4 chips that can be removed but the exact same problem exists. please help!
Before starting this or any other endeavor with electronics, discharge any static from your body (and use a anti-static wrist strap) to protect the fragile IC's, and discharge any capacitors in the circuit for your safety.
These things are old enough now that besides the remedy of reseating the IC's as you did (to correct any thermal chip creep), there can be micro oxidation on the surfaces of the pins and sockets. To remedy that you should take them apart and clean both the chips and the sockets with some anhydrous alcohol (from an electronics or chemical supply house) and a clean toothbrush. There were other bits of hardware that also use connectors such as the cable for the keyboard. These should also be cleaned and reseated.
Good luck,
Mutant_Pie
From your description and picture, I would say the CPU has gone bad.
If you have pulled and reseated the CPU a replacement is probably in order. I have seen the same problem before and a CPU (65c02) change out fixed it back to working condition.
im going to try and save the computer by cleaning with anhydrous alcohol first. if that does not work will this IC work as a replacement?:
http://www.westerndesigncenter.com/wdc/w65c02s-chip.cfm
thanks guys for all your help
repost
I think your problem involved memory errors. Replace the chip of memory. How to you get this chips? No have idea.
ok so memory is a possible failure. i hope not. but i still need to know if this IC will replace the processor if its bad
http://www.westerndesigncenter.com/wdc/w65c02s-chip.cfm
thanks guys
Yes, direct replacement.