Vic 20 Repair

The Vic 20 was dead and only showing a black screen, I wasn't expecting to have much luck with it either because from what I've read it's usually the custom CPU or VIC chip that dies in these. I didn't have another Vic 20 or any spares but I gave the motherboard a quick looking over anyway and checked the socketed chips were making good contact.

Before putting it back together and storing it away I noticed the previous owner had socketed three logic chips near the cartridge socket, 74LS374 if I remember correctly. I decided to swap these around since they were all the same and to see if it made any difference. To my surprise this brought the computer to life with just some minor graphics glitches, after replacing the bad TTL it is now fully working.

Wow I thought jailbars on the Mega Drive were bad...