Amiga cleaning time

Northern spirits

Amiga 500 and manuals.

The midsummer night's sun beckoned -- "Take out your Amiga 500 and check for battery leak damage. Do it now." So I did. I covered up the top of the case in this photo to cover a rather diverse gathering of filth. The Amiga 500 manuals are in full color and with lots of technical information. The A1200 ones were unfortunately in grayscale.

Amiga 500 motherboard.

Fat Agnus, Denise, Paula and Gary are still having a party in there! No battery on mobo as far as I can tell. Quite a beautiful board, but I wish the chips had little logos and figures printed on them. As a kid I wanted to do a 3D game where you ran around on a computer chip, meeting its inhabitants, and I remember making something very crude in 3D Construction Kit. Realized that I needed to learn assembler, bought some books, but didn't learn much.

This is... VAAAARTA!.

Oh, there you are you leaking bastard, pissing all over my expansion memory.

Amiga 500 motherboard.

I crazily thought I might be able to simply migrate the socketed trapdoor RAM chips to the empty sockets on mobo if the trapdoor circuit board is done for, but it's a complicated affair. I have a Rev 6A board with a 8371 FAT AGNUS, which apparently is what sits in PAL versions. This Fat Agnus can only address 512kb but you'll notice that it sits in a socket which facilitates upgrade. I mostly use my A1200 with a Blizzard 1220/4 anyways so I'm not gonna bother with the A500. I might use it for testing low end game projects.

Amiga 500 expansion memory battery damage.

Clipped off battery as my soldering iron would not heat up. Scrubbed area with lemon juice as advised elsewhere, but didn't want to overdo it so the damage still looks nasty. The battery only keeps the clock running and isn't needed for the expanded RAM to function however.

Amiga 500 case.

I don't know anything about which chemicals to use when cleaning up plastics, but I did some seemingly successful tests with a window cleaner which contains denatured alcohol... and some perfume! My Amigas had no particular smell though as I do not smoke, nor have I stored them in a mold infested attic or garage. Not going to bother with Retrobright to reverse the tan. Had to be careful with alcohol around the C= label as it takes off the gray.

Mac Games.

When something is less than 2 meters away from you and you still can't find it, you become acutely aware of your lack of omniscience. The RF-Modulator has gone into hiding. I know I've seen it around, but now it's suddenly gone... now when I need it. Indeed, you know the exact feeling.

I did find a couple of Mac games instead. Circa 1995... those were the Mac years for me, though I was still using my A1200 regularly for a few more years. I wonder if I could play these games through a Mac emulator. These are not bad games.

System 7.5 running in Basilisk II.

I downloaded Basilisk II (68k Mac emulator) and got System 7.5 installed on a hard drive file after some trouble (peripheral programs and files were needed). Also, people who upload StuffIt Expander in a stuffit archive can, you know, stuff it (apparently). Oooh, looks like you can paste 64px Desktop Patterns into the selector program, but the images dither into what appears to be a 256 color palette (and not the system one as far as I can tell). Just as I was about to save this palette Basilisk blue-screened Windows 7, so I abandoned the project.

I'm forgetting something... Oh, the games. Well, the CD drive driver won't work in a 64-bit environment, but apparently you can make ISOs and load those. More programs to install and I sort of lost the appetite. Hmm, weren't I doing Amiga things? Right, the search for the RF-Modulator.

Amiga mice.

Maybe I did put some Amiga stuff up on the attic after all?

Found the broken mice! And the culprits >:(

Three Commodore mice and an Atari/Amiga mouse. On a round Commodore mouse, you'll find the screws under the label (which can be carefully removed without damaging or bending it noticeably). Pull back top half (like you load a pistol) to unsnap. The micro switches can be replaced somewhat easily and aren't expensive.

Amiga 1200 case.

The A1200 was quite gunky as well, so I gave it the window cleaner + toothbrush scrub. Only some very subtle white patches around the keyboard holes remain, and that's from the shadows of the keys (yellowing comes from light exposure iirc).

Amiga luxury berth.

With no RF-Mod in sight, I'll just have to let the project rest for a while. Top: A1200 with the lone functioning "Naksha" mouse. Mid: A500 showing its innards. Bottom: Extra drive, Amiga Sampler, 亀の恩返し ウラシマ伝説 (famicom), random 3.5" HDD and dead 2.5" Conner HDD, Game and Watch games (My dad visited Japan when they were still a new thing, came back with DK). DKjr has the score 772 noted on it. I used to open these and replace the levels using overhead film and pen.

Amiga Tank Mouse.

Update! Managed to replace mouse buttons on my original Tank mouse using new Panasonic micro switches. They only have 4 legs and are a bit taller, but the legs can be (un)twisted into place. I had to cut some plastic off the button + rods which meet with the switches. The common 6x6 tactile switches fit, but are too hard/clicky for use in a mouse.


Not finished, but works!


Forgot to turn off edge-improvement on TV, but otherwise I see no notable video signal artefacts. TV scaling makes picture a bit blurry, but on the positive side, it fixes the hires flicker. I have 2+4M or RAM (courtesy of Blizzard 1220). Icon theme is still WIP. Computer reboots in 3 seconds and doesn't touch drive unless I do something or there is a virus doing something (fortunately very unlikely these days).

Amiga 1200

Adventures with "retrobrighting". Before shot. It's easy for a camera to lie about exact hue, but this is the same case as in images above.

Amiga 1200

Results seem to be a mix of the % hydrogen peroxide * sun power * time. Stronger % can be dangerous and even low % stuff gives nasty blisters. Don't dilly-daddle with protection. Can't believe this stuff is used in the hair. I used a mix of 3% wound cleaning HP and 10% hair salon cream (to make it more creamy, mostly). The hair stuff I got came with a bunch of other packages (boosters) aside from the white cream. I tried those (mixed in) on another test surface and they proved destructive to the plastic. Another lesson learned: Apply stuff indoors, wrap out, place on junk table. If you work on the ground outside, dust, bugs, and in my case, red mites, will invade and cause a mess. The red mites can even cause orange stains.

Amiga 1200

Again, as you can see, exact hue depends on camera and lighting. I've done the top case and the arrow keys here. It's strange to see the yellowed keys stand out so much now. Was it really this bad? The keys actually have inverted shadow gradients burned into the sides. Waiting for a proper key-puller. Oh, I did the mice too... well, actually, one was done using...

UV UV-array: UW-1200! 12 for the 12 LEDs and 00 for the 100 Ohm resistors. UW for Ultra Weak. More on that later. I used a generic 5V USB/Charger supply but made the rest. Component tester gave me a 3V drop on LEDs and because I wanted max shine (without killing LEDs) that was (5V-3V) / 0.020mA = 100Ohm (parallel configuration).


I built a reflective house. UV LED light is partially invisible and can apparently be harmful to the eyes as it doesn't trigger blinking/squinting. Better safe than sorry - I pulled the plug on every checkup. After a test run, this device proved to be pretty weak and I believed it didn't actually work at all for a while. I did the mouse cover in the sun instead. Later I noticed a yellow side on the bottom case, and with no sun out, I left it in the UW-1200 overnight. In the morning, the yellow had been purged. I had it standing on its side so it was really close to LEDs. Temp-gun told me the board gets a little warm (+15C), but not the housing/subject (+5C).

Datic Naksha mouse

In 199x, I bought this DATIC Pro (store-demo version) Amiga mouse after having had bad luck with other mice (...I simply didn't know how to clean and repair them). When I opened the box, there was a Naksha logo on the mouse. Never looked into that mystery. It came with a cable extension/adapter, so... maybe an Atari mouse? Regardless, it was a very good mouse for the time. Is. I still use it with my A1200 over 20 years later. I never quite liked laser mice because the lack of momentum when lifting. Judging by the box photo, it was never cream color. This was after the first treatment, I did another one later, in the UW-1200 that by then had re-earned some of my trust.

Art by Arne Niklas Jansson