Well, it's nice to see that C64 finally fixed. I had given up, and after watching that video, i'm sure i'd have never gotten it fixed on my own, so thanks! I have a Zener diode to fix that cassette port from a (would you believe) worse parts board. Also another SID chip (I might have put the flaky one i had in there because I didn't want to risk a good one in that board). Just need to track down a PLA chip (or PLAnkton).

@LeftoverBeefcake

4 жыл бұрын

Go for the PLAnkton! I have one in my original C64 from '83 and one in my SX-64 and they work wonderfully, and run very cool. I would never again want to use an original-type PLA chip when they are basically time bombs.

@DrTofu83

4 жыл бұрын

Agreed. A PLAnkton runs colder, doesn't die on you and has the potential to outlast the C64 board :)

@brianv2871

4 жыл бұрын

Adrian has something he's testing that might be a cheap alternative to pla's or Plankton's so I'm waiting to see how that goes.

@DrTofu83

4 жыл бұрын

@@brianv2871 I'll be waiting for the magic Bell Icon too. I'm really interested of anything able to replace a PLA

@alteregos8949

4 жыл бұрын

@Jayson Cowan at this stage of the game we are well past the early on point that’s for sure. 37 years and still locating working ones is getting harder and harder these days.

This is one of those videos where about half way into it I wonder to myself: "Why on Earth am I watching this, I have never owned or will ever repair a Commodore 64 computer." Then it dawns on me, just like when I watched a guy construct a scarf joint on a large wooden beam....there is something very satisfying about watching true masters work at something, and continue to work on it until it is done. Okay now on to watch some glass blowing expert. LOL.

@PeterJaquesMusic

4 жыл бұрын

same, though i did used to own a c64 (even into college!). i would never repair one, but it was just super engaging to watch the mystery unfold

@thomaswilson9780

4 жыл бұрын

I actually could have written this comment!!

@psour33

4 жыл бұрын

I strongly agree :)

@kaczan3

4 жыл бұрын

I'd recommend to you channels about renovating old metal tools and knives.

@martynlewis5901

4 жыл бұрын

I work on domestic gas equipment (boilers, fires & cookers etc) in the uk. I’ve always been fascinated/interested in computing and owned a ZX Spectrum (amongst others) back in the day. I would love to get into this sort of thing but wouldn’t know where to start. I frequently use a multimeter for working on boilers but this is a whole different skill set.

"total novice" is being way too hard on yourself - this is some 'level 7 - chip ninja' stuff you are pulling off. very impressive and well done for your tenacity in getting it done.

@SpaceButler010

4 жыл бұрын

Anyone who can repair that thing is not a total novice. This was a ton of work that needed know-how, investigation and skill.

@StrapMerf

4 жыл бұрын

experience trumps training anyday.. a few minor things would have helped with formal training, and knowledge of failure modes, but they would have saved a few minutes at most.. training makes gaining experience slightly less painful.

@Mike3DPro

4 жыл бұрын

Novice?! you have scopes laying around AND a bald head! That pretty much makes you god mode by itself 😎

@metesev

4 жыл бұрын

Someone having an oscilloscope and using it to test the chips ain't a novice :) Novice is someone like me only using the solder iron or doing some point-to-point tests :)

@jdryyz

4 жыл бұрын

Have to agree. You're definitely above the Novice stage. More like Advanced.

Wow, I've just sat here for 40minutes not knowing what the hell was going on,but utterly transfixed😃

@RichardCatto

4 жыл бұрын

yeah, me too. I just wanted to see if he could get it working again. pretty amazing to watch actually.

@normanbates19

4 жыл бұрын

Hahahaha me too! I love watching electronics repair videos, but have absolutely no bloody idea what it going on

@MrAndroidData

4 жыл бұрын

same here

@VamosConLaPeli

4 жыл бұрын

Guys, there are good electronics tutorials on the web, you might want to check out www.electronics-tutorials.ws/ or simply throw into duckduckgo.com the words "electronics tutorials". And you might also want to get familiar with the Arduino IDE (implies also learning C++), which allows to program many different microcontroller boards of different architectures (AVR [e.g. ProMini or ProMicro], ARM [e.g. STM32F103C8T6], or some wi-fi connected ones like NodeMCU ESP8266...). You might also decide to put that together with what you learnt in the electronics tutorials and design some extra hardware to use with your microcontroller board, you'll have to test it on protoboards and then maybe use KiCAD to make a PCB (you might buy a budget oscilloscope like Hantek DSO5102P and a KKmoon dual channel signal generator, both great value for the money... or maybe something more expensive). I've come to watch this one because I have been a C64er for quite some years, also doing some assembly coding on it :D and of course I remember some great whole-summer-night videogame sessions with my brother, we are now living in different continents.

@themetalmicky

4 жыл бұрын

me too, im bamboozled

If someone says, "it's fine" TEST it anyway.

@Baerchenization

4 жыл бұрын

My mother said the radio of their stereo system stopped working. So I Ebay-ed them a replacement. When I finally went over to my parents' place this Xmas, it turned out the radio was perfectly fine and instead it was the amplifier that had stopped working :) So yeah, never listen to other peoples' diagnosis ! Her comment: she calls the entire stereo system " the radio". Cheers, mum :)

@MickeyMousePark

4 жыл бұрын

@@Baerchenization I worked in the computer hardware repair industry in the 1980's the first lesson they taught us was: Listen very carefully to what the customer thinks the problem is and what they think will fix it..after the customer leaves ignore everything they just told you... On side note our troubleshooting skills in hardware repair was make sure you have good power to the board then start at the CPU checking all input and output signals and work from there..we were lucky our schematics had OScope images of all pins of all logic chips on the board... 10 years later i worked at Microsoft internal IT (software) and first thing they taught us was: Listen very carefully to what the customer (these were MS employees) thinks the problem is and what they think will fix it..after the customer leaves ignore everything they just told you...

@someguystudios23

3 жыл бұрын

My dad is an electrician and he always says, "if someone says the circuit is off, test the circuit. ALWAYS TEST THE CIRCUIT."

@codprocamp4690

3 жыл бұрын

Especially when she doesn't bring condoms

It's fantastic to see how much love these old machines still get almost 40 years later. I just found my original C64 again after "losing" it for decades.. :-)

wow this takes me back, back in the late 80's i used to fix these for a living, a repair company in Monmouth UK called Mills, cant remember having a cool diagnostic cartridge, but i can remember on blank screen faults removing all the top row roms and chips along side of it and using the game Jupiter Lander cartridge game, this game didnt need any of the top row installed and if it worked you knew the fault lay in the chips you had taken out, also piggy backing ram chips, sometimes you could find a duff ram chip by putting a new chip on top of the old one, (just squeezed on top), All this and you didnt need good eyes to work, now I am replacing tiny SMD stuff which i need a mag lamp, Nice work again mate, took me back 30 years with that video

This is better than watching a TV drama - so many unforeseen twists and turns as the narrative unfolds. Puzzle logic is indeed fascinating.

KZread; "Yo, you like electronic diagnostics and repairs?" Me: "Well, kinda." KZread: "Then just look at this, yo!" Was not disappointed.

Personally, I don't see all that many flubs with your repair. It takes a while to develop good practices for troubleshooting and different people use slightly different methods. You're doing just fine.

@TheBananaPlug

4 жыл бұрын

Agreed, no sure fire 'one best way', all repair guys I have known approach problems from different angles/perspectives.

@azzajohnson2123

4 жыл бұрын

We all learn from adrians learnings and that’s why we all find this so interesting to watch. We have all been there when troubleshooting.

@Spazilton1

4 жыл бұрын

From someone who has worked in Electronics repair for 20+ years in the private sector and the US Navy, your methods are just fine.

@ahndeux

4 жыл бұрын

I saw one huge flub. He should have replaced that last botched wire job at 14:22. He fixed all the other wires and left one raggedy yellow wire. I was cringing when he left it on.

I am an electronics engineer and I think your troubleshooting was just fine. I liked that you used the scope. I am not sure I would have done as well as you. You're very experienced in debugging c64 hardware.

41mins of pure joy of fault diagnosis.

I have two solid years of electronics training and over 30 years of experience, and know very little about the C-64 inter workings, I own two, and used to program them in Commodore basic. You did an awesome job of troubleshooting the board, and had real tenacity in diagnosing each and every problem. You have better patience than I do. Very well done repair and video. I learned a lot about the C-64 watching your video. Thanks!!

calls himself a complete novice, already has much better test equipment than what I'm dealing with... damn

@jeromeygreen4788

4 жыл бұрын

I feel this in my soul

@stifledvoice

4 жыл бұрын

I got a free multimeter from Harbor Freight and barely enough smarts to follow a diagram to wire an arduino to a breadboard, so this guy is lightyears ahead

Hmm, I only have a tip for you, when dealing with bad sockets and chips, cut the legs of that bad socket or chip, then use a desoldering iron vacuum pump. Lets you get rid of each individual leg of the socket or chip without putting much stress on the pad and trace. Just a tip, not a must.

The 113 thumbs down were the previous owners of that CPU board 😂😂😂

I did not realize that "Total Novice" equaled Jedi Master electrical/digital Tech!!! Amazing sir! I have worked in computer software & hardware for 30 years. I found this very relaxing & appreciated your troubleshooting skills! Awesome job in your electrical trouble shooting!! Big LIKE & new Subscriber!

41 minutes just fly when you are watching something fun. Besides that why not make a tutorial for testing different components using different tools (multi meter. oscilloscope, probe etc...) I prefer it coming from a non technical person as my self then from an electronics engineer. Thanks and happy holidays.

@leandrotami

4 жыл бұрын

I didn't realize that the video was that long!

@5Breaker

4 жыл бұрын

*instant realisation* Wait what? That was 41 Minutes?

"piece of crap socket" - **looks nervously at the sockets I've installed in my PET**

@raven4k998

4 жыл бұрын

heres a pat on the back it'll be fine my brother it'll be fine don't worry

@hullinstruments

4 жыл бұрын

AUGAT brand sockets my man!!! They are the best! Usually $5-$15 each but if you watch eBay you can get some deals. I just bought a lot of 20 beautiful gold plated brand new in the package AUGAT sockets for $7 shipped! There a special type, and I could flip those bad boys for $15 each but I’ll hold onto them! I love collecting vintage IC and transistor sockets. There are some really beautiful examples out there that bring crazy money.

@sivalley

4 жыл бұрын

Can't blame yourself if you don't know better!

@jeromeygreen4788

4 жыл бұрын

Can't be that bad in the grand scheme of things, I fix cars and motorcycles as a hobby and the amount of dirt cheap, questionable components that I've used on them with no issues is amazing. If you can convince it to work where it's supposed to the majority of the time it just works, no matter how jankey it is.

@Calphool222

4 жыл бұрын

Some people say double leaf sockets, but I say machined pin is the way to go. I've used thousands of them, and *never* had a problem with machined pin sockets. Double leaf sockets aren't *terrible*, but I've had a few get crusty and fail. Single leaf sockets are the devil and should never have even been imagined.

I loved how in-depth you went for all the little details, and the throughout process of trying everything out. Excellent!

I really like your style in progressing with the diagnostics and I'm glad there's still good care for those hardware gems!

Thank you Adrian for bringing another C64 back to life. Thanks also for taking the time to make these videos for everyone to enjoy. Merry Christmas to you and may 2020 see more repair and other videos from you. Steve.

KZread: Do you want to watch this? Me: ...maybe? Very thorough diagnostic and repair. And now I forgot what I came to KZread for, but feel compelled to go get some C64's and fix them! Nice work!

This was the most awesome repair video I have ever watched. You are amazing having not given up. I'm sure you felt good after seeing that running again. Thanks for sharing.

Great work Adrian. I have run into lots of issues with C64's over the years. It is great to see somebody working on them, troubleshooting them and giving useful tips. This information will be no doubt useful to somebody either now or in the future.

I grew up fixing video games for arcades as a business in the early 80's. All professional arcade machines were designed and built like this. I developed the exact same skills you used to fix this on my own so you are spot on with your troubleshooting and diagnostics approach !

Great video! I usually watch random electronics repair videos late at night so I can fall asleep but I had to pause yours and find another one to watch last night because it was so interesting :) I watched it today and subscribed.

What a great video. Its good to see people taking an active part in making sure these computers still survive and work. Merry Christmas!

I very much enjoyed watching your troubleshooting process. Things are complicated when there are compound problems and a lot of people would quit in frustration rather than break it down into ever smaller problems to fix. Great work!

"Look How They Massacred My Boy" Good job on reviving it.

I can't believe I watched the entire video. I found it fascinating and really informative. Great job!

Hi Adrian, I am a former owner of C64. I used it to create my college papers while I was attending the University of Guam in the 80s. It ran fine until the monitor was broken and I did not have your channel back then to learn how to fix it, so I threw it away all together. Watching your video took me back to thirty-eight years ago. Thanks.

good on you for having a go and sharing you adventures in electronics

You may go around things differently, but you're my favorite KZread channel. Folks like you, LGR and the 8 Bit Guy are the best. Merry Christmas and Happy New Year to you.

Very complex array of problems. Incredible how you didn't give up and went step by step fixing it. Taught me a lesson.

Excellent repair and troubleshooting. Thanks for taking the time to share the journey!

My gosh you were determined to get that fixed. I think my patience would have given out quite awhile in to the project and I would have declared it a parts machine. Good job!

Time for a backup solder station. I deal with removing IC’s and have used your hot air method. Lifted/ripped traces will test patience. Enjoyed this video as it covered several Troubleshooting techniques.

Yours is an excellent systematic approach to repair and trouble shooting. Well done, sir.

you just did a great Job on that C64 Board , I've never saw a Tech doing such a repair like the one you did, congratulations.

Gotta love working on a board that someone has messed with and pulled up traces. Having a good desoldering iron with the proper tip is essential to prevent trace damage. For most of my vintage boards, I use the Hakko A1002 nozzle with the 0.8mm diameter. And it's also important to maintain the pump and seals so you get enough vacuum.

@shawbros

4 жыл бұрын

The best scenarios are when you know who caused the problem(s), and after fixing the problems, you can explain them all to the person, so they realize their incompetence.

This was easily the best video you have ever made 10/10

This is the best C64 repair video I've ever seen. While so many just seem to document a PLA swap, here I think you hit (and remedied) the majority of issues I've found with C64 motherboards in one go.

Your patience and perseverance are becoming legendary . Love watching your vids

This was like watching a very gripping 41 minute mystery show. Great work!

"This socket is a piece of crap!" - Yeah.. as soon as you pulled that chip, I said the same thing in my head.. I hate those sockets too!

@throttlebottle5906

4 жыл бұрын

they cause more issues than they fix, I've had to remove many from all sorts of equipment a bad one is 8 pin op-amps in amplifier early stages, had them go intermittent and drive output stages to near full DC rail voltage and cook speaker coils!

@SteveJones172pilot

4 жыл бұрын

@@throttlebottle5906 Interesting! I hadn't considered a scenario where a failure like that could cascade to another failure but that's a good thing to remember! I generally run into them on old vintage arcade machines (PacMan and Williams pinball machine boards, specifically..) where it may cause something not to work, but I've never seen it break something else!!!

@mikeh4775

4 жыл бұрын

I own a Donkey Kong arcade machine and have had issues with IC sockets as well

Wow! What a monumental effort to fix that board!! Awesome that you completed it! Congrats!!

This one was a tough cookie! Great repair and video. Love what you do and how you do it.

I have never cared for Commodores, growing up at the tail end of that era, but this video was very interesting! Good job getting it working right.

novice, are joking your the type of guy whose method gets written into tech journals. very good work

Oh man, I'm finally starting to feel more confident to start approaching circuit troubleshooting using schematics now, especially since now you've shown results of many mistakes caused by previous repair attempts. Going for round-hole sockets is a nice tip too!

I had a lot of fun watching this video. It brought back lots of memories of the C64. Thank you for sharing!

jesus just saw it was 41 mins long but felt like 10 mins wow nice work

It is interesting to see that the test harness, whilst very useful, can only go so far. Then you are back to reading the schematics. Thank you for reminding me of the important lesson of looking at the board first for 1) Broken traces 2) Bad/broken/dry solder joints. It is just so easy to jump in and start de-soldering components.

@stefanocrespi5424

4 жыл бұрын

@@adriansdigitalbasement but it wouldn't have given us a full 41 minutes long good entertaining!

Doesn't matter how experienced one is, electronics repair is ALWAYS a learning experience! Thanks for this, Adrian, great vid as always!

Nice job!. I have the utmost respect for your patience and perseverance Adrian, you inspire me to try and repair some of my old C64's as well! Keep up with making these excellent videos!

I ended up watching for the whole length waiting with baited breath each time you switched the power on.

@23:42 "So to recap..." Me: "Oh, you're going to replace all the capacitors next???"

@raygud

4 жыл бұрын

a lot of leaking capacitors there...

I enjoyed watching you struggle your way through the repair, simply because someone had butchered the motherboard. I particularly liked your logical approach, and your perseverance. It all paid off..

That was a very thorough look into diagnosing the computer. Your thought process on tackling something that seems daunting to the novice actually became easy to follow. Thank you!

My Dad bought his C64 when I was about 4 years old. I'm 40 now. He still has it and it still works. It's never needed serviced or repaired.

@adamw.8579

4 жыл бұрын

These was good times when "programmed wearing" was unknown term. Proper engineering and equipment was made for years (sometimes for decades).

I was out of ideas before you were 5 minutes in.

Awesome, liked that you showed all the trouble shooting steps you have done. Keep it up!

That pictorial fault guide page is very handy. I had a fault that I got published on there, the broken trace fault at the bottom of the page. Nice work on fixing this machine! It is so satisfying to finally get to the bottom of a problem and get the beautiful blue screen of life on a C64.

This video was amazing! Your tenacity during the troubleshooting process was very impressive. If you are at all interested in attempting to repair a faulty Atari 1040 STf please let me know. I've had the machine for about 1 year and can't get video to display. Big fan of your videos!

@brianv2871

4 жыл бұрын

Have you picked up the Diagnostic cartridge? I think BEST sells one, which is where i got mine. I ended up having to just pick up another 1040STF and do chip swapping.. once you figure out the chip, you can just resell the 2nd computer on ebay. With my 520ST that couldn't display video, I ended up replacing the C025914-38A chip. You're using the original monitor, I assume?

@abar1120

4 жыл бұрын

@@brianv2871 Thank you for the advice. I don't have the diag cart. I always figured the issue would be the Shifter chip or the glue chip. I actually have a working Atari 520 STf but have always been weary to swap the chips as they don't look identical to what I see on the 1040STf and didn't want to risk damaging components from my working system to test the 1040. I don't have the original monitor but do own monochrome and color VGA cables that works with an Acer monitor capable of the 15khz refresh rate. This of course has been tested on the on the 520. Thanks for the advice!

@brianv2871

4 жыл бұрын

so my two boards, the chips were slightly different as well, but googling i determined the parts were just newer revisions (something like 30 vs 30a). But yeah, i guess do what your comfortable with, but the 520stf and 1040stf were essentially the same machine but with more ram. in fact, my 520stfm had empty slots that could be filled to make it a 1040. I never bothered with that since i used to have a ram module that stopped working and might just get or make another one at some point. I only asked about the monitor because I've not had luck using the special cables (like composite, or the scart cables) on non modulated ataris, but i assume if your setup works on a non modulated Atari then you're good there. Anyway, don't think Adrian could really help on this, because even if he could diagnose the issue, he'd need parts to swap in, and he doesn't really have spare parts for them like he does commodore. If i recall, he just has the STE, which has different chips.

@markwanklyn4195

4 жыл бұрын

@@abar1120 no video output is not necessarily a video fault - my STe had no video output and it turned out it was the reset circuit that was at fault -bad output on the 555 timer chip was causing the reset line not to be toggled correctly on power up

@PCBoardRepair

4 жыл бұрын

@@brianv2871 chip swapping is just guessing

Thank you for saving my childhood. Imagine if these were ROHS, then there would be no way of getting these to be alive again. I stopped putting my failures in videos because I feel KZread saw them as demonetization issues. Mind you they never tell you why your video is demonetized. Funny how some people don't say the 'L' in soldered. Maybe I'm saying it wrong.

@SonicBoone56

Жыл бұрын

We Americans tend to drop the l in soldering.

Very fun video! Was intrigued by the compounding problems and ur resolutions. Great stuff!

That was awesome. You did great work. I like that you didn't just get it working, you cleaned it up and fixed it right. Very Nice! I'm really regretting tossing my C64 a few decades ago.

It was pretty common for the RAM chips to fail. I remember doing lots of those back when I worked for a school board that had hundreds of C-64s

I think someone had that character ROM issue when they invented the Ancient script for Stargate.

Quality Content! Thanks for taking us on this adventure with you ^~^

Great repair Adrian. Another C64 back in operation. Though this is one of your longer videos, it didn't feel like it, it flew by. I'm also enjoying your improved audio and video, nice job 👍

Wow - that's what I call a labour of love! How many hours went in to that repair?

@martinkuliza

4 жыл бұрын

@@adriansdigitalbasement that's true filming it and having to explain shit all the time , really slows down the process. i reckon you probably took an hour or two realistically if you didn't have to video or explain stuff me and a friend recently repaired a COMMODORE P.E.T. initially had display but it was all Garble at the end of the day ....... Character ROM and buffer had to be replaced all fixed now in total... Probably around 1.5 to 2 hours and maybe 5 cups of coffee LOL but.. it was fun

Enjoyed this immensely. I would attribute your aversion to novice status to the Dunning-Kruger effect. Bookmarked The Pictorial C64 Fault Guide. Hopefully it will help with my C64 character ROM issue.

@leandrotami

4 жыл бұрын

Don't you mean the imposter syndrome? This is a case of a person who clearly knows what it's doing but is saying otherwise. Still... as any expert on any field keeps learning new stuff, they become more and more aware of all those things that they ignore. Therefore you have Socrates there saying 'I only know that I know nothing'.

@bonuscreature

4 жыл бұрын

Leandro Tami Dunning-Kruger effect is about both novices overestimating their ability AND more knowledgeable people underestimating theirs.

I love his passion, excitement and of course his knowledge.

Hi there ! You did a marvellous job repairing this board. Your methodology of fault finding and fixing is very good. I also wanted to say that it’s always a good idea to use good quality chip sockets. I’ve encountered also many issues with bad sockets at work. Nice and crisp video too, very informative !

Well done!

Your videos are always an education.

@Jerkwad152

4 жыл бұрын

Yes, I think so. :3

Great watch. Start to finish. Learned a few things as well. Well done, bud.

This video is pure relaxation for me - great channel!

Oh dear, this poor Commodore sure has seen better days, it's always satisfying to see a machine fire up and just work after you spend countless hours tackling its problems. ------------------------------------------------ Aye, while it's not as impressive, I too, got my hands dirty and started tackling a project: my friend's Amstrad CPC 6128, it won't read any disk, and the floppy drive makes weird noises... And it has a intermittent fault where the keyboard intermittently stops responding. For now, I've dismantled the drive and found out that the belt is gone (it has melted away, and trust me, cleaning melted rubber is a pain, thankfully I had rubbing alcohol on hand, it more or less worked fine), for now I haven't put it back and will need to order a new belt. After that I'll move onto the keyboard issue...

@ct92404

4 жыл бұрын

Yikes! It sounds like you definitely have a lot of work ahead of you! It's great though that people are fixing vintage computers and bringing them back to life. In a way, it definitely is helping to preserve a part of history.

@Alexis_du_60

4 жыл бұрын

@@ct92404 yeha in a way, it feels like restoring preserving a ancient artifact from the past, so it doesn't fade into the abyss of the forgotten things. That aside, this Amstrad is quite a simple machine, it's just yet another Zilog Z80-based computer, nothing too far-fetched, they were built to be cheap (from what I heard about them), but surprisingly the one I'm restoring has held up pretty well (save for the drive belt melting and the keyboard ribbon connector being flaky), though on the outside it's near mint, save for a few blemishes, but hey, it adds a bit of character to the machine, right?

I might just be a geek :-D But even though I have spent ages online, watching all kinds of videos, this video is one of the most interesting and satisfying videos, I have seen

@parishna4882

4 жыл бұрын

That was my impression also. It was good to see an actual diagnostic video test, rather than someone who just knows and thinks the viewer knows so they omit anything that actually helps us newbs understand these things. Nice vid Adrian!

Thanks for this video. The more problems you had and were able to fix the more I learned. I'm actually wanting to build my C64 from scratch sometime in the near future and had help from others where to buy parts. Even was given options of upgraded replacement chips that I would like to consider. My currently C64 had a bad VIC II chip and was able to diagnose and replace without any previous experience (I suck had soldering but was able to clean up my mess). I'm doing some researching right now before I consider a complete build. Thanks for sharing this video. :)

I REALLY need some training in this area, and your tutorials are giving me a good start!

Patience of Job. I would go insane trying to fix that Commie.

I never liked that cassette high-side switch circuit. When I was a lil un using my C64 with a data-cette, I had at least two repair visits that I remember having to take the computer in to get the transistor replaced. When I went over to disk drives that issue was effectively bypassed. I imagine nowadays that the high side switch is akin to an appendix on a C64. Seasons greetings, thanks for the content from 2019. Cheers,

@ulfen92

4 жыл бұрын

Makes me wonder why they didnt use a PNP transistor instead as a switch. That would have made more sense in that highside switch circuit.

@EngineeringVignettes

4 жыл бұрын

@@ulfen92 - Thats' a good point. I think the NPN was used as the circuit acts also as a linear voltage regulator. The zener on the base ensures that the emitter voltage is clamped at .6v below the zener voltage. This helps to roast the transistor causing it to fail as there is no heatsink on it. -_- Cheers,

@lwilton

4 жыл бұрын

That TO-66 is a pretty husky transistor for the purpose it is used for. My experience was that the cassette drive would get plugged on incorrectly or an aftermarket cable would short the output of the transistor to ground and fry it before the 9V fuse went.

I don't repair boards any more but I felt quite nostalgic watching you work. took me back to the 80's when I was about 30 yo I designed logic circuits for lighting controls, we did wire wrap because most everything was a one off. Thanks for helping me feel young for about 40 minutes. You do good work and your troubleshooting logic is impressive!

Excellent trouble-shooting and circuit analysis. WELL DONE!!! 10/10

I was an Atari guy back in the day... why am I watching 41 minutes of a guy repairing a C64? at 1am?

@adamw.8579

4 жыл бұрын

Me too, my first serious overhaul was expanding RAM in my Atari XE to 256kB for Sparta DOS RAM-Disk. Works lika a charm for few years until PC come on my desk.

@davej3781

4 жыл бұрын

I don't recall doing any hacking on my 800, but I did hack and ultimately killed my 520ST. First I separated the keyboard from the rest of the computer, because I hated having all the cables stretched across my desk to where I wanted to have the keyboard. Initially I just had the keyboard in the empty case connected by a small cable to the mainboard at the back of the desk under the monitor stand; I planned to cut the case down to a more proper keyboard size, and then put the mainboard back into what was left... Never got to it though before I killed it doing a memory upgrade with some bad solder from radio shack. Then I got a Mega ST2...

@VTX00128

4 жыл бұрын

Ah this take me back to my 386/486 chipset days

TS100 tip: if you've got the XT60 to DC barrel cable that's commonly offered with the TS100, that cord is a piece of junk. The wires in the cable are awesome, but the strain relief is bad - it makes the wires fray and break with moderate use. Check for continuity in the DC barrel while manipulating the strain relief. You might need to strip the molding off it and resolder, hot-snot the thing back together. Maybe.

@0xbenedikt

4 жыл бұрын

Hmm, I also had my TS100 power jack go bad, but it was the wallwart Sainsmart one. I've since replaced it with a JBC Compact iron, but I would still like to fix the old TS100. Perhaps I might try bending the lever in the barrel jack a bit inwards.

Adrian, thank you for taking us on this journey. Your diagnosis methods are just fine. As I’m sure you know, there is seldom a mapped out troubleshooting guide that will cover all potential faults especially when stacked up like this board. One of the most expensive aspects for NASA and Military projects is the need to reduce fault isolation as much as possible even if there’s only a once in a million chances the fault condition will occur. Working on commercial products is all learning the obvious weaknesses, and a strong sense of intuition. I see nothing wrong with your methods. Teaching them to others especially while showing all the ugliness builds that intuition. Thanks again!

Always nice to see vintage systems saved. Great detective work there 👍

I enjoyed watching you diagnose this computer. I am also a novice at Electronics. I would say you are about a year ahead of me or so. I have learned quite a bit by watching you. I've noticed that the schematics are starting to look a lot easier to me. (they make a lot more sense). I would imagine as with any new language, it all seems overwhelming at first, but after a while things just start falling into place! :-)

34:57 "Bring in the Logic Probe!" - Sark / TRON

Another bread box saved - thank you for sharing this. I think your deductions and methods are quite good, and a lot can be learned from them.

Very informative. Thank you. Repaired a fair few 8 bit micro's myself now and these are common problems although this particular C64 seemed to have all the common faults on one board!

"I'm an electronics novice"- made me spit out my wine 😅🤣

@tindrli

4 жыл бұрын

same here

Adrian was trying to be humble but the effect of that humorous "total novice" depiction likely sounds too detached from the stunt so much so that 98% of his audience would be left feeling they don't even qualify for the title of "novice" anymore.

@Ben31337l

4 жыл бұрын

I think that amateur might be a better description for us common folk.

Great Video, Really enjoyed the troubleshooting steps you took. I have an Apple IIe that had a bad power supply that I fixed. Feels so good to get this vintage stuff working again.

Such a complex investigation and fix! Wonderfully presented and accessible 🙂