Tempest: The Perfect Video Arcade Game. Released in 1980 as the first of a handful of Atari Color Vector Graphics machines, this is reported to be one of the most popular collectors items among video arcade game enthusiasts. Keeping a 29+ year old piece of technology running is... challenging.
My machine is actually the 2nd Tempest I've owned. The first one I bought for $50, fixed it up, kept it for about 5 years during my college days and then sold for a reasonable profit. It took a few years before I really missed it. Fortunately opportunity knocked at the right time and I got the 2nd one about twelve years ago for $75.
This second unit was in poorer cosmetic condition than the first but the electronics still worked. Ironically, the X-Y deflection transistors (which are usually the first to blow) are still the originals! They look a bit rusty, but since I installed the LV2000 upgrade kit I have no worries about them burning up. (My 1st machine went through several sets of expensive transistors. Wish the LV2000 was available then!)
The only nagging problem I've had in the past few years is the spinner. The thing was very well designed, except Atari made it with cheap nylon bushings. Once they wear, even a little, the spinner knob will make the characteristic Tempest "Buzzzzz" when you try to spin it fast and the wheel quickly drags to a stop. And if you've ever played Tempest, you will know how important it is to spin fast and accurate. I tried applying heavy grease, but it didn't help one bit.
Last month I pulled the spinner unit out of the console and it sat on my desk for weeks. I wanted to install ball bearings but time constraints prevented me from going to the machine shop and fabricating pillow blocks for them. Every day, though, I'd stare at it, play with it when speaking on the phone, and envision ways to retrofit the bearings.
Then one day (about a week ago now) I grabbed a baggie of assorted ball bearings I had bought on eBay. I had several of the right size: 1/4" inside diameter for the shaft. But looky there! My baggie had a wonderful surprise for me. Bearings with flanged ends! I had no idea such things existed in this small a bearing.
It then took me only a few moments to devise a quick fix for the spinner, which entailed redrilling the 1/4" shaft holes in the frame to fit the 5/8" outside diameter of the bearing. In less than 60 minutes I disassembled the unit, bored holes using a 4-flute 5/8" end mill, cleaned off the oil and reassembled everything.
Best of all, the enlarged holes were the only modification for the retrofit. No changes were necessary to the flywheel, shaft or encoder itself. The flange on the bearing was maybe thrice the thickness of the original nylon bushings but there is still plenty of space between the E-clips on the shaft. Everything fit comfortably.
And the end result? Sweet gameplay control! No Buzzzz noise anymore, and the wheel is so slick it spins for several seconds before coming to a gentle stop. I had to change my gameplay strategy a bit because the spinner was so slippery, but that's all to the better.
Flanged bearings like the ones I used can be bought at McMaster Carr for about $7 each. Try part # 57155K324.
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