Can I Fix this 46 Year Old Computer? | Commodore KIM-1 Repair 

Edit: Sorry about the background music. I dialed it to -35db and somehow in processing on YT it perked up again. There's a lot of free background music on offer out there for YTers but so much of it has obnoxious segments - trumpets, guitar, drums, pianos, etc. I get that the artists (whom I am grateful for) dont want to be boring, but that's kind of what we want background music to be. I wouldn't mind trying something other than slow jazz but there's just not a lot out there that fits as proper background music, and I feel like the right music makes the video feel more professional. Anyway, next video I will assassinate any loud instrument solos I come across. Sorry it's been.. um.. a really long time.. but, life happens. Anyway, I managed to squeeze this little side project in, filmed and edited in record time. Sorry - no animations/3d.. it would have added weeks to this and RU-vid would bomb it anyway. But the next video will have those, and it's not far from being finished!

Probably around 1986, when they were still being used in university computer labs to teach wiring up your own digital circuits. Crazy advanced stuff like adding massive amounts of memory to it. I didn't have the lab, but my girlfriend did, and she showed me her Kim-1 station in the lab where every student had one. I was a mad software hacker back then, but I was like dang, I had no clue you were off the chain as a hardware hacker. I just though she was an intense physics and math nerd. Cern never hired her, but she later got a job at Intel writing device drivers. I could assembly level program my C=64 back in my dorm, but this girl after her Kim-1 lab could not only assembly program one, but friggin build one as if she were Bill Herd

You got it running. Not get Doom running on it. 🤣🤣🤣

The KIM-1 literally looks like a time machine board, fitting with your channel name.

I'd still highly reccomend the Hakko desoldering gun. It's expensive, but the time and frustration saved is more than worth the cost of entry. I use mine almost daily, and i'll never go back to the manual solder sucker. Great video, as always!

Not seen yet- thumbs up! Your channel is my absolute favourite one. Best regards from an absolute CBM/PET guy in germany! ;)

The KIM-1 was the first computer I ever programmed. My high school electronics class had one that nobody had played with. This would have been 79 or 80, long time ago. It was in a wooden box with a smoked plexiglass cover. I thought the chips were socketed on it, but again, long time. I'm sure I typed in that exact program and a bunch of others that were in the Xeroxed manual, although I think it was spiral or comb bound. I thought it was the coolest thing in the world at the time. I wanted to take computer classes but they insisted I had to take advanced algebra as a pre-requisite. I didn't do well, I was so mad at being forced to take the class that I copped an attitude and ditched class... to go hang out in the electronics lab! Needless to say, didn't pass that class so I couldn't take any computer classes. I ended up begging my parents for a computer kit in the back of Popular Electronics. It was expensive (for the time), but since it was educational, I got it for Christmas. It turned out to be a Sinclair ZX-80 with a whopping 1K of memory! The best thing about it was it forced me to learn machine language due to its efficiency. 40+ years of programming computers and micros, I have as of yet to apply anything that was taught in that advanced algebra class in anything I've done. Calculus would have come in quite handy (PID loops, Fourier transforms), but advanced algebra has been worthless.

I bought mine in 1977. Built a s100 motherboard for it. Good times.

I just love that end 70's era "analogue" routing!

Well done with the repair. In 1977 there were (almost) no home computers. Enthusiasts jumped on the affordable and expandable KIM-1. 4k expansion boards were simple. Connecting to a teletype was simple. Programs were hand compiled into 6502 machine language with paper and pencil. For the first time a regular person could buy a pre assembled computer and learn how they work. That's what makes the KIM-1 special.

Excellent content! One of the best in the retro space.

Congrats on the successful rescue! Reminds me of my own multi-year effort to get my TIM-1 system (based on the MAI "Jolt" with a 6530-004 chip) running reliably. It would run for a while, then refuse to fully boot. Finally tracked it down to a marginal jelly-bean 74xx chip and a bad socket. Sheesh. The key piece of troubleshooting equipment was an HP 1662 logic analyzer with which I could watch the CPU trying to run, then fly off into hyperspace. The bad chip was in the address decode logic that enabled the 6530's ROM. I built the system in the mid-1970's. The CPU and TIM chips were purchased from the Wescon show where they debuted; the Jolt board was purchased a year later after I got tired of trying to wire-wrap what would basically be the same thing. Already getting lazy, so young in life. It's got a Bay Area TVT for the terminal, high speed paper tape reader, and an 8-bit DAC that did data acquisition for my masters project. Blows my mind that an Arduino can do the same, so much better, for so little cost. I have paper tapes for Tom Pitman's Tiny Basic, an assembler and text editor, and a few random utilities from the day. Now all I do is play Hunt the Wumpus on it. Fun times. I wouldn't mind finding any other games, if they even existed.

I think I learned assembly on a kim ! in college in Newfoundland in 1987. I'm not sure but the keypad and display looks familiar. I remember it was in a black suitcase.

Nice! Very satisfying to see life in this old board again.

I remember seeing the KIM-1 in Popular Electronics and wisely deciding to buy a complete computer instead.

I have watched Adrians Digital Basement quite a few times. And in some of the videos he has posted where he was repairing Commodore 64's, he has found new chips that are replacements for some of the older Commodore chips. Now I can't say for certain, but maybe someone in the Kim-1 community might know of replacements for the RRIOT chips

yeah thats a great feeling when you see something runs for the first time. id recommend getting some flux and copper braid for repairing the shorted lines. i also couldnt see buying the hakko at that price and went with a zd-915. That with a hot air gun (for the ground vias) was magic doing some recap work on some motherboards recently.

That Radio Shack looking soldering iron might be part of the difficulty. A good soldering iron iron is a "must" when dealing with higher density electronics.....

Wooo! Congrats on getting the KIM working! That is fantastic, I an excited to see a KIM up and running. I simply know no other way to add the numbers 2 and 3. Believe me, I know how you feel. I have had a KIM for years and have been avoiding plugging it in specifically because of those RIOT chips. As long as I don't try to power it on, it might still be a good and working KIM. I know I can't be the only one with a Schrodinger's KIM in their collection.

awesome to watch whilest making food ^.^ always happy when you upload

Great video, I love seeing old hardware that I know nothing about!

Ayyy! The Traveler Returns!

I'm honestly never a fan of modifying rare, ancient hardware like this. On the other hand, it is cool to see it work!

Y’know I never heard if KIM until right now Sounds really neat tbh :0

I have a SYM-1 in my parts box. I hope to get it up and running, It was used for training/projects at a University. So it has all kinds of bodges wired on it.

Glad to see you got it working after so much time. I really like the concept of a device like this... I wonder if any modern kits that can be built to get a trainer similar to this exist?

Yeah, best solder-sucker right there. Some re-printed KIM-1 manuals on Tindie, BTW.

Well done vid! I do have a desoldering iron but i prefer the same japanese desoldering pump with the silicon-tip. Its convenient to use in case theres not much desoldering to do anyway.

Love it!

Ótimo video muito bom, o incrível KIM bons tempos aqueles computadores com teclado HEX.

nice bit of nostalgia for me, my dad had a couple games set up for me to load on one when I was about 6 or 7 years old, wumpus was my favourite, but also enjoyed a game where you had to identify farm animals.

Ah, the joys of closed source hardware to make an additional buck. Wonder if I should finish my variant of the 6532 adapter I started years ago (never owned a KIM-1 but was asked if I wanted to repair one years ago - I declined because very early minimalist systems don't exactly interest me). Design was based on open source documentation from 2013 by Ruud Baltissen.

If you wired up an external screen to it and wrote a program, I think the KIM-1 would make a decent novelty clock to have in the office or workshop. Would at least save it from being stuck on a shelf collecting dust unused.

I think the most annoying part is how the 6532 RIOT chip (as used in the Atari 2600) has a completely different pinout from the 6530 RRIOT, even though they're basically the same inside. So you *have to* have an adapter board. The board you used is about as slim as you can get it. And the worst thing a board like this can do for you is... nothing. You turn it on and nothing happens, while you're wondering if something is getting fried. I have an old board I've been working on where the reset circuit was stuck on. It took me a while just to confirm that was really the problem. I had to mess around with cutting and un-cutting traces before I found that it came from a trace that ran under five chips. Llifting a 74LS00 pin and bodging on an electrolytic capacitor to ground (there was already a pull-up on the reset line!) gave me a better reset circuit. I still haven't figured out yet what was wrong with the original reset circuit. But now I know what you mean about the feeling of finally getting an old board fixed up, even though I still have a lot left to make mine useful because it wasn't supposed to be a trainer.

May I suggest that you add rubber feet to the four corners of the board ? It might add some mechanical stability to it.

Interesting to see it in use. Thanx. A personal preference: i think background music made it hard to follow along. But I guess ymmv as one say, could be my brain.

Wow! A solder sucker I want! 🤩

Does this thing have an "expander" unit like the Heathkit ET-3400 had (the ETA-3400 box), so your single-board computer could get input-output to a simple terminal and thus you could run Tiny BASIC on it? I've never heard of one for the KIM-1, but you know that the cadre of '70s-early '80s homebrewers would come up with something.....

consider getting a syringe of solder flux for smd components, you can also apply this to the board when soldering through hole components. I didn't do this for years myself, and was surprised how much this stuff helps to avoid bridging solder joints and keep the solder where it should be.

Ah the KIM, definitely on my want list. Unfortunatly probably out of my Price range. But hey i got lucky on other incredibly rare stuff so maybe one day.

13:55 - I have a golden rule on my projects. Absolutely NEVER use stamped pin sockets. Use ONLY machined pin, gold plated, sockets and you will never get the "I have to press right here to make the board work" problem ever again. Yes. The machined sockets cost more. Still cheaper than the lost time. TIME. The only resource you can never replace.

Notification Squad!!! :D

I have vague recollection that there were 3rd party terminal and tape drive connectors available for the KIM-1; was that the case?

I've had one for years, with both MCI 6530 chips fried... I'd love to repair it, but where to find those custom mask RROM Riot chips?! :( Are those retrospy circuit boards still available?

I wish they would make hex key pads like that still. I really need some and the ones available now don’t include extra keys like enter or go. Just 0 thru F

The KIM-1 was made by MOS Technologies. Not Commodore. It was a prototype. It wasn't even branded.

If you had enough of this KIM-1 then I could try to find some Canadian Dollars and offer you a new home for this computer. There are numerous fields where it can be used, as an egg timer of as a trainer for Morse-code. I saw a book once with a large dozen of possibilities for programmes. To be honest, it isn't mutch that can be done. Sitting pretty is the almost the only real task for a KIM-1.

Hmmmm...... What did you do to the real TechTimeTraveller?

If you ever wanna sell this one for $100 hit me up. At least it will stay in Canada😂. The kim one is one of those holy grail computers for me. Even considered a replica that could be completely compatible but as much off the shelf true hardware with as little emulation as possible.

SUBSCRIBED

put some red plastic film over the displays for enhanced readability

I have a Swedish KIM-1 clone in my collection. The company was called Digitus. Serial #008. :) It does not have the same board. One of the differences is that it has two RAM chips instead of eight.

I don´t mind the music or the loudness. All´s good here.

What were some typical uses for these computers? It seems more a calculator than a computer. Best wishes.

What happens to dead, unobtanium chips? I am guessing that they are resold (at a Canadian-seller discount) as "untested".

Congrats on getting it running! It’s too late now, but I would have purchased the proper card edge connectors to solder your leads to instead of soldering directly to the card edge of the KIM-1. You’ll never be able to remove the tinning you added to those nice gold plated cards edge pins.

It's okay guys, we're reaching that point where we are simply going to have to keep transplanting modern parts. Nothing we can do about it, it's just the new normal, and we shouldn't fret.

Do you have a link for that solder sucker ?

Canadian E-bay sellers. Yea a no-go for me. I purchased 3 pieces from Canadian sellers. The first two I took a bath on. Both were stopped by UPS at the border for customs. The first one was a Sun Sparc 5 about 6 years old when I purchased it but I was told I needed to pay 500 more to get it shipped to me. Second one I don't remember but also stopped at UPS Customs and I had to pay $$$ to get it. 15 years later I got a Uniden 2025 *BROKEN* for parts to fix my one. Made it through UPS customs OK but spent two weeks "in transit" on the US side. I have had less trouble getting obsolete items through UPS customs from Bulgaria and Peru (slide rules) than Canada. Canada is a hard NO due to UPS customs.

When did they start calling the 6530 a "RRIOT" chip? I always called them the "Kitchen sink chip", as in "everything but the..."

Good job getting it going :) You gotta mount that on some plexiglass or plywood with some good spacers. You might want to measure the actual voltage on the board and verify that you have a good +5VDC there. As you already may know old electrolytic caps tend to fail. I see a few that you could probably replace. Applying power will sometimes "Reform" the caps. A possibility is that some bad caps could have been pulling down the +5VDC and after awhile they reformed the longer you had it on. That is why it magically started working. I have not seen a schematic of that board but if there are any caps across the power supply it can be a possibility. Also on the old S-100 type boards they usually have shorted tantalum caps that nee to be replaced. So happy you got that BEAUTY running again.. GREAT JOB !!!!

Is this LGR????

Great content, but the background music is always too loud and distracting.

5:30 well a 6532 could be used, with an external rom, which can be done using some 74 logic gates to mimic a 6530 with 128 bytes of extra ram using bank switching

wow

Maybe a Machine type Socket would have been better to mate with the pins on that replacement board...

Pour Out some Geritol for our buddys' Senior Moment

yeah you 100% need to use a turn pin socket with them round legs.

I really want to know how these would have worked for HVAC!

The reason why those of us in the USA don’t buy Canadian eBay stock is because Pitney Bowes breaks everything.

as it's replacing failed part? on basically "ford of cars - any if black", look wrong why blue? greens the default colour of PCB's,? Idea to make more pleasing on the eye? could not mount on the back of the PCB board? same sockets pins everything just build burger/pancake, in reverse you will not able see the chips as they will , squashed to the back of the kim-1 motherboard, and the win, win, no new chips on view? and assuming the Kim-1 is mount base, in display case the back wil not be on view? and as is no an entry hole where old chip was located, the history art, restoration, old chip cleaned up, bit sticky foam or something placed back in the hole, (just check shorting thing out, as only cosmetic now?

I prefer the dark blue mask. Whats wrong with combining old and new tech?

Wish I could find a KIM-1 for $115. I kick myself for not getting one of the clone kits when they where on ebay just to mess around with one. Oh well I guess the Git-hub with the reproduction gibber files and PCBwaaaaaaay is my only hope for another poor Canadian that is in this hobby :(

I hate to see wires soldered direct to edge connector gold plated pads.

Jazzy Nokia intro, what?

Микролаб КР580ИК80 907 :)

The reason those chips die is because their I/O lines are ran straight to the edge connectors with absolutely no protection whatsoever. It's a shocking design! They should have added some ESD and short circuit protection. I know they were trying to keep costs down, but they were selling these into an environment (schools/colleges etc.) that were going to absolutely abuse them! Terrible design! 😆

grufty Musik

Sorry for being dense but what is the point of that "computer"? It can´t be made to only add single digit numbers, even a mechanical calculator would do it faster that this demonstration. What was it made to do by design, why does it exist at all?

why would anyone pay 600 bucks. for a kim-1. it can't be 'nostalgia' for if you (like me) figured out how to use them when they were new (and so were you ;) you can just build your own nowadays. brand new. for like. 50 bucks. and put all the other chips in there you want too lol. i mean i can see why people pay like 20K for a white ceramic chip version with the rotate bug and all that. -those- belong in a musem. all the rest of em are just old evaluation kits, somewhat abused as prehistoric plc's, for a bunch of chips of which millions are sold each day to this very day. lol.

Why do americans/canadians say "soder" and not "soLder"?