Fixing a Busted Commodore 64, and Viewer Mail!

[@ownpj]

Never put a working VIC2 chip into another board without checking the two onboard voltage regulators first.

[@JoesComputerMuseum]

I tested them off camera before hand. But, noted for future. I don't want people to copy my bad technique.

[@rivards1]

You can randomly grab almost any Apple II from Craigslist and there is a 95% chance it works. A random C64 of the same age has a 95% chance of NOT working.

[@JoesComputerMuseum]

;)

[@geekwithsocialskills]

Original C64 power supply bricks are known to take out VIC-II, SID, PLA and RAM chips. Anyone with a C64 and has the original power supply needs to stop using them right away and get a modern replacement like you have. You can build them with parts from Digikey and Mouser for under $40.00 USD.

[@JoesComputerMuseum]

Good note! That's how I killed the SID in my first C64. Turned it on, weird noise from machine, then no noise ever again.

[@geekwithsocialskills]

Yeah, original C64 power supplies work until they don't, then they shoot high voltage all through your machine and kill all sorts of chips. Bad design by Commodore back in the day. At least now there are modern safer power supplies along with system savers to pop a fuse before killing a machine.

[@lemonherb1]

Hey Joe, one of the things I do for immersion retrobrite is I use small glasses and invert them in the tub so there's peroxide inside and place that over the item I'm treating. That way the surface where the glass is gets exposure to peroxide and UV. Ov course that works OK for relatively level items. I note that the C64 case top slopes forward so something else might be needed to hold the front down. maybe clear fishing line to a weight, or maybe using the posts for the case screws to attach to some weight from below? Anyways, this was another educational and entertaining episode. Catch you later!

[@JoesComputerMuseum]

Great suggestions. Thanks!!

[@DrDavesDiversions]

14:06 Subscribed and catching up on your stuff, Joe! See, through-hole on surface-mount is where it's at! :)

[@JoesComputerMuseum]

:D

[@MartinPaoloni]

LOL, I've been shouting to my PC for like 20 minutes... "No blinking cursor!!! It's the CIA! IT'S THE CIAAAA!!!" but somehow you didn't hear me. 🤣 Good thing though, cause I was wrong! New sub btw. Kudos for the great content!

[@JoesComputerMuseum]

Literally my first dead C64 repair. I think I did a satisfactory job. And now that I know more, the next time will be an excellent job!

[@MartinPaoloni]

@@JoesComputerMuseum I'd say it was more than a satisfactory job. 😉 Take care!

[@L.C.A.car_adventure_channel]

A very great video, learned allot. Bought today also a Commodore C64 II and hope it will arrive per Mail soon.

[@JoesComputerMuseum]

:D

[@francoisleveille409]

As a replacement for the 8701, I've been offering TOLB since 2017 and it doesn't require assembly or tuning your C64's variable capacitor. See: www.melon64.com/forum/viewtopic.php?f=34&t=4055

[@JoesComputerMuseum]

Care to send me one for review and comparison?

[@francoisleveille409]

@@JoesComputerMuseum I'd be glad to but I don't know how to get your shipping address.

[@JoesComputerMuseum]

@@francoisleveille409 send me an email to joe at jcm-1 dot com

[@francoisleveille409]

@@JoesComputerMuseum Message sent!

[@GrandmaHatesTech]

Wow. I remember my son having one of these when he was young. It's like going back in time.

[@JoesComputerMuseum]

Yep! The C64 is a special old computer, that's for sure. Folks who love them, love them immensely.

[@Miidolf]

Enjoyed watching this video. Did you double check the VIC-II chip just to make sure it was busted? (Might have been neat to see it's symptoms after you replaced the 7701 chip). Also with what chip did you actually replace the faulty logic chip? Thank you in advance :)

[@JoesComputerMuseum]

I tested the VIC-II off camera on my other C64 (for video flow). It definitely does not work. The faulty logic chip was replaced with a 74LS139. The schematic I showed on screen was VERY WRONG.

[@airix10]

As soon as I heard you mention "retro bright", I already got a foreboding feeling. The naturally occuring oxidation is part of the character of old microcomputers and Nintendo consoles, just let it be! The color was cool, just needed some cleaning. They are going to oxidize again anyway and you're just going to deteriorate the plastic if you keep trying to rebrighten it.

[@JoesComputerMuseum]

On the whole, I agree. I usually do not retrobrite.

[@JoesComputerMuseum]

@@airix10 Thanks! No formal training or degree. I work in Information Technology.

[@lanatrzczka]

That TI monitor is a real gem! Did you have to do any recaps or other fixes to it?

[@JoesComputerMuseum]

Nope. It just works. And I have two.

[@Chris40N180]

Great video. Did you retest the VIC-II to make sure it's actually bad?

[@JoesComputerMuseum]

I tested the VIC-II off camera on my other C64 (for video flow). It definitely does not work.

[@justinthomas2458]

You should try the creme peroxide saran wrap method

[@JoesComputerMuseum]

Summer.

[@JVHShack]

Hey, Joe. Would the seller of the C64 that you resurrected have another one to sell presently? I'm looking for a good deal on one.

[@JoesComputerMuseum]

Maybe? Check my about link on my channel and send me an email.

[@jafirelkurd]

The PLA isn’t such a big deal anymore. There is a GAL replacement that works pretty well. I learned about it from Adrian’s Digital Basement.

[@JoesComputerMuseum]

Agreed!

[@ohioterran7374]

Great job on fixing that C64!

[@JoesComputerMuseum]

Thanks!!

[@GORF_EMPIRE]

Suggestion..... take a flat steel plate and put a couple holes in it so it lines up with a couple of the screws of the case, screw it in and let the weight keep it down in the tub.

[@JoesComputerMuseum]

Yep!

[@natethefighter]

"Have to be smarter than the box" - my mom used to say that to me ALL THE TIME

[@JoesComputerMuseum]

:D

[@johnrappids1389]

YOOOOO joe! knowing is half the battle!

[@JoesComputerMuseum]

GI-ME!

[@0toleranz]

Haha you killed me at „different kind of ugly“. Nice repair. I didn’t know Jeff does the timing generator replacements, I have two defective ones out of my machines. Regarding no video, how are you doing with the other one that has no video - the JCM1 ? Greetings from Germany.

[@JoesComputerMuseum]

Hey, yeah - his timing generator is spot on. JCM-1 has taken back burner to these other repair projects. It's still on my mind. I will get back to it some day. Video will probably take a different turn, however. There are much easier cheaper ways to do it, but still keep the old 8-bit charm.

[@tiemanowo]

5:39 don't you think that before you try a 'working" chip, it is wise to check voltage regulators? If there is something wrong with regulators your "working VIC" is no more :) ps. anyway. nice video

[@JoesComputerMuseum]

Yes. I must admit, though, I did some Movie magic. I had tested some stuff before filming. Noted for future.

[@TheLemminkainen]

VICII is in FPGA now :)

[@griftereck]

good to see an informative video

[@JoesComputerMuseum]

Glad it was helpful!

[@SebastianSnoeck]

It is not logical to not test before you do everything is to the 5 volt and 12 volt in the commodore

[@brostenen]

I am curious as to why NTSC is good, when it comes to C64. Just curious.

[@JoesComputerMuseum]

In this case, it's because I'm in the United States, and I only have access to NTSC compatible monitors and US power supplies.

[@brostenen]

@@JoesComputerMuseum Ahhh... I see. If you wish to get PAL machines running at your place, then I can highly recommend an Retrotink X2 Mini. It is the best for C64 for the price.

[@tombarber8929]

Might be worth painting that C64 case. While it won't be the original color, it'll should look nice! Adrian's Digital Basement has a good video where he talks a bit about painting them. kzbin.info/www/bejne/rKvMqoecfZt6f5o

[@JoesComputerMuseum]

Yup! I have another idea on it, though. Might be a while before it comes about. Think "automobile".

[@piratestation69]

Definitely not a paper weight like the MACs... Always nice to see a true piece of history be restored. I had the same problem retro brighting a SNES case... Same results. Fail... RIP SID chip. Seeing the SID can't be dumped, what type of chip is the SID? To bad someone can't fabricate the exact chip or the SSI-263 speech chip for that matter. I like to have backups...

[@JoesComputerMuseum]

The SID is a custom sound synthesizer, the first single chip to do that, in fact. There are already replacements for it, though.