0035 We have a broken TRS-80 Coco 1 in the basement! (And a repair on my other channel!) 

i love how the box it was shipped in had the basement box checked

@Adrian - The floppy drive you are holding there was manufactured by a company called Remex. Most visibly, these drives were used in the DynaLogic Hyperion, and some variations of the Otorona Attache. My father had come across a massive surplus cache of them that were selling for $49 in 1984, when a typical double sided Tandon TM-100-2 would cost $350. We soon found out why: The heads were unbelievably misaligned, and required us to go through with a head alignment disk and a scope, to fix them.

"This isn't a drive repair video..." /me puts popcorn away

Adrian, thank you for the note at the end regarding the Telegram comments. I received one from an earlier video and decided to reach out. It was soon apparent something sketchy was going on and I put a stop to it. I hope no one else fell for it...

Yes, the return of the 40+ minute SMMC! My day (well, two consecutive days!) is made :D

At 23:00 Adrian commented on the wear marks at the bottom of the keyboard. Maybe this computer was used primarily for gaming? The wear marks on the keyboard appear to line up with the up/down (on the left side) and left right arrow keys (on the right side).

Man I just love seeing old computers like these that so obviously have been loved and have wonderfully complicated backstories. You can tell that whoever owned machines like these got their moneys worth and then some!

"Deoxit that socket!" 😆

39:45 Deoxit and a glass fiber pen. If necessary, cover it in SMD flux and tin the contacts like giant pads.

Adrian -- JMR Electronics made enclosures about that time for many computers including PC's. I worked at Micropolis and we used to purchase his enclosures and we sold drives in the enclosures. I knew the president of the company and worked with many of their staff. Thanks for the great videos -- I really enjoy them.

That was like watching a horror movie. Dude, old tech was noisy, that was the beauty of the old peripherals. After a while those horrible sounds, as one called it, was a symphony of success. Thanks for posting.

I did the composite mod as a teen. Got the board mail order from an ad in one of the CoCo magazines. Getting up the courage to break the warranty void seal was the hardest part of the job.

I am looking forward to seeing more on this one.

It's an early CoCo 1, retrofit with the 'melted' keyboard from the early CoCo 2. Later CoCo 1 cases had the Radio Shack badge centered instead of off to the left, and lacked the RAM badge. The original CoCo 1 boards could only support 4 or 16K of RAM, but were upgradable to 64K with a hardware modification. I got my 4K CoCo in the summer of 1981, and upgraded it to 16K myself with 8 DRAM chips bought off the rack at Radio Shack. I took it to a local Shack (actually an independent dealer, as in the sticker on this computer) to have it upgraded to 64K, since at the time (I was in Junior High) I was a bit leery of attempting the mods myself. I'm glad now that I did, since they put the official 64K badge on it, which I now gather is a bit uncommon. They also added the Extended Color BASIC ROM at that time. There were many articles about how to do the mod yourself, and the lack of a 64K badge suggests that this upgrade may have been a DIY job. Later CoCo 1 systems were sold as 32K machines, but most if not all of them used 64K chips, some of which may have been 'half-bad', ie, had bit errors in the upper bank. Even with a full 64K of RAM, the CoCo 1/2 usually only has the lower 32K active. However, it is possible to copy the contents of the ROMs into RAM and put the machine in all-RAM mode. The OS-9 operating system requires 64K and only uses the disk 1.1 ROM to boot. Another commenter noted that the early Multi-Pak Interface (MPI) didn't support software switching. I don't recall ever hearing that before, though my MPI was a later one, matching the CoCo 2/3 case. (Indeed, the manual is archived online, and software selection has always been a feature.) However, the early MPI had a problem with address decoding in the PAL chips on it that made it subtly incompatible with the CoCo 3. A revised PAL fixed that problem. There was also a problem with MPIs reliably getting IRQs to the CoCo, but that was only an issue when running OS-9 LII on the CoCo 3. The MPI could, of course, be used to switch between game cartridges, but it was most useful for using multiple hardware controllers. Usually you would plug the disk controller into slot 4, and maybe an RS-232 Pak in slot 3 and an Orchestra-90 or Speech & Sound Pak in slot 2. It was also used for the high res joystick/mouse adapter used by the CoCoMax paint program (largely as a copy protection scheme) so you could use it and the disk drive at the same time. There were quite a few 3rd party hardware expansions that plugged into a CoCo cartridge slot back in the CoCo's heyday, including real-time clocks, speech synthesizers, hard drive controllers, MIDI controllers, and voice recognition systems. Another use for the MPI is that it includes 12V on the expansion bus. The CoCo 1 did as well, but it was removed in the CoCo 2 and 3. The earliest floppy disk controller for the CoCo required this 12V power supply, and so won't work with a later CoCo unless you plug it into an MPI. Interestingly, it is only this early FDC that can easily be modified to work with high-density disk drives, since it has a separate data separator IC. Finally, the MPI was very useful for dumping the contents of ROM Paks onto floppy disk. Then you could play Downland or Dungeons of Daggorath _without_ the cartridge or the MPI if you frequently used disk-based software, which became increasingly common. Looking forward to the full repair on the CoCo.

Yes, the MPI (Multi-Pak Interface) allows you to use multiple cartridges at the same time, which is why it has all that extra support logic in it. The CoCo came with a variety of cartridges you could use with the system. At one time for my MPI, I had a Disto II disk drive controller, a Disto RS-232 Pak, and a Speech/Sound Cartridge plugged in at the same time.

Pretty sure that this one has been retrofitted with the CoCo2 keyboard, every silver CoCo 1 that I've seen had the "Chicklet" keyboard. RadioShack actually sold the CoCo2 keyboard by itself as a hobbyist part, I remember seeing one on the pegboard shelf at the local RadioShack back in the day 😂 There were also late production CoCo 1's that had the CoCo2 keyboard, and the CoCo1 case finished in white/beige instead of silver.

TRS-80s are famous for the silver plated edge connectors corroding quickly. That 3rd party gold plug-on adapter was an attempt to improve things from stock.

Looking forward to the proper repair video!

Many a long year ago, I wrote an interesting program for that computer. It was designed to print text on the high-resolution graphics screen. This was never supported by the hardware. If you had a BASIC program and you wanted text on the graphics screen, you had to use BASIC's drawing commands to draw the letters. I managed to shoe-horn a machine code program into a tiny amount of memory. The character-set table which the program used was longer than the program, by quite a lot. 😄 (2048 bytes RAM for the table, but around a quarter of that for the program). The program was written in assembly code and used the Program Counter Relative instructions so that it could be loaded anywhere in RAM. Usually, I'd clear 6 pages of graphics memory and then use the first four for the high-res graphics screen (it required 4 pages for the full screen) while loading the program into the two "spare" graphics pages. The program had a table with the full 8-bit IBM extended ASCII character set. It allowed you to fully control the cursor, screen clearing, and do advanced stuff such as redefining characters from within the BASIC program, put a cursor on the screen, reverse the video (black on white instead of the default white on black) and more. You got 24 lines by 32 characters per line. The program was accessed with the USR (user) command in BASIC. If you gave the command a number, the lower 8 bits of the number would be used as an index into the character set so you could access all 256 characters that way. If you instead sent a string into the command, it would print whatever was in the string... but it would also interpret control codes as cursor and screen controls and as character redefinition commands. There were escape commands which would access the printable characters stored in the control character locations (0x00-0x1F) so you could still print the entire character set using a string. I gave up working on the program because the COCO was falling out of favour as the IBM compatible computers took over the market, but figuring out how to make the computer "dance to my music" was fun.

That keyboard isn't aftermarket, it's an official upgrade from Radio Shack. I think it shipped on some "CoCo 1.5" computers (same size as the CoCo 1 but had a white case). I think also that the CoCo 1 was originally only upgrade-able to 32K, and so some of those bodge wires were used to get it up to 64K (Which the CoCo 1.5/2 supported natively). The Composite output is not something official, though. Also that multi-pack interface is the 1st generation type, and unfortunately that means that it doesn't have a "software select" mode on later gen multi-pack interfaces, which could be used to support the floppy drive in slot 1 and other packs in slots 2-4 at the same time.

One of the many things I like about your channel is the variety of retro computers/components that you look at. Despite the prevalance of Radio Shack stores, I never saw someone with a CoCo in their home.

I think the wear marks are from where your hands would be to use the cursor keys. Possibly for games.

The first computer I had(well it was the family computer at first) was a breadbox 64. The first computer I remember seeing in school(in '85, I was in the 5th grade) was one of these with the earlier keyboard(keys were flat). It was hooked to an old green monitor and we only had cartridges, but we used it all the time in class.

You mentioned a dealer store. Well, I lived in a town in which the store was a hardware store with a section that served as the Radio Shack store. I imagine that these dealer stores were owned by mom & pop owners that served small towns in which were not located near a big city with a dedicated corporate store like many people would find in the later years of Radio Shack.

Since I grew up with the Coco I'm really looking forward to the repair video!

pencil eraser on the gold plated contacts , but something tells me there is VERY little gold plating on there , as gold does not corrode like that

I'm a long time retro computer fan, my first computer being my Acorn Atom which I built in it's kit form. But have only recently found your channel Adrian. I have however watched many of your videos over the last two weeks and found them to be excellent. I love your style of presentation and your clear explanations. Thank you so much for the excellent videos.

Yes, that is a seal from a medicine vial, such as for insulin.

Nice! Coco I was my first computer so it has a special place in my heart. :-) Like others said, that looks like a 64K bodge near the RAM. I also did that keyboard upgrade. You could get it done at RS, but there were some dealers that sold the upgrade kit and that's what I did - came with the keyboard, the adapter from flex cable to pin connector, and a 6822 to replace one of the 6821s. I don't know why that was required tho. I also don't remember having a bodge from the cable adapter to that test point. I still have mine, and a couple of Coco 2s that dad bought to use at school. He and mom were teachers and at that point the only computers in the schools were in labs. Dad's also has a composite mod, but for some reason it's only monochrome out. BTW, if you ever get a Coco 3 be aware that the early Multi-paks require an upgraded PAL chip. In fact I think it can damage the Coco 3 if you don't have the upgrade. There's at least one guy I've seen on the net selling some Coco upgrades including that chip. I think mine has a damaged PAL anyway and since the upgrade IS backward compatible I've been meaning to pick up one myself. Looking forward to seeing the fixes! Oh, and you can use multiple carts at once tho only one ROM cart at a time. The switch only switches a select line as I recall. But if you have carts that don't have ROMs you can have multiples active at once provided they don't occupy the same address space (memory mapped I/O, so you loose memory to devices). I routinely used my floppy drive (with the ROM selected) with the X-Pad and Real Talker voice synth simultaneously since those had no ROM.

Radio Shack had licensee stores, some of which were completely branded as Radio Shack. If a particular store survived the second bankruptcy, then it was usually or always a licensee instead of a corporate store.

Ex-Cell-O is a company best known for its cold forming machines, and which once made precision grinder spindles.

Oh wow, I played around with one my school had back in the 80's. Looked/felt like super high tech compared to other computers we had.

Memories... i had one from my older brother in 1982-83, after my Timex Sinclair 1000!!! I've made a lot of things with this chicklet coco! Good old time!

I've been to that Radio Shack in Los Alamos in 82-83, and over the years. Used to live in Santa Fe, but had friends and family there. I think the last time I went there was around 2007. 😭

Definitely looking forward to the repair video in the future!

My first computer. Ended up tearing it apart and hanging the PCB on the wall connected to my stereo with the the Audio spectrum analyzer cart. It became a dedicated spectrum analyziner 😂 and I became an Atari fan boy after that 😆

The TRS-80 Color Computer 1 was our family’s first computer, and along with it came a Sinclair ZX 80 and a Timex Sinclair 1000. In hindsight, I think the Sinclair worked fine, but I could never figure out how to use them beyond turning them on. The TRS-80 CoCo 1 (we just called it the “Trash-80”) was great. We did some elementary BASIC programming on it, but even though we had the cable to connect a tape recorder, I could never figure out the commands to make that work, so it regressed (to us) to be a computer that we couldn’t save or load anything on. Recently, I bought a wonderful condition one to use in current day, and this time, I intend to get to use tapes! The first one had a chiclet keyboard, and I made sure the recent one did too.

Played around with a Coco 3 once. The RF signal was so strong I was able to NOT hook my TV up and it had perfect reception.

Inspired by your channel/videos, I dug out the CoCo 2 I got from the flea-market, as I didn't recall which version/model (1, 2, 3) I had. Unfortunately, something was rattling around inside! A quick disassembly in the kitchen later and I found the culprit, a teeny-tiny spring! Pretty sure it wasn't part of the CoCo and just fell in through the vents, but it's very good I checked! Wouldn't want it shorting anything out. Being as it's late at night and I'm not sure where my RF adapter is, I decided not to plug it into the entertainment center for a test. I have a single cartridge for it, one that was in my Commodore collection as an unknown/unlabeled cart that didn't fit any of my Commodores or anything else I had available. Turned out that the blank black cartridge was Project Nebula, and it worked! It's crudely labeled now. 39:26 Man, one of those slots is looking pretty green! Has there been a video on the multi-pak yet? I've seen the CoCo-1 repair video.

As a kid, I had a coco 1 (16k later upgraded to 64k) that I paid radio shack to upgrade the keyboard from the original ‘chiclet’ keyboard to that one.. it was an official RS upgrade you could get. As for the multipack, software could control the address decoding independently for the ROM space ($c000-$feff) and the part of the memory mapped I/o space typically used by disk controllers ($ff40-$ff5f) by storing the appropriate low and high nibbles at $ff7f…. Once software hit that address, the front switch gets deactivated until a reset. Someone will correct me if I’m wrong, but I also feel like it actually let multiple carts share part of the rest of the I/O space at the same time - $ff60-$ff7e maybe?? Early version of the multipack don’t work with the coco 3 without modifications because the control register would ‘ghost’ from $ff7f to $ff9f clobbering new I/O registers (in the GIME Chip) in the coco 3

I had an original CoCo (with an E board) way back. There was a lot of discussion back then about repainting the case to repair those worn spots along the front edge. It was eventually found that a specific car touch-up paint was a perfect match: Mercedes Silver. I've no idea if that same shade is available today. (For anyone who read '80 Micro' magazine in that era, you would remember that the regular 'Gamers Cafe' column introduced a character called Mercedes Silver.)

The multipak is manual and Electronic device to swich 1,2,3,4 with pokes, Keyboard is coco 2, first series, The wear on the case is due to the chiclet keyboard that was wider and better aligns with the markings.

0:25 - Not a Walmart pillow. You got upgraded to the premium Target house brand pillow packaging. LOL

The Room Essentials brand comes from Target, not Wal-Mart. Those pillows cost a bit more than $2 but they're still cheaper (and more reusable) than most packing material.

I'm gonna say those wear marks are due to gaming because that's where the arrow keys are.

It is easy to tap a composite signal directly from the input to the modulator. Not great, but good enough for troubleshooting. It can be improved with the simple mods usually done on Sinclair Spectrums or Atari (using a 100uF capacitor or a transistor). You were lucky to get that a fancier mod that is getting the signal from the MC1372.

That was really interesting to listen to and watch, particularly as I used to own a CoCo variant: a Dragon 32 🙂

This is awesome. My first computer was a CoCo1... circa 1982 or so. I think the keyboard is probably a mod, in addition to the extra RAM and the video mod. Mine came with a chiclet keyboard.

After you opened the case I kind of expected to see a little garage mouse looking back up at you :)

I honestly cant wait for the repair video !

Check out those ceramic RAM chips! And love the composite mod. I bet the gator clip was used so consumers could fit it without soldering

If I remember correctly the graphic chip does not require a working cpu to display data. The GPU just scans a section of ram and sets the pixel color to the value in ram. What you are seeing on the display is essentially the power up random values of the ram. This is set up using a dual port scheme so the gpu and cpu can access the same ram at the same time. (different clock phase though). I would say the cpu is not running or does not have access to the monitor rom. If it has been modified the address bank select could be messed up to use a custom boot/monitor rom in a cartridge instead of the onboard oem one.

First time I see the insides of this computer. I think U11 to the left of the RAM bank is an LS138 3-8 decoder he had to mod for the ram upgrade. Those resistors look like 4k7 pull-up resistors. The only reason he would've upgraded that computer, would be to play games.

No one ever really used the 1,2,3,4 switch on the MPI as the slots were software selectable. So, for example, you could have a disk based terminal emulator load from disk, and internally the software could select back and forth between the disk controller cartridge and the RS-232 cartridge for network access along with disk access. So it was basically 4 expansion slots of which only one could be active at any moment, but could easily switch if needed.

18:24 New catchphrase? "DeoxIT that Socket!"

OH, That PATROLMAN radio in the back of your table ! 🤖

Definitely an aftermarket keyboard - original keyboards on the COCO 1 were the chicklet square keys, one of my HS friends had that model and he typed a lot of programs in somehow - one of the smartest kids I ever knew, was doing assembly programming in grade 9. I started with a 16k extended color basic coco 2 t hat we upgraded to 64k - that little machine is pretty much responsible for my career in IT.

This was my first computer in 1981 with the chicklet keyboard (absolute garbage keyboard, and I tried learning touch typing on it... ugh). For as terrible as it was, I still loved it. That machine was magic to a 10 year old. Those wear marks look like they came from using the arrow keys; I used to rest my hands in exactly those spots playing games.

I worked in corporately owned Radio Shack in the early nineties, there was a DBA Radio Shack a few towns over. It was owned by a local man and he did electronics repairs and sold Radio Shack merchandise. I think that the privately owned store dated back to the 60s.

The orange & green garbled screen can happen when the computer isn't reading the ROM chip, but can be caused by other things too of course. I had something similar on a Dragon 32 I bought last year which I solved by reseating the ROM chip, cleaning both the chip & socket in the process, as well as using the equivalent of deoxit on the power switch and switching on/off several times. Not sure which of those tasks cured it, but it took a few presses of the on/off switch for the garbled screen to finally disappear and BASIC to boot. It's been fine ever since though.

The old TRS-80 edge card connectors for the expansions were just tinned copper. And they would oxidize quite badly. So many kits were sold that had a gold plated connector that you could solder right onto the existing edge card connector. I have several old TRS-80's in my possession that have had this modification done. I personally never had an issue back in the 80's, but then again, i never used the "eraser trick." The eraser trick was to use a pencil eraser to "clean" the connector. This was bad because not only was it too abrasive, the rubber eraser contained sulfur, which causes more corrosion to happen. Your best bet was an actual contact cleaner or just re-seat the connector several times to allow the contact fingers to wipe the oxide away.

Cool, a rare third party disk drive for the CoCo! The official RadioShack part for the CoCo1 is the same as a TRS-80 Model I drive, single sided. The CoCo2 ones were the same, just in an ivory case 😂

Downland is my favorite coco game. Also the basic in the coco was very good compared to other basics of the time.

To clean up the contacts, use PHOSPHORIC ACID. Its a weak acid, like vinegar, but isn't going to eat into the base material.

Radio Shack also had owner owned stores, franchise stores, particularly in small towns.

"PLACE IN BASEMENT" on the top of the box, that is very funny :))

A smaller town that I lived in in the early 2000's didn't have an official Radio Shack per se, it was an audio store which was a licensed Radio Shack reseller as well. I imagine Radio Shack had these types of franchises back in the 1980's as well.

Could try to clean the contacts with a hard tooth brush and some contact cleaner, then reflow the soldering, with flux, and then clean again with contact cleaner the residual flux....

I had a CoCo 1 initially then a CoCo 3 back in the day. My CoCo 1 had 64K, switchable IRQ. Needed the IRQ mod for modems as Tandy/Radio Shack messed up in the PAL mod. Power led. My CoCo 3 MPI was switchable so older hardware would work as some addresses were blocked. My CoCo had power leds at the front. I wired them to the 5V and 12V lines as a diagnostic aid. I had an HJL aftermarket keyboard in my CoCo 1 and transferred it to the CoCo 3. Looks like it’s not executing code, thought the 6883 was bad but they do run warm. Wonder if it’s a PIA (6821/6822)? I did have a 6883 fail with flashing bars but your display looks like it’s not doing anything or it’s running but not able to execute ROM code.

The dealer network still exists. There is one dealer about forty miles from where I live.

Hey Adrian, use a pencil eraser on the corroded edge connector contacts. It's very effective, and it doesn't trash the connector like a dremel would.

Looking at that wear pattern, the user might have had a hand condition that prevented using some fingers. I have Dupuytren's in my hands that makes my pinkie fingers useless so my hands are at the same position as the wear marks. Just a theory. It's great seeing a CoCo again, I had one in my teen years and haven't seen one since.

Remex was a big manufacturer of paper and mylar punch tape readers and printing (punching) machines used on computers and industrial machinery from the 1960's to the early 70's.

Great video! Love to see the earlier models with the K RAM Badge and the logo emblem on the left.

for the gold contacts, start with contact cleaner.. then use an eraser. worst case, the fiberglass pencil. Def avoid strong abrasives.

The wear pattern suggests heavy arrow key use ;)

"Dunno what this red wire is here so I'm just gonna cut it off..."

That's a CoCo II keyboard. The final keyboard for CoCo III had clustered arrow keys and some function keys. I don't remember the SAM chip running that hot. I'd check the CPU. That's a "Remex" drive. I had some of them but don't think it was that model. I think those mods around the 6820 are related to the 64k RAM upgrade. 32k was the max supported but with bank switching you could get to the rest.

Doing all of the home modifications was very common on the Colour Computer, especially the CoCo1. That is the melty keyboard which came on the later run of the CoCo1 and early run of the CoCo2. I would guess the mod at the keyboard ribbon might be the lower case mod.

22:56 I'm guessing the wear mark there on the left was due to them using the up/down arrow keys possibly in games? The left/right ones are on the far right of the keyboard as well.

I'm not sure if anyone else has pointed this out yet, but I can explain the wear marks being off to the side. That's where the arrow keys are! If you were playing a lot of games on the system but didn't have a joystick, then your hands would probably be resting in just those spots to use the arrow keys.

@16:29 If nobody mentioned it yet, that SAM chip typically gets very hot, as I recall. It even happened on the CoCo 2. I think with the CoCo 3 it was integrated into the GIME chip which ran much cooler--as I recall.

Hi Adrian! The pattern on the screen may be due to bad lower ram or most probably bad roms. Try the putting in another set and see if that fixes the problem.

I see that you finally turned the Eyoyo upside down! I did that as soon as I got it. It makes it much easier to access the inputs.

Most of those bodges would be for the factory 64k upgrade. That old of a board didn't support 64k directly- wonder if it's got rev F or ET on it. The long red wire to the keyboard interposer is to connect the CoCo 2 keyboard to that older CoCo 1 motherboard, it provides pullup via the resistor pack on the interposer board. The 6822 was also used for the CoCo 2 keyboard as it was a better match to the impedance of that keyboard. Normally the first CoCo 1 keyboard used a 6821. Under the cardboard is just an AC transformer. The 6883's tended to run hot. You can use multiple carts at the same time in the multi-pak as long as they decode to different address ranges (disk drive and RS232 for example) but the slot is software-selectable so it's possible to use multiple same-type carts (multiple disk controllers, for instance, under OS/9)

if you write a basic program that increments a variable from 0 to 255 and you poke that number to every address from 0 to 65535 the computer goes nuts Use to do that to these when they were on display in Radio Shack stores..... 35 years ago...

Bought at a 22-A store... and serviced at a 40- center (of which I used to work at one) :D

Definitely a lot to work on. Looking forward to your next video. Thanks for sharing

My first computer was the 64k version. I wrote a payroll program using the cassette deck for storage. When I changed jobs I ran the spreadsheet cartridge and ran a small college's budget. It definitely would have had the chicklet keyboard. While it was insanely slow running the budget showing the school president how much faster this was than hand calculating changes that summer the school bought its firs XT, and a very early KMS Laser printer called the KISS and yes it stood for keep it simple stupid.

You can use an electric tooth brush on the gold contacts, with some IPA or something like that. It'll have a very fine abrasive action. Just don't use an old one if you don't want the thing to smell like bad mouth smell... use a new one. They don't cost so much.

Packing tape residue can be removed with Bestine rubber cement thinner and an artist's spatula. Generic Bestine is sold as simply heptane. Bestine sells an oilcan-like applicator that you kind of need in order to use the stuff. Also good for price labels and other stickers as well. Probably not good to get on your bare skin though, it evaporates pretty quickly and probably not as bad to be around as acetone. - long time watcher/first time commenter. P.S. - I'd test it on the plastic first but in my experience the stuff is not very reactive unless you take a match to it.

The odd wear pattern on the paint comes from someone playing games (the up/down keys are on the extreme left of the case while the left/right are on the opposite side). Tandy/Radio Shack had a habit of upgrading these machines late in their production run; the earliest CoCos had 4K of RAM and that atrocious chicklet keyboard. When the CoCo2 came out with its 16K of RAM and this improved keyboard you have, the new production CoCos (co-existing on the market with the CoCo2) got the same RAM/keyboard upgrades from the factory. Similarly, when the CoCo3 was introduced, the RAM capacity was bumped to 64K and that great keyboard also came along with it; these upgrades also made their way onto the late-era CoCo2s still being sold. There were also aftermarket keyboard modules sold, but they look nothing like this. I've heard that Radio Shack may have offered keyboard upgrades for original CoCos to this model, but I'm personally not certain. These were very common hobbyist computers for tinkerers not concerned with gaming, so hacking them was very common. You'll probably find the composite mod documented, if not sold in magazines of the era. I recall one of the magazine covers showing the machine with the top off and someone taking an ugly cheap old soldering iron to it; that always stuck with me because I don't remember any other magazines being so brazen about warranty voiding.

Cool setup, can't wait to see you get it working.

Great video. Maybe try a brush on gold plating solution? You don't need to soak it and it should adhere to copper fairly easily.

The screen pattern on power-on looks similar to what I see in the XRoar CoCo emulator when I don't provide a ROM image. You may have bad ROMs in the thing.

i love that cat pillow

cuetips and a little braso on each pin. one at a time. like instead of trying to scrub over the hole thing. just do each pin one at a time.

4 carts on the coco... or 4 cards with interrupts... cards that fit the height :) that could be useful for homebrew full length bus cards.... i bet you could use multiple carts on there at the same time if you remove and terminate the switch? i was saying prolly an interrupt vector or something on all of the cards, or on the board, maybe modded on top with the transceiver ; perhaps some other logic chip. point is, as long as those cards point out to address and or the data of another card, and that card knows where to point, ie, point it either to another card or the bus, you can run all 4 of those at once. you just need some type of controller to do it, like a eeprom programmed to point and listen. youd prolly want some type of a check, those cards arent present, ok, well back to the bus.

Just use the contact cleaner to remove the sticky goo from the decomposing feet and the packing tape, works better than WD-40 and doesn't leave a smell or residue.

Adrian! I that keyboard is the one that belongs in the Coco2, which is my first computer and I still have it. Incidentally, my keyboard broke and it was replaced by Radio Shack with the later tall key design. If you want a OG keyboard for that, I'd love to have yours to make mine original and I'd buy you an OG keyboard and swap it if you are interested. I have a nice Coco Collection, as it was my first and only computer in the house until I replaced it with a 1000HX. My Coco collection consists of. Coco2 64k, 3-512k, Coco2 type Multi-Pak Interface, FD-501 single drive, 2x deluxe joystick, Electronic Book, Kaola Pad, CCR 82 cassette, RS-232 pack, Orchestra 90, modem pak(cant remember model), DCM3 modem, OG Dust covers for disk drive and computer, DMP-130 printer, Audio Spectrum Analyzer, and a good mix of Cassette, Disk, and ROM pack games. I'm probably forgetting a good bit too. I even have the official RS store demo on disk for the coco at Christmas and some others. When I start to dig this all back out again (right now, I'm on a bit of an apple ii kick), I'll upload the demo to archive.org if it does not exist. I really want a 2nd drive for my FD-501. If anyone knows the mechanism number, can you please share it? I'd have to dig mine out, but I'd like to start the search. If you know of one for sale, please let me know. IT looks like a Tandon TM-65 sans obnoxious door lever. I really want it to be period correct and match. Edit-about dealer stores - that is all that is left in 2022, and I'm lucky to still have one near my parents house in PA.