Over time the lab collection has expanded with donations and the occasional purchase. But in May with class looming the next semester, I had to turn my attention to maintenance. Old computers don’t always stay working ever after being restored to full functionality. During a visit of the IEEE Computer Society student chapter it became apparent that all three systems on this table had problems.
On the left, the Morrow CP/M computer connected to the IBM terminal complained about all its boot floppy disks. It turned out one of the 5.25 inch floppy drives had failed — it no longer span its motor. Fortunately I had a spare drive of the appropriate kind used for the BBC Micro and was able to swap it.
In the center, the Apple II had for some time been displaying intermittent but increasingly common determination to ignore all the keys on one of its input lines, which unfortunately includes both enter and space. During during the visit of the IEEE club a couple of weeks ago that made it impossible to play Oregon Trail and the fault seemed permanent rather than intermittent. Could be a bad connection or a stuck key switch. Removing the cable connecting the keyboard to the computer and cleaning it seems to have fixed the problem, for now at least.
On the right, the Atari VCS suddenly deteriorated, refusing to work with several games and not always generating a picture. Testing it out, most cartridges didn’t work and the ones that did work had a fuzzy picture and were glitching. Also it had reverted to black and white. I took it apart. This is a later model, where the circuit board was shrunk to save money, leaving the woodgrain case mostly empty. (Atari eventually shrank the case too).
There is not very much to go wrong because the Atari has mind-blowingly minimal hardware capabilities, for example just 128 bytes (not kilobytes) of RAM. I cleaned bits of the board with alcohol and removed debris from the cartridge port with compressed air and tweezers. Then I took my can of Deoxit, which can work wonders, and sprayed it into the cartridge port. Then I removed all three chips from their sockets. I sprayed Deoxit into the sockets and around the legs of the chips and replaced them.
Shockingly, it worked. The color was back and the console worked property. Except, there’s a potentiometer (i.e. the round plastic thing in the bottom left) on the circuit board used to adjust the color. I’d turned it up and down – for a while it’s black and white and then colors appear, but as you turn it further the colors change totally. Not just more intense, but complete different colors. As most Atari games use a selection of psychedelic backgrounds for different levels it was hard to know whether the screens I was looking at in PacMan or Superman were supposed to be orange, blue or green. But then I remembered Frogger, and the green border where the frogs live. It turned out to be displaying as orange, but with a little adjustment was a nice bright green.
(The green is actually the same up and down the whole screen, but the camera captured the TV half way through refreshing the screen).
And as a bonus, the Pitfall cartridge I picked up at the Midwest Classic expo now works. It’s referenced in my book, so it’s nice to have one to demonstrate the complexity achieved through ingenious programming tricks later in the trajectory of the VCS.
The next week during lab hours I put it back together and Wyatt Kalmer called by to help fix one of the flaky joysticks it came with. The Atari VCS joysticks are iconic, literally in the sense that the shape is used to represent 1980s videogaming in general. (https://en.wikipedia.org/wiki/Atari_CX40_joystick ) But also bad: they dig into your hands, the fire button is in the wrong place, they are stiff, they are imprecise, and they tend to fail. In this case, the down movement was hit and miss. Opening one up for the first time, I was struck by the weird combination of chunky 1970s construction and extreme cheapness.
By modern standards the circuit board and case are solid and robust, but the design was clearly very cheap by the standards of it’s day. There’s a flimsy plastic collar that pushes down on switches to register your inputs, but the switches themselves are flimsy little metal domes that get pushed down to short out connections the board. Now I know why rival joystick suppliers always boasted about having “microswitches.” The Atari metal caps are held in place by nothing more than a piece of plastic that looks a lot like packing tape.
Over time the tape goes gunky and the switches get a little oxidized and no longer make good connections. So you remove a section of tape, clean around the little metal cap with alcohol and Q tips, and then apply new tape. Conceptually simple but very fiddly – especially as we briefly lost the little metal cap. But in the end, thanks to Wyatt’s patience, victory.
We tried to play Combat to celebrate. This brought a sad discovery. The repaired joystick worked fine, but unfortunately the joystick I thought was good is now having difficulty with the fire button. Apparently the fire button tends to wear down, which I hoped to fix by applying another layer of sticky tape to offset the erosion. Frustratingly, we found that the fire itself button worked fine but the problem came from the cable joining the joystick to the console. A long term solution will require either a new cable, fortunately spare parts are still being manufactured, and probably also a new circuit board for the first joystick. But we found a temporary solution: as the cable works only when pushed in one direction we applied some packing tape to hold it in a tight loop.
We then finished up the lab session with a nice game of Combat played for the first time in this lab with two original Atari joysticks. Both players can now experience an authentically uncomfortable experience. As they used to say on Prairie Home Companion: Duct tape, because in the end all solutions are temporary.
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