Atari Gravitar Restoration 3 FINAL

A video game arcade cabinet, also known as a video arcade machine or video coin-op, is the housing within which a video arcade game's hardware resides. Most cabinets designed since the 1990's conform to the JAMMA wiring standard.

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The Arcade Blogger
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Atari Gravitar Restoration 3 FINAL

Post by The Arcade Blogger »

So we’re in the home straight here with the Gravitar. Not much left to do, but I wanted to document these last bits here on the blog.
So I know what you’re thinking. The featured image is of a Space Duel, not a Gravitar right? You are correct. But there are reasons for that – read on to find out!
So in Part 2 of the restoration the cab was in the house and we were making good progress on rebuilding the Gravitar. Here’s the final stages for you:
ImageThe coin door was replaced as this was the state the old one was in. No going back from there I think. The new door is behind, with parts from a donor door that I had lying aroundImageThe coin door wiring needed a few repairs, before I could hook up my bulbsImageThink I mentioned previously that I had completely rebuilt the WG6100 monitor. Here’s the bare chassis before repopulating itImageBit of a side note while I’m here – I noticed a jitter on the screen when I plugged it in, and decided to replace all the frame transistors to see if that would fix it. On removing the old ones, I noticed one of the sockets was disintegrating, resulting in a short from one of the transistors to the frame. After replacement, the image is rock solid. A good result!Next up was reinstalling the cleaned up wiring loom, coin box, power supply, coin door, PCBs and monitor:
ImageHere’s the power block. All restored with new “Big Blue” capacitor and fusesImagePCBs, loom, speaker, coin door and coin box all inImageAnd finally, the monitor was dropped in at the top. Looking good!A good hour was spent doing this – it is worth being methodical about this, it’s very easy to forget to connect something. Take one job at a time – I tend to work from the base of the cabinet upwards. After a final flight check and a double-check that everything was as it should be, it was time for the big switch on:
ImageGravitar from the leftImageAnd the right!There was a small issue though – I had half the sounds on the game missing for some reason. So the PCB needed to go off for repair.
But here’s the twist – I had a Space Duel kit. Space Duel shares much of the power schematic and harness of Gravitar, so in theory it’s a simple case of swapping out the marquee, control panel and PCB. So I figured I’d do that – at least I’d have something to play while the PCB was at the repair shop.
You’ll also notice that there was no marquee light. The reason for this is the incompatibility of the ballast in my US cab, with UK electrics. I won’t go into detail, but suffice to say, dropping a native UK fluorescent bulb into a US setup will result in an instantly blown bulb! There’s couple of ways of solving this problem, one of which of course would be to swap out the ballast with a UK one. They aren’t particularly cheap, and I wanted to experiment a little with an LED solution, which would be handy for future reference:
ImageIt’s a pretty simple conversion. In short, you need to completely bypass the original ballast and starter motor and wire live to one end, and neutral to the other. We can keep the existing lamp holderImageAnd here’s our new LED strip. It looks exactly like a flourescent bulb, but with low heat LEDs! I ordered this from a Chinese eBay seller for the princely sum of £7 shipped! It’s a nice quality product, and arrived in about a week as I recall.ImageDropped in the Space Duel marquee – perfect. Just the right amount of glow, and no evidence of LED “Dotting” that you might expect. Very pleased with that, and very handy to know for future restorationsSo here we are – the finished article. One Atari Gravitar, with a Space Duel kit installed inside:
ImageIt looks great! The artwork really popsImageHere’s the right hand side. As a two player game, Space Duel works really well. The cab is nice and wide to accommodate both players without any issuesImageYou can see just how tall these late Atari vector cabinets areImageI’m particularly pleased with how the front black vinyl cleaned up without having to be replaced. You should be able to make out that I made up a matt black kick plate to cover up the cracking at the bottom. It tidies it up really well. The coin door was completely replacedImageAnd here’s a quick before/after shot. I reckon that’s a job well doneSo there you have it. I’m trying to work out how best to mount a credit switch, as Space Duel‘s “freeplay” mode doesn’t show some of the attract sequences, and just sits on a static screen waiting for the player to start, which I find super annoying. I might also revisit the t-molding. The standard size doesn’t quite fit, as the cab has swollen with age – nothing bad. It is still solid as you can see, but I suspect the particle board has drawn in moisture over the years – probably down to being stored somewhere cold. Slightly wider t-molding is available which would sort that, so I may order some and replace what I have on there.
ImageHere’s the cab in situ in the loft arcade to give you a sense of scale:And finally, since I wrote this piece, the Gravitar board is back all fixed. I’ve reinstalled the kit, and here she is:
ImageThe completed Gravitar!Right, I’m off to play some vector games! If you want to look back at the complete restoration of this cabinet, go here.
Thanks as always for reading this week.
Tony
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