Commodore 64 breakdown and clean

[RickR]

Found a C64 at Goodwill and it actually works!  It  needs a cleaning badly.  Very dirty and smells of smoke.  So here are some pics of the unit in its original condition.  Please note the cardboard RF shield -- Commodore was notorious for cutting costs everywhere they could, but this is ridiculous.  Take some pride, Commodore!  Sheesh. 

 

 

[MaximumRD]

Awesome find! It's in good caring hands now! 

[RickR]

Here is the finished product.  Sparkly clean, and it smells good too.  You can see the discoloration that has a nice sharp line along the very top edge. Weird.  I don't know which is discolored...the top edge or the majority of the top.  I think the majority...it seems too dark and not quite the right shade of brown.  Makes you wonder how the heck that happened.

 

The other nice thing is that the keyboard works a lot better now.  It needed several direct pushes on some keys before.  But now, back to normal.  Good ol' toothbrush with soapy water did the trick. 

 

 

[RickR]

Whoopsie.  Bad news.  No sound.  Could just be a blown fuse.  But that's a project for another day sadly. 

[Atari 5200 Guy]

Awesome find!  I agree with Max...it is in good hands now.  I would have to say that the discoloration is mostly going to be everything below the light-stripe on the top.  The inside of the machine should show you what color the plastic was originally.  

 

As for sound...if changing a fuse don't work you might try changing the audio IC.  How are you connecting it?  Can you use the monitor out to see if there is sound that way or, if you are using it, can you try the RF out?  Just trying to help with some suggestions and ideas.

[RickR]

I've tried RF and a composite cable. Both have the same issue. I also tried two different power adapters. But then ran out of time. Thanks for the suggestions, keep them coming! When I get time, I'll open her up and probe with a voltmeter. My hope is that it's just a fuse on the 9V line.

[RickR]

The fuse is fine.

PIN 28 of the SID chip is 12V, and PIN 25 reads 5V, so the board is fine.  I think the SID chip itself is broken.

 

Does anyone here have a spare?  Or maybe a broken 64 I could use as a donor? 

[Atari 5200 Guy]

I think Lance at V61 knows someone that use to deal with Commodore stuff.  He might be able to point you in the right direction.  I'll see what I can find.  I don't have a C64 myself so I can't help in that department.

 

So far I found a place that sells them...but they are in the UK.  I'll share the link should you be interested.  

 

http://store.retroleum.co.uk/c64-chips

 

They recommend placing a heatsink on the SID to keep it from overheating.  I"ll post more if I find them.

[Atari 5200 Guy]

I found this, too...

 

http://www.80svc.com/index.php?rt=product/category&path=3_5

 

But the SID from here might cost more than you want to pay.  I'll keep looking.

[RickR]

UPDATE:  I got a spare SID chip from a really nice guy on Facebook.  Popped it in, and now the sound works PERFECTLY!  WOOOHOOOOO!