C64 Breadbin Black Screen Repair ASSY 250407

[@TheDefpom]

A couple of tips for desoldering, after sucking the solder off, wiggle each pin with some tweezers to make sure they are completely free. Another thing which can help on double sided boards (and you definitely aren't keeping the ic) is to use side cutters and cut all the legs off the ic, then desolder one pin at a time.

[@dantootill]

Yep, square-nosed tweezers work well for this. Don't apply any pressure to to the chip until you are absolutely sure the legs are free and you should never lift a trace, pad or (God forbid) the gold through-hole connector.

[@JanBeta]

Thanks! I'm going to pin this comment. Maybe it's helpful to someone and prevents them for ripping a trace like I did... I usually am more careful with desoldering and do the wiggling trick, too. This time I was too sure the chip was loose and failed completely... Did the side cutters trick sometimes but I found it's usually not necessary when using the desoldering gun (and maybe apply some fresh solder/flux).

[@JanBeta]

I usually just use a screwdriver for the wiggling. Have to try it with tweezers next time. I wasn't careful enough in this case and maybe a bit too impatient. :/

[@MultiArrie]

Hi Jan after sucking the solder if a pin stil stuck, heat the legs with a smd/smt reflow station.

[@cbmeeks]

It happens to the best of us. I lifted some traces on a ColecoVision a long time ago and I put it away for the day when I am good enough to repair my mistake. Which I believe I could now but it's too hot to go to my storage building and try to find it. :-D

[@g-wolf9445]

It's amazing how high the failure rate of the power switch is for the Commodore 64. I cleaned one the way you did with isopropyl alcohol and it worked for maybe half an hour. Then I replaced it along with a Kernal ROM and Basic ROM and everything started working. Excellent video. The person who took that Commodore apart to repair it didn't have a clue about what they were doing before you got a hold of it.

[@RMCRetro]

Good work! Those diagnostic carts look extremely useful

[@rscelectrical7091]

RetroManCave : The diagnostic cartridges can be well worth the cost, if you have regular use for them.

[@JanBeta]

Thanks! The cartridges are very useful. Often they only point me in the right direction for further troubleshooting but it's great to have that at least. In this example, the cartridge reported bad RAM because the chip that activates the RAM was faulty so it was not too far off and I found the problem pretty quickly.

[@dantootill]

Kudos for showing what can go wrong when desoldering ICs, nice job on repairing the broken traces. The RAM chips are a pain on some boards, especially the ground pin (the large copper plane draws all the heat out of the iron). I find it helps to brush on a tiny layer of flux paste across the pins before you start, although I can only hope it all gets caught in the desoldering station's filter.

[@JanBeta]

Thanks! I figured that not editing out my fault would help people more than pretending it all went smoothly. ;) I often just add some fresh solder if I can't get a pin out easily. Works most of the times for me. Flux is a good idea, too.

[@RvtvvideoproduktiesNl]

Hi Jan, i bought a c64 250407 rev c, with a black screen issue and no led, i try'd to find the problem starting with the powerswitch, spray it in, leave it and switch now and then. Suddenly there was a start up screen 😀 and its working, at least the start screen and some small tests. Thanks for your hints. Regards Rijk

[@patkelley8293]

I have the same board. It's never been worked on or opened. But did notice the big caps had signs of smoking on the negative side. So I have a cap kit. Only socketed chip is the SID. I was told it worked and the caps smoked when I plugged it in.

[@stanburton6224]

Jan, food for thought in the future. Two things i would suggest were a misstep. First, since you suspected the switch was bad, and the back two pins were not connected, i would not have soldered them, knowing i probably would have to unsolder them again. Secondly, simply temporarily shorting the switch pins out would have told you if the switch was the only issue.

[@TheBurk1989]

I really like these repair videos. I'm thinking one day I might buy a broken breadbin C64 and then try to repair it and hopefully save some money that way. These videos of yours will greatly help with diagnosting faults. I have a C64C already, but I would like to get a breadbin because of the better SID and avoiding the VSP bug that plagues many C models, including mine, which will cause certain games to crash. Great video as usual Jan!

[@JanBeta]

Thanks! It's really rewarding repairing these. Just a great feeling seeing them come back to life after a repair. :) The VSP bug is an interesting one. Are there really games that crash because of that? I had an Aldi C64 back in the day (which has the same short board like the newer C64Cs) and never encountered any difficulties.

[@TheBurk1989]

Yes there are unfortunally. If you remember I asked for help in one of your earlier videos where I had some problems with 2 games constantly crashing on me. Turns out it wasn't a hardware fault, but it was the VSP bug. I ran a VSP test program and it reported back that my computer have massive trouble with VSP scrolling. The games I found out that uses this technique is Creatures and Mayhem in Monsterland. The VSP issue is the reason the games keeps crashing on my computer. I am going to replace the VIC because some sprites in some games has started to render incorrectly in games that used to work great before. I asked at Derbian Games and they think the VIC is the prime suspect for that. If I'm very lucky, swapping out the VIC could also solve the VSP issues, but that's highly unlikely. If that doesn't fix it, there's basically nothing that can be done. :( I have the short board btw.

[@JanBeta]

Oh, okay. Never encountered that bug anywhere. I'll have to read up on that. Sprite problems are very likely to be caused by the VIC so that's a good start anyway. Fingers crossed that fixes the other problems as well!

[@00Skyfox]

Good to know the 74LS257 can be bought from Digikey, and a quick search found lots of 4164 chips on eBay and other sources.

[@andylewis3461]

Thank you for your video. I find that pre-heating the entire PCB with a big old heatgun helps no end when desoldering chips - in other words the desoldering iron has less 'work' to do in getting those presky solder joints hot enough to melt the solder.

[@SledgeFox]

Like watching a detective at work, fascinating, thank you very much!

[@JanBeta]

Oh, thanks! Troubleshooting these old machines feels like detective work at times indeed. But in a good way (especially if you manage to fix it in the end). :)

[@CasualCommodore]

Very nice save! You know, I often think I will skip a bit here and there. But I always end up watching the whole thing, hehe.. Lovely video.

[@JanBeta]

Thanks so much. That's a very nice thing to say actually. :)

[@stanburton6224]

Just to make sure the old chips really were bad, you can use the TL-866 to test them. You can test 74 series logic chips too.

[@ReverendLinc]

Hey Jan, couldn't you test for faulty ram chips by piggy-backing them with new ones before pulling and resocketing?

[@borealis75]

I love these detailed repair videos, great stuff! Hope to see more of this kind. I did buy that same desoldering station because of your recommendation, and it is really a great thing for the price.

[@JanBeta]

Thanks! Yes, the desoldering station is one handy tool. I use it a lot and it still works like a charm. :)

[@TheDefpom]

I suggest soldering the switch pins, for extra mechanical strength, to reduce the chance of it breaking the joints in the other connections

[@maicod]

he did do that

[@MindFlareRetro]

Bravo! Wonderful fix. My initial thought was CIA's or PLA when I saw the garbled screen, but you narrowed it down to those nasty MOS logic ICs quite quickly. Thank goodness for the Dead Test and Diag carts; they save a lot of grief. Great work -- another C64 resuscitated. I can't wait to see what your plans are for the case. Did you ever get any of the replacement case clips from @povvercrazy? Maybe I shouldn't be guessing.

[@JanBeta]

Thank you Mark! Without the dead test cart it could have turned into a lengthy investigation indeed. I want to try different methods on the case to see how well they work. I didn't get the clips yet but I think I should try those, too. Everything else is top secret. ;)

[@AshtonSnapp]

Looked up the ASSY number for my C64 and this popped up in the results. Luckily I already know it works (seller tested and refurbished it, he even put a sticker on the cartridge port), I’m just waiting for the AV cables and PSU to get here as the seller didn’t have any of those to spare.

[@artur3edd]

Nice video, now waiting for the breadbin with similar issues, wander what will it be in my case.

[@JanBeta]

Oh, they are always full of surprises. ;)

[@Dkentflyer]

Excellent video Jan, this one looked quite a challege.

[@JanBeta]

Thank you! Yes, it was one of the more difficult repairs. But I learned from it as always. ;)

[@stripcam]

Desoldering can go wrong quickly with a lot of heat and impatience . I certainly will take my time using my duratool desoldering iron as recently I tried taking off a 44 pin header which was a nightmare as the through holes were tiny as hell and the gun kept clogging up with pins . Madness .

[@JanBeta]

Yeah, desoldering can be very tricky... In this case, my usual impatience strikes back. I should have been more careful. But in the end, maybe showing me messing it up prevents others from doing the same.

[@stripcam]

mate ive destroyed the through-hole pads already with the same iron, i think its probably heat 360 degree c is too much when doing delicate thing perhaps? i'm going to use 320 from now on and try reflow the solder carefully and suck it out with a CLEAN gun, something that makes a big difference imo.

[@Starchface]

Given that the RAM chips are no longer produced, might it be a better strategy to replace the multiplexers first when you see such memory errors? The 74257 is a very popular IC and is still in production so you can consider them "disposable", as opposed to the precious RAM chips.

[@JanBeta]

Might be a good idea for the MOS branded multiplexers at least. Other brands rarely fail (in this context at least) and it’s more likely that the RAM fails in my experience.

[@Starchface]

I see, interesting. You have much more experience with this equipment than I do. I'm learning from you :D and one of the first things I've learned is, when it came to reducing cost, almost everything was on the table at Commodore. I can't say it was a bad approach. They got machines into millions of homes, and in my neck of the woods, the C64 was by far the most popular microcomputer of the '80s. I have fond memories of the ol' breadbin.

[@JanBeta]

Yes, they did pretty well! They tried to produce everything in-house (MOS belonged to Commodore) to cut cost but MOS couldn't do every kind of IC right so some are known to be weak spots. Otherwise the machines are pretty well made for the price. The power supplies are way worse.

[@MultiArrie]

there are still plenty 4164 ram ic's outhere and they cost a tenth of a cia pla or sid IC's.

[@MrTobysDad]

Thanks for another good video, after coming across your channel a couple of weeks ago I decided to try my C64 which I brought a year ago. I bodged a cable up to my tv's start plug and switched it on and got a blank screen. Some of the chips had been socketed (the 2 CIA's the PLA and the big chip next to the PLA) so I removed the CIA's and it improved. I then put the original U2 chip in U1 and it sort of worked but the characters where changing colours. I'm now waiting for a replacement CIA chip, but if there's still a problem with the characters I'll look at the PLA which is getting hot. My case also has all the clips broken off, so I can't wait to see what your fix is, although I don't have access to a 3D printer. Also I'm going to have ago at retrobrighting this weekend as my case is very brown and it speaks of a sunny weekend here in the netherlands.

[@JanBeta]

Thank you for watching. :) The fault you are experiencing really sounds like one of the CIAs is faulty. The PLA gets really hot even if it's functioning normally so hopefully it's just fine. I'll definitely have a go at repairing the case soon. There's different methods I saw on the web and I want to try some time. I don't have access to a 3d printer either but I can order 3d printed parts (or ask some friends to print stuff for me). Good luck with the retrobright (and especially with the weather)! ;)

[@vladeb1104]

It was a nice experience to watch your work.

[@JanBeta]

Thank you! This one was quite stubborn. ;)

[@scottson2]

I have the opposite problem with the power.. I have the 5vDC but I don't have the 9vAC. i just checked the power cable and i get 10vac on pins 6/7 but when i check the inside pins 6 and 7 i only have .2vAC on pin 7. Shouldn't i have 9vAC on both 6 and 7 inside the case? And if its the switch what can i do to fix it/replace it? I have no power coming from VR1 or VR2 on the right most pin....

[@JanBeta]

Is the fuse in the C64 good? It might also be a problem with the power switch, it’s quite common.

[@scottson2]

​@@JanBeta I just checked the fuse and its dead.. Based on the service manual for my board 250407-251137 it's a 250v, 1.5A normal blow fuse.. I just ordered a 5 pack from ace hardware which will arrive in a couple days. Thanks for the advice. Hopefully that fixes it as I did a super cleaning of the case and keyboard/keys and can't wait to try this out with the new svga to hdmi setup.

[@bwack]

Great! Why they used custom chips where 74LS exist. Strange. Where do you buy the precision sockets? The ones I have are bad quality

[@JanBeta]

Thank you! I think they used the MOS chips for cost reasons. Probably spared them a couple of cents per unit. ;) I don't remember where I got the sockets unfortunately. I must have gotten them from eBay quite a while ago. They are good quality but no idea which seller they were from.

[@billwilliams6338]

ok thanks, what RAM/ROM programmer are you use to test RAM and ROM chips? does your programmer test all kinds of TTL families IC chips or just a few TTL families?

[@billwilliams6338]

JAN BETA, How does the c64 diagnostic program know how to test each RAM chip and ROM chip, how does it test each RAM and ROM chip? the diagnostic program must have the address mapping and decoding built in?

[@JanBeta]

It's writing values to RAM and reads them back. If incorrect values are read back, the RAM is faulty. It only tests a relatively small portion of every chip though. I don't know exactly how the ROM checks work but I reckon it reads certain parts and compares them with a little build-in database to determine the ROM version and if it matches.

[@sfoneloki]

Hi, thankyou for your great videos... Can you help me where to find a new power switch? Its a commodore custom power switch? I think not... I'm having trouble looking for it on ebay or aliexpress.

[@JanBeta]

Thank YOU! The power switch is pretty uncommon these days so it's not easy to source. Replacements are available from digikey (sometimes elsewhere). Search for CKN2030-ND.

[@TinyGoliath]

I have this model with a sid 6581 that gets it 12 volts but I get no sound from it what do I do?

[@JanBeta]

Might be a broken SID. They usually break gradually though and start to distort/glitch at first. Check the connections from SID to the output socket and also measure the 5V supply directly on the SID. It needs both voltages to work.

[@kattan2006]

I gave you the thumb up but honestly this video is not your standard!! Either you are tired or not in the mood while making this video!!!!

[@DavePoo2]

22:57 - Sorry Jan, i know this is the Jan Beta from the past who did this, but i was cringing while i watched you prying up that RAM chip with such force, and then you broke the trace! So for anyone in the future watching this. You want to use the de-soldering station like Jan did, but then after that also use a hot air station to heat the pins and then remove the chip using very little force at all. From my experience, i've never been able to get the chip out with the desoldering station alone. Even the smallest amount of solder remaining in the join will hold the chip in and cause the trace to rip if you force it out.

[@llq1999]

ME too, after changing fail sw, i got the screen, but can not figure out which ic fail?

[@wader1710]

Hi me c64g shows me black sreen sometimes. When i use black box with reset it work 100%. What can i check ?

[@Ichinin]

Cool video. In the future it will probably be possible to print IC's as long as someone has the blueprint for it.

[@JanBeta]

That would be awesome for restoring these old machines. Today's programmable logic (FPGAs etc) is pretty close. It's not the same as copying a chip physically, but at least you can copy the functions pretty accurately.

[@maicod]

that beeping sound of fastforwarded desoldering sounds so funny

[@JanBeta]

That's why I didn't put my usual music loop over it. ;)

[@maicod]

;-)

[@vintagekyoshodotcom]

Great job! As always you resurrected another 64 from death!

[@JanBeta]

Thanks! :)

[@azariayehezkel9064]

What a most reliable vic-II? 6557/8562/8564 for ntsc . 6569/8565/8566 for pal. I want buy one pal and one ntsc

[@SilverGreen93]

Is that U8 chip with the "beta" logo (at 23:34) the original one that came with the C64? That chip is produced at IPRS Baneasa in Bucharest, Romania :) I'm proud to see it in a C64!

[@JanBeta]

Oh, interesting! I just had another look at the PCB and it seems like the chip was in there originally. No traces of resoldering to be seen. Thanks for that info! Commodore was famous for using whatever parts they could get their hands on so it makes perfect sense. :)

[@refractionpcsx2]

Nice repair job! Some good diagnostics :) Reminds me I need to repair my C64C still, it has a chip which is burning up, I think it's either a RAM or Multiplexer chip, just been lazy in getting replacements and doing it lol

[@JanBeta]

Thanks! If its burning, it's most likely RAM. The logic dies silently in most cases I encountered. ;) Hope you manage to fix it soon.

[@refractionpcsx2]

Probably is, just couldn't remember where it was on the board or the part number, it's been a while since i burnt my finger on it :') But yes, probably was a ram chip, hopefully replacing that will solve the black screen issue it has!

[@hanswurst3811]

@4:09 why are these circuit lines so loose from the board? does they still work ? is it normal ?

[@JanBeta]

That's from factory. The 9VAC are bodged from the power jack to the user port, if I remember correctly. They would have to put thick traces on the board otherwise so I guess they chose the easier solution of just running a cable...

[@aphexteknol]

Nice repair and all, but where can I get myself a sweet LIPS brand monitor like yours Jan Beta? :)

[@JanBeta]

It's a very limited edition! Really rare, ;)

[@shiloh6809]

thanks for another great video. it helps me moving forward in my repair process. the mos 74ls257 were both bad in my case. Quick question: I see that you have a nice C64 saver power cable. where can I buy one of those?

[@JanBeta]

Thanks! Always glad to help. :) The saver I'm using is the 64saver by Hans (bwack). You can contact him via his KZbin kzbin.info or via Twitter @bwack77 and ask for prices/shipping etc. I don't know if he has any left at the moment, though. There was quite some demand recently.

[@recepunal7993]

Congrat jan, you did again.

[@JanBeta]

Thanks! It always feels good to resurrect a C64. :)

[@esshahn]

good work as always Jan, thanks for sharing

[@JanBeta]

Thanks! :)

[@robbyxp1]

Great video Jan. Enjoyed it a lot.

[@JanBeta]

Thank you!

[@Dave7160]

Hello Jan Beta my commodore 64 also has a black screen video chips are good but the rams bad when I touch it it's like super hot to the touch is it easy to solider on sockets then put the new chips in or not? also Does it matter which chips I get or not because there's many different ram chips for the Commodore 64? and Due to the fact my C64 is brand new in the box in mint condition by me replacing the chips would that affect it's value in the future or not in terms of originality?

[@JanBeta]

If you have never before desoldered ICs, I suggest you practice on some scrap boards before you tackle the C64. It‘s a pretty non-trivial task and you can easily break traces if you are not careful. As for the value, I think it’s more valuable if it works but I don’t consider myself a collector but a user so I can’t speak for everybody. There’s a couple of different RAM chips used in different C64 revisions. Which kind you need depends on how many RAM chips you have on the board.

[@Dave7160]

@@JanBeta Hello thank you for writing back to me so promptly I appreciate that, my board is from 1982 if that helps with identifying ram chips?

[@JanBeta]

Yes, so you have 8 RAM chips. You need 4164 (or compatible) RAM. The brand does not matter. Ideally, you choose the same RAM speed as the other chips (usually the last 2-digit number printed on the ICs eg -12 or -15). Choosing the same speed is not strictly necessary but is recommended especially on older boards like yours.

[@Dave7160]

@@JanBeta Hello thank you very much for telling me Honestly to me you sound like an expert in Commodore computers and I mean that from the bottom of my heart, to find someone who knows about vintage computers is one thing to find someone who would be willing to help with certain Q and A's is totally different, which is better getting them socketed in or soldiered onto the board? and there are some chips on eBay 8 of them with socket sets from Bulgaria would the European versions be different from Canadian versions?

[@JanBeta]

The 4164 ICs are compatible with each other. Commodore themselves used a wide variety of different brands. I recommend putting a socket in. It’s easier to solder and you can replace the chip again in case it is faulty.

[@fortnitegod2647]

Great vid jan. I would have changed the mos chips first. But you can never tell🤔🙋

[@JanBeta]

Thanks! The dead test cart blinking differently sometimes should have pointed me in the right direction I guess ;)

[@DappieKS80]

Just curious, what is the problem with the donor board?

[@JanBeta]

+DappieKS80 It has a variety of problems. Some broken traces on RAM, broken RAM, I suspect broken CIA. I tried repairing it long ago (with less skills) and gave up on it. Now it saves other boards.

[@drewpaschal9294]

Awesome vid Jan. Thank you!

[@gile849]

Yeeees! +1 C64 back to life :)

[@stephenbruce8320]

Nice job. Fear the traces on the old boards sometimes they require more TLC than your significant other besides computers are your best friend when they act up they can be reset unlike ones significant other which do not come with a reset button (Ahem). Don't be too hard on MOS Chips hey many fail but many are 30 yrs and still functional. The board I am working on right now is also a 250407 its a waiting game for me that is waiting for parts to arrive and then I need to wait for when I am off from work.

[@JanBeta]

Thanks! I was a bit too impatient with the traces really. It could surely have been avoided. But on the other hand I think it's okay to show how easy a trace is broken so maybe I'll spare some viewer somewhere the trouble of trying out themselves. ;)

[@JustWasted3HoursHere]

It's a shame that so many of the parts that these old computers used are getting harder and harder to come by. Good thing we have modern alternatives to these old systems like the Raspberry Pi (via emulation). I think there's even an FPGA-based system that can emulate just about anything you can think of, not with software but with actual programmable hardware. Still nice to run stuff on an original system, though. I think I still have my breadbox 64 around here somewhere...

[@JanBeta]

Yeah, emulation is getting better. There's an interesting FPGA version of the C64 coming up called the 64 Ultimate. Original form factor so it can be put in an original case even. I still prefer the original hardware for that warm nostalgic feeling though. ;)

[@JustWasted3HoursHere]

Thanks for the info on the Ultimate 64. I see that they are only going to build 200 units? That's a shame. Or maybe I read that wrong. I like that it supports the cartridge port and the datasette (but no user port, which is not really a big deal to be honest). Yeah, I agree with you on playing games and such on the original hardware is the best, but one really nice advantage of emulation is that there are no caps or chips to "go bad". Of course, the host hardware can run into those problems... ;) Here's the info on the board for anyone else who's interested: 1541ultimate.net/content/index.php?option=com_content&view=article&id=74

[@JanBeta]

I think Gideon says that he needs to have at least 200 units produced for the price to be reasonably low. He also makes the 1541 Ultimate which is continuously produced in small batches. I think it's going to be the same with the 64 which is great. Speaking of host hardware... I'd really like to see if most of our modern PCs will still work in 30 years from now. Probably not. ;)

[@psplaystation1]

can anyone help please, my 64 types characters by itself even with 2 known good cia chips fitted and keyboard removed

[@cbmeeks]

Awesome video as usual! Plus, I noticed the dead test cart has the "proper" spelling of "color". LOL!! :-D

[@JanBeta]

Thanks! Lol about the spelling... Now I wonder if there are localized versions of the Commodore diagnostics carts or if I should make some. ;)

[@rubusroo68]

why does it need the 10v ac? is it 50hz?

[@JanBeta]

It's the 50Hz PAL model, yes. The 9V AC (10V on my power supply) are used for the user port, some VIC timing and to get the internal power rails 12V, 9V, 5V DC that power various things.

[@WehofnerLP]

Super Video, ich hab wieder was gelernt :-)

[@JustWasted3HoursHere]

We should go a little easier on Commodore (and other 'golden age' computer manufacturers) for using chips that can go bad: They were not thinking that people might be using their systems 30 years later! To be honest, I'd say that MOST of those old systems - if they were at least relatively well-cared for - are still working not too bad. My 1987 Amiga still works just fine, for example...

[@JanBeta]

They were definitely build well especially considering the price they where sold back in the day. The MOS logic chips commonly failed even back when they were new. MOS just couldn't do them right for some reason (whereas many other ICs they did great on). Commodore went on to use other manufacturers in later board revisions. Amigas and later C64 revisions are pretty sturdy in general I think. Except maybe the Amiga models with batteries that leak and destroy traces on the boards over the years.

[@JustWasted3HoursHere]

Yeah, I wish those old computers had put the CMOS battery (for example) on its own board, away from the rest of the computer. So many classic computer repair videos that I've seen run into exactly that same problem. And leakage can be REALLY hard to fix! Sometimes impossible, depending on how long it's been leaking.

[@dmode79]

why you cover the brand of the screen?

[@JanBeta]

It's just a joke, nothing more. I kind of like to play with words. ;)

[@alexboehm7171]

what is the chance that three independent components fail?????

[@JanBeta]

It's pretty unlikely unless one fault causes the other. In C64s, there's often faults in more than one IC if the power supply has failed previously. My guess is that similar issues may occur caused by a wonky power switch (voltage spikes? arching?).

[@wimwiddershins]

Very nice video Jan. Thanks for they great videos. Though I saw you dab soldering at ~31:00. :)

[@JanBeta]

Thanks for commenting and watching my stuff. :) The dab soldering was just to hold the socket in place for easier handling. I redid everything nicely afterwards.

[@estebanquito545]

excellent fix but heat not more than 3 seconds, use flux

[@xxTeamFearLessxx1]

Dieses Auslaufmodell hat doch seine Popularität nur dadurch zu verdanken weil es mehr rem hat und Commodore das Ding verschenkt hat wenn man mit einem günstigeren Heimcomputer um die Ecke kam. Der C 16 ist aber Leistungsfähiger.

[@staticfanatic]

Jan: I've taken a look and I think there is a good chance it might be this thing. Me: Hmm, yes, very good. *Still ⅔ of the video left* Me: No you idiot, of course it isn't that.

[@JanBeta]

Haha, makes me think I would like to watch the end of my own videos before I start troubleshooting sometimes. This one was a tough one with multiple faults. Usually it's just one most of the times.

[@Tom2404]

I just killed a C64. :( It did't really work before, but now it is definitly dead. It didn't take any inputs or have sound (tried that with a cardridge game). I took the SID chip out of the socket, cleaned all of the contacts and put it back in. I pluged it in but only partly assembled. First it worked, I had sound again and I was really happy. But then I wanted to turn it back off to put it back together, but there were sparks coming from the board when I tried to plug the power cable out. Then I realized that the cardboard that originally was in the C64 I put the board on has a piece of metal on it, where it was attached. And this piece of shit touched the board when I tried to turn it off. First it was a wierd pattern on the screen. But after I finally got it disconnected from the power, and then plugged it back again it only shows a white line on a black screen. But the worst thing is, that I probably killed a working VIC and a working SID chip. Now I have to write it somewhere because I really still can't belive that I really did something that stupid. 😢😭😭😭😭😭 Is there any chance the that at least the SID chip still works?

[@JanBeta]

Oh, that's sad. Poor little C64. On the positive side, you at least made an effort to bring a non-functioning machine back to life. Chances are the SID still works, they can take quite some voltage (at least for a short time) I found. I only managed to kill one SID yet and that was not in circuit but by electrostatical discharge. :/ The black screen could be caused by a number of things. Usually it's the RAM that blows up first on the old boards. I wouldn't worry too much about the VIC if you see a white line (on the left side of the screen?).

[@Tom2404]

Jan Beta Yes, the line is on the left side. And it is one of the later boards, it is an Assy 250469 rev.4. But I don't have tools to to test all of the ICs, so I don't have any idea which ones are still working.

[@Nelson68k]

Cool wieder einer mehr.

[@JanBeta]

Danke! Wenn ich könnte, würde ich glaube ich versuchen, alle kaputten 64er wieder zum Leben zu erwecken. Vermutlich werden leider immer noch viele entsorgt.

[@thedutchretrogamer]

hey ive got the same postcard from amigastore :)

[@JanBeta]

Got it as a donation very recently. I absolutely love it. :)

[@thedutchretrogamer]

yeah i love it to on the screen you see cannon fodor and the toy soldiers on the table

[@johandenhertog6878]

I liked the 250425 and is more reliable than the 250407.

[@JanBeta]

Yes, they definitely refined the design. My favorite is the 250466 (I don't own unfortunately) which is another step of refinement before Commodore introduced the cost reduced short boards.

[@PhrontDoor]

When I remove chips, I tend to first clip the pins to protect the board.

[@JanBeta]

That's probably a good idea. I sometimes do that, too, at least on chips I am absolutely convinced are broken.

[@peter486]

im gona admit someting c 64 was better than spectrum.

[@e5frog]

Retrotech is selling proper new and compatible power switches. www.demand.nu/retrotech/r8017l-r21.html Goldplated sockets make the chip pins oxidize faster, ideally they should be the same material.

[@JanBeta]

Oh, cool! Thanks for the link. I knew there were replacements for sale somewhere but couldn't find them anymore when I looked for them. Ah, never thought of the oxidization. Makes sense.

[@hanswurst3811]

YEY !!! DM KLOPAPIER !!!!!

[@JanBeta]

Well spotted. ;)

[@petti78]

You are manhandling that board into oblivion... bashing and banging, droping the fluke on it all the time... you are gonna have a lot more to repair with that kind of abuse. I had a faulty power switch on my 64 too, the contacts were totally black inside. It's pretty easy to disassemble, clean and reassemble the switch.

[@JanBeta]

I think these boards can take some bashing and banging (although you are right of course... I should be a bit more careful)... I will disassemble the power switch and have a look inside. I'll at least have another spare one if I get it working again. Thanks for the tip!

[@onehappynegro]

i did the same with my main c64 unit for years, no problems. however today i'm much more gentle.

[@petti78]

I've been watching all of RetroGameModz videos lately and his perfectionist approach really rubs on a bit :-)

[@JanBeta]

Haha, that explains a lot. I'm probably never going to reach his level of perfection. ;)

[@psyolent.]

LOL @ severely dead. my C64C was severely dead as well. BSOD --> Black Screen of Death due to dead CIAs

[@JanBeta]

Oh yeah, the CIAs fail often and cause the BSOD. ;)

[@BitBanger]

Circuit board butcher......

[@michaellowery1559]

Side cutters! that's all im going to say! Jans already feeling guilty!

[@8bitdreams217]

why there is a toilet paper on the bench? R u goin to sh*t on the C64? lol

[@JanBeta]

Haha, no. I'd never do that to a lovely C64! I just ran out of better tissue paper.

[@discoHR]

Toilet paper on the bench means thermal paste is nearby. :)