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VIC-20 in-box $1 ... Think it's busted though...
Posted by: classic mac 500 on 2007-10-23 14:15:14
Hey there everyone... It's been a while since I've posted. I wanted to say to those who've PM'ed me, I will follow-up with you in time. My mind's been all over the place as well as my emotions... That's a story for The Lounge, which I'll post later...

At our local flea market, I found a VIC-20 in the box with cartridges, paddles and a joystick and everything needed to hook it up for $1, but sadly I think it's busted. I hooked it up, flipped the switch, red light comes on the VIC-20, but nothing on the screen. One of the chips is fried I presume?

I'd appreciate any help anyone could give me. 🙂

Posted by: Bunsen on 2007-10-23 14:39:23
Should you be in Australia, I'll gladly refund you your $1 + postage for the empty case 🙂

Posted by: classic mac 500 on 2007-10-23 14:51:38
Hey Bunsen... I'm sorry... I'm in the states (South Carolina). :-(

Do you have a diagnosis or is she terminal? :-(

Posted by: funkytoad on 2007-10-23 16:36:30
Too bad it is having problems.

Nice to hear from you!

And sorry about everything that has been going on. 🙁

Posted by: tomlee59 on 2007-10-23 20:49:52
There's not much in a VIC-20, so there's not much that can go seriously wrong. 🙂

Check the usual easy stuff first -- do a careful visual inspection of the logic board. The 6502 and the VIC chip are typically socketed, and Commodore used very cheap sockets. Simply (and carefully!) removing and reseating any socketed chips may fix the computer. It's been so long since I opened one up that I don't remember if the RAM (all mighty 4kB of it) is also socketed, but if so, you know what to do. Just work slowly and carefully so that you don't bend any leads while reinserting the chips.

Check for capacitor leakage, as you would any old electronic thing.

Also verify that the RF modulator (if that's how you're hooking it up to the TV) has clean connections to the VIC. Double-check the connections to the antenna, and make sure that the TV is tuned to the same channel that the modulator is.

A thorough visual inspection will quite frequently pinpoint the problem. The semiconductors themselves rarely rot.

Btw, here is a link to some nicely-scanned schematics: http://www.mainbyte.com/vic20/manuals.html

Posted by: MacNoob on 2007-10-24 06:21:13
POWER SUPPLY

says the former Commodore salesperson/support person.

Assuming everything is otherwise hooked up correctly.

Posted by: classic mac 500 on 2007-10-26 16:23:28
Here's an update... I cracked it open... 1 of the IC's was cocked a pretty good bit out of its socket. Even when I pushed it in and checked the rest of them, STILL no joy. I left it on for 10 or 15 minutes, none of the IC's got hot, so I don't think any of them are bad. I even tried a different power supply I already had, and still nothing.

Any ideas?

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