Commodore C128 Repair - First time fixing the Amazing 8-bit powerhouse - Bad Ram, Bad PSU, Bad CIA

In this video, I get to know the rare-to-me Commodore C128. Repairing the faulty power supply, then moving on to a bad ram chip on the motherboard, and finally a faulty CIA chip.
Paul (the owner)
/ underwulde123
RetroBitsTV Matt
/ @retrobitstv
Petter Hans (Bwack)
/ bwack77
/ @bwack
github.com/bwack
SECOND CHANNEL!
/ @morefunmakingit2
More Fun Website
www.morefunmakingit.co.uk/
My Twitterings can be found here
/ morefunmakingit
Discord Channel
/ discord
Ko-fi page
ko-fi.com/morefunmakingit
Amazon Wishlist
www.amazon.co.uk/hz/wishlist/...
00:00 Intro
00:47 Power Supply Problems
08:29 First Switch On
11:16 Hot Switch
12:00 Second Switch On
13:06 Discovering the Bad Ram
15:14 Replace the Switch
17:38 Dead Test
17:59 Replacing the Faulty Ram Chip
20:50 Making a C128 Diagnostic Cart
22:29 Intermission - CIA Faulty
26:25 Conclusions
#c128 #commodore #retrorepairs

[@retrobitstv]

Glad you were able to get the old girl working again and thanks for the shout-out! The C128 remains my favorite 8-bit home micro. While there's not a ton of 128-specific software, there are some real gems in and amongst what is available. Lots of hardware upgrades too. With the right kit, you've could have had a budget terror that would have given the early Macintosh a run for its money for a fraction of the price, played all of the games in the C64 library, and went online at blazing (for the time) speeds :)

[@MoreFunMakingIt]

Thank you for your excellent and super useful content!

[@lovemadeinjapan]

Girl... ? Seriously. This is a bloke. The PSU alone has more steroids than the Hulk. Off course, a C128 has multiple personality dissorder, maybe the Z80 inside is girlish, it must be Cinderella burried in a dark pit with humming machinery. I have it here on my desk, and no matter how hard I try, no lesbian feelings coming up. It is the weirdest piece of 8-bit shit ever built.

[@joopidema]

First time I was shouting at the screen when you opent the PSU with the 230v power still plugged in. LOOKOUT! Second time I was shouting at the screen when the keyboard was missing some keys in a pattern IT IS THE CIA!😂. Well done. I really like your repair video’s. 👍🏻

[@EgoShredder]

The PSU is okay ONLY if you know exactly what you are doing, and are fully concentrating. Otherwise NEVER DO IT! 😁

[@MoreFunMakingIt]

😆 Sorry to make you shout! PSU was powered down. Stuff like that doesnt always get through the editing stage.

[@weepingscorpion8739]

I love the Commodore 128. My dad bought one around 1987 and it saw pretty much continuous use for over a decade. Then it started failing and now it has mainly be collecting dust the poor thing. I am determined to get it fixed however, so hopefully one day that will happen. Like many other C128s ours was mainly in C64 mode. A shame really but the C128 was then and is still now really underrated and there is still so little native software for it, as in games of course. Ultima V had a native C128 port (it adds music during game play which the C64 does not have) and even The 8-Bit Guy's Attack of the PETSCII Robots has a native port. Great video, Lee!

[@MoreFunMakingIt]

Lucky you! I would love a 128. Good luck getting it fixed 😄

[@domramsey]

Appreciate this as I took delivery of a C128D that had been dropped from a great height yesterday!

[@MoreFunMakingIt]

Oh no! Hopefully you can piece it back together. Maybe make a feature of the damage.

[@domramsey]

@@MoreFunMakingIt Literally just got it booting by reseating all the socketed chips. A lot of the plastic is cracked but you can barely see that when it's on a desk. Just don't pick it up!

[@wimwiddershins]

The IR camera really helped point out that dodgy switch. Funny how many high resistance faults I've seen lately; switches, contacts and especially crappy USB cables that drop a volt over less than a metre.

[@MoreFunMakingIt]

It really has proved to be a very useful addition to my toolset. Saves me a lot of time. I've managed to get it hooked up to the bench laptop now too. Makes using it even more convenient.

[@Rockythefishman]

Nice repair, she lives again. One of the few machines I have never missed with.

[@MoreFunMakingIt]

Thank you! It was nice to work on. I'm glad it wasn't a more complicated fault though 😆

[@binarydinosaurs]

I remember chatting about those topdon cameras the other week, this has convinced me. Splendid!

[@MoreFunMakingIt]

It has transformed how I diagnose faults now. That's not to say its always going to be the tool that gives you the answer, sometimes the fault isn't a short. But, especially on Commodore machines and MOS silicon, it has really made the difference.

[@bwack]

Great. I wonder if I keep forgetting to send the comment. Lol. Good to see another Versa64Cart in the wild. I have jupiter lander as well as dead+diag test on mine, but i struggle with the jumpers😅 Sven Petersen made a diagcart that is based on the Versa, but is optimized with sliders to automatically set the memory mapping jumpers when switching between diag and dead test.

[@MoreFunMakingIt]

My dead test and C64 diagnostics cart is that exact Sven Petersen one! I ordered a bunch of Versa cart boards plus some of Svens Diag64 boards to make some variations up and give some away to friends.

[@rimmersbryggeri]

You can fix the strain relief by threading a nylon or fiber washer over the cable and locking it in place with the cable tie.

[@jackleg693]

Another superb video! I don’t fix old computers, I don’t even play games. I’m not an electrician or anything similar yet I find these videos so good to watch!

[@MoreFunMakingIt]

Love seeing your comments J! 😍

[@DaveVelociraptor]

Delighted to see contact cleaner being used

[@MoreFunMakingIt]

"Dave Juice"

[@RetrogradeScene]

I really want to spend some more time playing around in the Commodore world. Never had thee chance to play on a 128. Nice fix as always!

[@rossbennett5069]

Great video thank you. Looks like the thermal camera saved you a lot of time chasing your tail. I can imagine with out it you would have been pulling your hair out.

[@MoreFunMakingIt]

I hope I might have got there eventually 😆 But the camera really does help me skip a few traditional steps.

[@8bitkid408]

My favorite computer. Coupled with a 1024? Monitor for 80 column display. CPM FTW. The other was my TI99/4A.

[@griffinretro]

MT DRAM. If it hasn't gone bad yet it will. If I see them in any machine I replace them, they are that prone to failure. In my experience the C128 is fairly reliable for a C= build computer, faults most often occur with DRAM or MOS made logic chips.

[@retroandgaming]

I had the exact same issue with my c128. After replacing the CIA chips it has worked like a charm ever since. But they where a real pain to desolder from the C64 parts board...

[@MoreFunMakingIt]

Fortunately I have a few C64 boards hanging around here with socketed chips :D

[@matchboxcustomsandrestos]

Love the video. This is why you never carry your brick of death by the wires. Or swing it around by the wires. Its ok if you are fighting a burglar or something. LOL. Those MT ram chips are sketchy at best. Most of us start waving a cross over them and start prying. Then call a exorcist to rid the evil they do! LOL. Anyways...you got a new sub from me!

[@MoreFunMakingIt]

Maybe tie two of these together to make a really deadly bolas! Thank you and welcome to the channel!

[@matchboxcustomsandrestos]

@@MoreFunMakingIt Use two 64 bricks for that. That would be even more solid and heavier!

[@RetroComputingReboot]

Great vid. Well done!

[@MoreFunMakingIt]

Thank you! 😁

[@TheBasementChannel]

Great job. My brother traded in our C64 for a 128, I remember getting excited about all the extra power, but then being underwhelmed because our software was all still C64.

[@MoreFunMakingIt]

Yeah, but with 128k! I can imagine that might have been a bit of a let down. Its a shame as the 128 really is a technical marvel. "They" reckon the 128 cost Commodore more to manufacture than the Amiga 500!!!

[@Bergi2000]

Smooth repair! Bravo, keep it up! :-) The C128 is high on your wish list, you fix one for Paul, send it back to him and expect him to sell it on eBay? Kind of backwards/sad.

[@MoreFunMakingIt]

I dont mind. I get to fix and play around with lots of machines I couldnt afford to buy for myself.

[@richardpowell8198]

Another great video again keep them coming 👏👏

[@MoreFunMakingIt]

Cheers Richard! :D

[@RudysRetroIntel]

Excellent video and work! Now you are a 128 expert! Good on you. My first 128 repair, I had to do the same mod to the power supply. I'm not sure if this is a common issue. Thanks for sharing

[@MoreFunMakingIt]

Hey Rudy! Thank you :D Nice to know I got the PSU repair right too

[@RudysRetroIntel]

@More Fun Making It Right is when it's safe and working 🤣

[@purrator]

Those pins on the board for the keyboard connector are an absolute nightmare to connect the test harness to :( They are slightly to small for most DB25 sockets

[@MoreFunMakingIt]

Even the actual keyboard connector is super tight. Can't imagine what tighter that that would be!

[@ANTandTEC]

Good video 👍

[@jaycee1980]

1:22 ugh, ISMET power supply!

[@Breakfast_of_Champions]

What about the X/Y caps in the PSU? Weren't they unsafe ones from the paper cap era?

[@MoreFunMakingIt]

I believe these are the Philips ones and therefore not a problem.

[@CallousCoder]

Dodo 🦤 that’s my nickname has been for most of my life. My godson and goddaughter also call uncle dodo 🦤 My friends and I laugh, we wonder how old they’ll be before they ask if that’s really my name.😂They are no 4 and 2 so I’ll be known as uncle dodo for some more time. And I find it really endearing 😂 And concerning the C128, I bought one a year ago. And it’s a weird little beast. I’ve never owned it in the past and I hardly use the 128 mode but u do really like it.

[@MoreFunMakingIt]

Dodo is a great name for an uncle!

[@leesmithsworkshop]

well done kind sir. I think everyone wants a C128 it's a very desirable computer, but then is it really better than a C64 when you look at the software ?

[@MoreFunMakingIt]

Its bigger! Must be better! 😆

[@leesmithsworkshop]

@@MoreFunMakingIt More RAMZ

[@bwack]

Great video (this is a test comment)

[@MoreFunMakingIt]

YAY!

[@chaoticsystem2211]

This is nice and all. But where's your narrator???

[@MoreFunMakingIt]

He's taking some time off for bad behaviour. Dont fear though, he will be returning in future videos!

[@chaoticsystem2211]

@@MoreFunMakingIt Cheers! I was a bit worried that he accidently touched a hot wire while plugging in a commodore PSU ^^