C64 Repairathon! Part 4 - Fixing the #1 machine and performing the "weak video fix"

[@LGR]

This has been a highly relaxing series, watched them all start to finish. Thanks for posting these!

[@Alexis_du_60]

I second this, this series has really sparked my interest in C16s and maybe the C128s.

[@sersoft_corp]

Next series: Adrian's Camera Repairathon - Part 1 of 34

[@stamasd8500]

I'd watch that.

[@theannoyedmrfloyd3998]

He should just reformat the memory card.

[@benbaselet2026]

Just roll back from the latest firmware revision... you know the one which breaks the camera so you are more tempted to buy the next version. Since phone makers are doing that why not the cameras too eh?

[@santi308]

maybe needs a firmware update

[@sersoft_corp]

Linus tech tips: Let's watercool it!

[@geraldspratley4637]

What I enjoy most about your videos is the brutal honesty. When things are bad, you don't gloss over it, but it becomes part of the process. Awesome work as always Adrian.

[@joed2392]

Great Work !!! Long ago..... I bought one of the first 100 C64's sold in North Carolina ! I had to get up at daybreak and drive 100 miles to the state capital to get there before the store opened. When I arrived, there was line of 50 to 60 people at the door ! I'm glad my alarm clock worked and the power didn't go out ! Because I had called the store every day for a week to get updates, I found out they were only going to get 100 due to production problems ! When I saw the video color fringing ..... I understood the production problem !!! It's really AWESOME that you are bringing these machines back to life !!

[@dougjohnson4266]

Almost as happy as you are to see these C64's working. Congratulations sir!

[@dr.feelicks2051]

That was fun. Haven't had a soldering iron fired up for years. Before I started down the MacIntosh path I was heavily invested in a C64 setup, GEOS, 1581 drive, 256K Ramdisk-(which I turned into a 512 during the RAM embargo ('85 or 86?)by socketing the board and phoning every Radio shack in Town and getting old shelf stock for 1/10th the going rate) a win for sure. Thanks for sharing, fond memories.

[@YourMotherSucksCocksInHell]

Sad to hear that you took the evil path.

[@Calphool222]

Really love watching Adrian's videos. Adrian: I'm an electronics hobbyist as well. I repair 8-bit machines also. I had a suggestion you might do (habit a TV/VCR-repair guy taught me years ago). Get a Sharpie oil-based paint marker, and when you mark a chip as "okay," instead of putting a check mark, put a checkmark and a date code (like right now would be 0820 - 8th week of 2020). This helps when you're working on something the second or (God forbid) third time. Chips do tend to degrade over time.

[@Wenlocktvdx]

Great viewing. I used to have a Radio Color Compute back in the day and we needed the shields on the PAL version. The r.f. radiation would mess with the TV and I often had the rf cable wound round a ferrite rod just to get a picture. Big relief when I got the CoCo 3 and could use a monitor. I did put a video amp in a few peoples CoCos to get around the rf issues. I ended up doing quit a bit of tinkering too, converting the radio shack hi res joystick interface for CoCo 3 to work with the CoCoMax graphics software. They used a slightly different circuit and the Radio Shack circuit could be adapted. I managed to stuff a 4PDT switch inside it, and a DPDT switch to bypass the cassette port to a DIN line socket in CoCoMax mode. The RS version used the cassette port to generate a ramp for the comparator but the CoCoMax circuit generated the ramp on board. Those were the days.

[@Carcenomy]

Seeing this whole series makes me wonder why I haven't gone for a dig through my pile of C64 boards to see how many can be brought back. Thanks for the inspiration as always Adrian.

[@alienrenders]

This was a joy to watch. Reviving C64's brings a smile to my face :)

[@mqb17]

I've been binge watching these videos all day. So glad I found this channel!

[@bradkamrath]

AMAZING video series, Adrian! You've taught us so much about basic AND advanced troubleshooting techniques and gave us some great insights into the equipment used to repair our old machines. Stellar work, brother!

[@johnpossum556]

I loved the way you troll the trolls with the RF shield issue. LOL!

[@leonkiriliuk]

There are 2 other fixes you can do to this board to make it better. There a fix to the 555 timer to make your multicart work. There’s also 2 ceramic caps that get installed in place of the the 2 orange caps by the SID to make the audio sound better.

[@BrianOfAteionas]

Also, someone else in the comments recommended tying the audio input pin (not used) on the SID chip to ground in order to reduce noise.

[@magnusboman1576]

14:24 "Black fff Screen" I heard that, haha! can't blame you though ;D

[@AShifter]

Been loving this series. Keep up the good work, Adrian!

[@eatportchops]

Trying to Restore a C64 Silver label (no rainbow or 64 on the main label). Thanks to your videos I tested the power and the 7805 was bad, no 5 volts. After replacing the 7805 got a very distorted yellow start up screen. After taking the socketed chips and using contact cleaner I got a normal Blue start up screen, but it didn't last long now back to the distorted yellow screen. Have you ever seen this behavior? Back in 1998 I started picking up old computers to collect and fix but never had the time to do much with them. Now that I retired I'm trying to teach myself how to fix old computers. Thanks so much for you very instructive video. They are the Best!

[@jazj204]

Adrian, are you an insomniac or just dedicated to getting these vids out ? Working until past 4am on this one and past 5am on Part 3 ! Either way, thanks for making them - even though a lot ( ok, most ) of the technical stuff goes waaaaaayyyy over my head, they are entertaining and very satisfying to watch and I am truly pleased for you when you cheer when you hit on a solution to an issue. Keep em coming.

[@FrankEBailey]

I've been going back to earlier episodes, particularly the C64 instalments, and they're still lots of fun to watch! Keep on making episodes of Adrian's Dirigible Bass Fishing! errr I mean Digital Basement....

[@julienderiviere4907]

Hi from a new fan! :) Your videos are... surprisingly soothing, for some reason :D As a fan of vintage computers, I just love your work, and I have to admit... I keep watching your videos over and over again ^^ Keep'm coming, keep up the excellent and passionate work!!! Love from France

[@mikethemusicman1978]

Wow, I've loved this series, It's given me some knowledge which beforehand I never had, thank you so much for the information and fantastic video series. I now want another C64. That video where you repaired and cleaned up the debris, ant filled one was spectacular. Thank You so much for the great work you do in bringing these solid computers back to life.

[@Halterung01]

Gotta love that K7T Turbo2 heatsink on that C64s chip :P

[@Supadupanerd]

I literally thought for a split second: "Wait he has an athlon in there and that's a sleeper build?! " Before I came to my senses

[@alexandermaasland3494]

Hi Adrian, your repairathon became a watch-a-tron for me, I quite enjoyed the videos (as usual) :) Thanks for posting these marvels!

[@dhpbear2]

8:45 - Why is part of the image blurred out?

[@emprsnm9903]

@@adriansdigitalbasement Thanks for answering that, I was wondering too. One of life's little mysteries. Of course with youtube's content matching who-har, it could have been a paused movie you were being proactive about :)

[@AndyGarton]

Great series. I'd love to see a follow up covering the case cleanups!

[@garthhowe297]

I was very impressed with your perseverance to fix these. That #1 machine would have driven me mad. Thanks for all the great troubleshooting tips. Great series... even if you threw the shielding out... lol

[@coryengel]

Suggestion : when doing before/ after comparisons of video, side by side would be best. (Or maybe toggling back and forth between them.) thanks for a great series.

[@SidneyCritic]

Or split screen side by side.

[@benbaselet2026]

@@SidneyCritic Split screen camera shots with the same exposure etc. settings would be awesome yes.

[@Gadgetman1989]

Adrian, thank you for all the work you did in doing this repairathon, now if I ever get a c64, this series will help for testing and troubleshooting, you have my deepest thanks

[@mrjakeisnumber1]

"A lot of hissing and weird noise" -Man who trashes every RF shield he comes across

[@theannoyedmrfloyd3998]

Would filter caps help?

[@jaycee1980]

The SID has an audio input pin which is frequently the cause of noise appearing, as it's unused in the C64. Tying this pin to ground usually quietens things down

[@emprsnm9903]

I'm pro RF shield, except when they hold in heat that shorten chips lifespan. Anybody know why these SID chips seem to go goofy? Bad power, or long term heat exposure breakdown?

[@mdolan900]

@@emprsnm9903 I'd love to know as well. I have two C64s and both have had the SID chips go funky.

[@dos1044]

I just love that series of repair videos ;)

[@ivanbiasutti4567]

me 2

[@mark_tilltill6664]

Thank you for bringing these back to life, improbable redemption!!

[@cassadagaa]

Love these repair videos. Thanks for all the tidbits and information!

[@8bits59]

As a radio amateur, I can tell you right now that those RF shields are there for a reason. Just about everything from 0.5 MHz to 25 MHz gets wiped out nearby the computer once you remove the shielding. If you don't do a whole lot of radio work, it probably doesn't matter. However, I like to keep those shields not for originality but for practicality.

[@deborahberi3249]

Adrian, why not just repair the known issue with that 326 Series Mobo with a 1K Resistor between Pin 9 on the 555 (U20 I believe) and the reset line south of U22 if I'm not mistaken. It will fix EF3 and some other Accessories. Also, you can clean up some of the SID filtering by changing the Caps above the SID while you're at it. As for Ray's 220Ohm brightness fix, I though it was a 150Ohm fix? I bough 150 Ohm resistors since I was simply planning on removing R10 on 4, Yes 4, 326 series Mobo's. Def enjoyed the Videos! -Mark.

[@at90systems]

Would love to see a repairathon on VIC 20s as well especially the cost reduced models seem to have more issues with those myself than the regular ones in regards to full repair.

[@danieltufvesson1349]

I really enjoyed watching this. Good work! I noticed one thing though. When you were scoping the buses you could see collisions indicating two or more chips driving the bus lines at the same time. It may or may not have been the clue to save you some time :)

[@terryraymond7984]

you can use modeling clay to keep chip sockets and components in place while soldering.

[@skideric]

Gotta get around to checking 6 or so bread bins i have.Few were checked yrs ago,which means diddley now...LOL ! Not been motivated since i have 2 C64C's,128D & 1 Bread Bin working & using currently.

[@bairfamilyfarm1336]

RF shields, in computers and transistor radios, not necessary for operation but made the FCC happy. Now if you're working on HF ham radio receivers or Transceivers, you better put those shields back in or your going to be listening to your radio's own guts everytime you hit a blank frequency!

[@jackdrizzleshizzle4389]

Really love the series!! Want to repair C64's myself now

[@Tannlore]

I really love these videos. So relaxing and super informative.

[@lostindesolation2810]

Sometimes the filter caps are to blame for weird SID malfunctions. I had one where they caused glitches in one of the voices. Worth a shot I'd say, unless the SID problems persist when swapping boards.

[@lostindesolation2810]

@@adriansdigitalbasement What a bummer. Yeah it really is the sid and vic2 you pay for these days.

[@HiSmartAlarms]

I love these! Keep up the good work. Please make more of these series when you can get more c64s

[@lk0657]

That 8-Bit Donkey Kong theme will never get old!

[@Plan-C]

"Look at that! Black fffffscreen" LMAO. Could hear the frustration rising. Been there! Great job! Beware the rabbit hole lol. It feeds on frustration!

[@esshahn]

So good you found the issue on #1, congrats!

[@XavierBergeron]

Love the back to back uploads!!

[@xephorce]

love the music during the spead up parts way better than hearing high pitched fast speak. lol

[@zidane2k1]

The fast speak is kind of funny though. Maybe both?

Adrian ... this place is AWESOME !

[@ProjectGeek1]

Finally finished this series, I must say great work! I am quite envious of your scope and soldering gear. :)

[@XDavidEllisX]

Thanks for posting this series. Loved watching throughout the process.

[@10MARC]

I appreciate the great series, Adrian. You gave me lots of good ideas. I could do a three part series on all these A2000 motherboards I have in my studio!

[@justindelpero]

Thanks Adrian. This series was excellent, was really fun to watch.

[@winstonsmith478]

When these boards were manufactured was there a test jig like a bed of nails test jig used to test them? I'm amazed that the PCBs don't have marked test points with maintenance schematics where scope screen photos are shown at those test points. A bed of nails test jig at the factory would explain why there aren't any.

[@johnchanalyst549]

Great Work Adrian - I have an intermittent composite video and no RGBI so may have to bypass or remove Modulator. I installed molex connectors at CN12 in my C128 to provide easily pluggable Logic Probe power. Now I have to see if I can afford a Mini Pro and Your Chip Puller! JW

[@juddsandage]

Adrian there are replacement aftermarket PLA chips that solve all the issues the stock ones have, and are more resilient too, can take being dropped... ask me how I know... ANYways, I might also suggest some issues might have been bad solder joints, my one and only C64 (and I am the original owner) had random issues with black screen, resolved with the replacement of the PLA and reflowing the solder on the power input leads. Keep up the good work!

[@P5ychoFox]

An epic repair. I really enjoyed this. Many thanks for putting all those hours in making these videos.

[@mdolan900]

I got my C64 for Christmas 1984 when I was 11 and the first thing my uncle (An electrical engineer, or general computer genius) told me to do was to remove the RF shield! It must have been a known issue in the community back then as well.

[@earthlydescent]

Hey Adrian, could you do a detailed overview on how you use your Easyflash cart?

[@vhfgamer]

This gives me some good ideas on fixing my C64. Unlike some people, I don't have multiple C64s to play with. I have just one, and I'm lucky I have it. Maybe I'll start with doing away with that old defective PLA.

[@tmburns4]

I really interesting series. Thanks for making these!

[@m7hacke]

Great series. I learned a lot and I'm very impressed with your troubleshooting skills.

[@bobz1736]

Great job. Loved this series 😀

[@jumhig]

Great series of repair videos. Would love to see you repair some Atari 8-bits.

[@knghtbrd]

I could see keeping the metal shield whose top provided some heat sinking on that later rev board, but that cardboard crap is best gotten rid of. Sadly I doubt it is recycleable anywhere (I know it's not in Portlandia where our recycling program is stupidly ridiculous!)

[@chriswareham]

It's been a very instructive series. I need to replace one of the CIA chips in my C64, but I'm going to invest in some good quality IC sockets first!

[@yuchong1704]

Great series. Love the honesty.

[@janpedersen9120]

No matter what i learned a lot from this, so i subscribed. So thanks for this series.

[@lordmmx1303]

Awesome 4 episodes. Watched them all. in part 3 when you tried donkey kong with bad sid, I actually liked that messed version :D sounded more hardcore

[@DEMENTO01]

YAAAASSS. Love these videos. Thank you so much for all the great work you do, is really entertaining yet interesting and i always learn a thing or two

[@JakeWorrell]

This has been a great series, thanks for sharing!

[@willyarma_uk]

I'm going to call you "Adrian Black screen" from now on ;) Great series, love your vids.

[@willyarma_uk]

@@adriansdigitalbasement This is my favorite retro computer channel, mainly because you go in depth on the electronics side of things, I really like that. Sorry about bad name joke.

[@LucaViolini]

"Adrian Black fff screen"

[@BollingHolt]

I've never owned one of these (working, anyway) nor any Amigas. I'd love to have a couple one of these days!

[@unebonnevie]

You can use the TL866 programmer to test logic chips? I didn't know that! Cool!

[@adrianosbrandao]

The series was great, thanks! (And it was very funny to watch Angry Adrian in the last video, LOL)

[@azzajohnson2123]

It’s already burnt itself out hence it doesn’t get warm. I hate reinventing the wheel, when you have a gut instinct but you keep following the process instead of going with previous instinct on past experiences. Following the process will always save you time over the long run though.

[@kneehighspy]

thoroughly enjoyed series!

[@MindFlareRetro]

Great stuff. One can never have too much desoldering practice. And your camera ... sorry, but I had to laugh each time. Great series! Loved it.

[@billwilliams6338]

ADRIAN BLACK, can you make a youtube video going over each video section on the schematic and IC chip and what each section does how it converts the RGB signals to the H&V deflection and how it traces and draws the Image on the CRT screen, plus the H&V sync signals do what to the H&V deflection circuits and flyback.

[@DxDeksor]

Awesome marathon !

[@thediscoman2001]

Great set of videos i have an unrelated question, something caught my eye and its doing my head in, but what watch are you wearing on your wrist, it did catch my eye in the first video and it got me on what it is

[@danmanx2]

Nice repairs! I bow to your skills!

[@75slaine]

Great series Adrian. Learnt a lot too. 👍

[@MrParrothead60450]

Good stuff! Thanks for sharing. I loved the series.

[@MrJackSeverity]

Top video series!! keep up the good work Adrian :)

[@bwack]

Thanks for sharing. All time spent on the faulty ROM chip is more entertaining for us, and is how I think of it. There was no bus contention seen at the cpu, so strange that the Kernal caused the dead test ROM to fail.

[@britsluver]

I loved these. I knitted while I watched. Yaaaaasssss king

[@pepperm16]

What is that clock that you have above the Sony TV please? It looks very cool :-)

[@gazzawakey8087]

Great series really enjoyed them

[@brianseeley5997]

Great Video Series!! What do you do with all the machines you repair?

[@wayneaaron5818]

Loving the Commodore 64 repair video's. Notice that you have a trs80 color computer legend plate on your monitor and was wounder where you got it from?

[@thedungeondelver]

Classic Mac or Classic Apple fix-a-thon next?

[@billwilliams6338]

Thanks for going over that. I have watched your videos and you don't use the logic probe or oscilloscope to troubleshoot the bad chips, any reasons why? Do you know what programming language they used to program the C64 Kernal ROM, character ROM chips, BASIC ROM chip?

[@zenninom]

Adrian, love your stuff. Please setup a patreon or something for us to support you. Also, not sure if you know, but LGR mentioned your name in a recent video so that is awesome too!

[@piratestation69]

so what is the best vic chip revision?

[@matthewhapp8688]

Outstanding keep up the good work

[@christianberthelette299]

Hi . I have 1982 rev A board. Is 220ohm you have put on r10 on old resistor ? 220ohm + 300hohm =120ohm? How calculate in ohm ? Sorry i am begginer......

[@questionablecommands9423]

Since we're fairly local to each other, I'm curious if you happen to have an Apple ][e or //c that is cosmetically okay but otherwise beyond repair. I want to retro-fy my KVM, but I don't want to disassemble something repairable.

[@toastymuffin4153]

Channel catchphrase: its..... WORKING!

[@M0UAW_IO83]

Love that you got them all working (I've got C64 complete with 1541 and MPS801 which all the retro channels have inspired me to get out of the loft) But the shields, please, please replace them, RFI is a major issue that stops many people being able to enjoy their hobby, imagine if it was reversed and one of your neighbours had a habit that caused interference which made it nearly impossible to see the images from your vintage collection on screen, you'd be really annoyed no? That's how RFI affects ham operators and those cans are there to help stop it, it's really selfish to intentionally cause more RFI.