720 Restoration

benazeer

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I'm new to the world of arcade games, and came into possession of a 720 this week. The previous owner inherited it from a deceased friend, and says it was in good working order when she received it. Unfortunately, her house flooded, and now the game does not turn on.

I'm hoping that in terms of electronics, it's just the power supply that's fried. The previous owner can't say how high the water line got, so we have no idea if the video PCB was immersed. Step one in the restoration project will be pulling out the power assembly and testing the components, replacing as necessary. (Unless someone knows of a good drop-in replacement for the entire assembly?)

The cab is pretty beat up though, so while I'm at it, I'm planning on sanding, repainting, replacing the artwork, etc. I'd like to use vinyl instead of painting the cab, but it seems that ThisOldGame no longer has the reflective grey vinyl on their website. I shot them an email, but in case they don't stock it at all anymore, does anyone have recommendations for where to find a similar color?

Any other advice from game restoration veterans?



 
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Yay! You made it! Welcome aboard. :D

That doesn't look so bad from the photos. Is the particle board swollen? (it acts just like a dry sponge when it gets wet) How high is the swelling?

My personal style is "gameplay first, then cabinet work". As long as the cabinet is stable/safe, I like to get the game working, then worry about restoring the cabinet. Others may (WILL) disagree.

Electronics wise....
That looks like a switcher. It may not like being powered without a load. So leave it in the game and double check the wiring to make sure it's all connected correctly, then power it up. Measure the supply voltages. There should be test points on the boards. Make sure to measure on the boards...you'll get I*R drop in the wiring and especially across the edge connectors. If your voltages are low/non-existent, then backtrack all the way to the transformer until you find the problem components. Note that the power supply is most easily considered a replacable unit. Linear supplies are worth rebuilding. But switchers are pretty generic and cheap and easy to find new replacements.

For the PCBs....flood damage can be nasty. Lots of particles and electolytes to get stuck under components. They should probably be wet-cleaned. How you do that really depends on what components are on the board. Coils, wires, and especially DIP switches don't like water. Nor do EPROM labels and socketed parts. But wet DIP switches are almost always doomed. I don't have any system 2 games, so I don't know what's there exactly. Others will have to help on that.

Good luck!

PS. Do you have the back door for the game? It really doesn't look like the game got wet inside. (??) It might have been pressure sealed by the swelling wood if the water rose slowly enough. I would expect to see a high tide mark in all that dust otherwise. Of course you may be able to see things that the photos don't show.
 
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Welcome man...and thanks for taking this on. I'm always happy to hear of another 720 being saved. You're in the right place if you're looking for restoration help.

There are plenty of good 720 restorations you can use for reference. I link my own, and a few others' which are much better, on my site. There is also a joystick help page and a 720 registry where we're attempting to record as many working 720s as possible. How much info is given, or whether to add yours or not, is 100% voluntary of course, but I always appreciate it.

As to the specific vinyl question, the Ataricade 720 was restored before ThisOldGame ever got and pre-cut vinyl, so it is certainly possible to order good matches from regular vinyl vendors, but you usually have to get a roll...not something pre-cut.

The other, less authentic method is simply to refinish and paint the cabinet a similar color. That's how I did my 720 years ago...but that was long before I found this forum, or knew anything about the hobby.

Good luck and keep us posted.
 
Yay! You made it! Welcome aboard. :D

Never say I don't follow your advice :)

That doesn't look so bad from the photos. Is the particle board swollen? (it acts just like a dry sponge when it gets wet) How high is the swelling?

I don't see any signs of swelling, but then again, I didn't spend too much time examining it since it's covered top to bottom with cat hair. I guess I lied about first order of business being diagnostics on the power supply. Plan for this afternoon is to dose myself up on Zyrtec and give the thing a thorough cleaning.

Electronics wise....
That looks like a switcher. It may not like being powered without a load. So leave it in the game and double check the wiring to make sure it's all connected correctly, then power it up.

You are correct, sir, it is a switcher. I've got some 2W resistors kicking around that I could use to make up a dummy load, but if you say it's best to leave it in, I'll defer to your experience. But you get to explain to my partner why I need to turn the living room into an EE lab :)

Measure the supply voltages. There should be test points on the boards. Make sure to measure on the boards...you'll get I*R drop in the wiring and especially across the edge connectors. If your voltages are low/non-existent, then backtrack all the way to the transformer until you find the problem components. Note that the power supply is most easily considered a replacable unit. Linear supplies are worth rebuilding. But switchers are pretty generic and cheap and easy to find new replacements.

Chris, darling, I do know enough to backtrack to problem components. Give me some credit here :p


For the PCBs....flood damage can be nasty. Lots of particles and electolytes to get stuck under components. They should probably be wet-cleaned. How you do that really depends on what components are on the board. Coils, wires, and especially DIP switches don't like water. Nor do EPROM labels and socketed parts. But wet DIP switches are almost always doomed. I don't have any system 2 games, so I don't know what's there exactly. Others will have to help on that.

No coils, wires, DIPs, or EPROMs at the bottom of the video card. It's mostly resistors and caps, which are easy enough to replace, and ICs which might be easy? I don't know how hard it is to find replacements for those, but no point worrying about it until I've got a functional power supply.

PS. Do you have the back door for the game? It really doesn't look like the game got wet inside. (??) It might have been pressure sealed by the swelling wood if the water rose slowly enough. I would expect to see a high tide mark in all that dust otherwise. Of course you may be able to see things that the photos don't show.

Nope, no back door, and no high tide line. I was told the water was really deep, but looking at the game now, I'm not buying it.



Good luck and keep us posted.


Thanks! Will do.
 
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