Midway Space Invaders Monitor Issue

ArcadeTechGW

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Donor 5 years: 2012, 2022-2025
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I helped a customer find this game. It's a little tired, a Midway Space Invaders.

I cleaned out the cobwebs and dust, and tried to power it up. I get a loud hum (I guess it doesn't know the words). After 30 seconds of this, I smelled something that didn't smell right (something was starting to go), and I killed the power.

Opening up the coin door, I think I'm working with a Motorola black and white monitor. The horizontal deflection pot is in two pieces, and the flyback HV lead is covered with black goo, like a flyback volcano.

I figure the monitor is pretty much toast - I get no image.

So, here is the question in the sad tale - can I retrofit a WGF1979-SDSS39J to this application? Has anyone accomplished this feat? If so, any tips to make it work quickly?

The customer is less than happy (surprise), and I'm trying to get this flipped quickly.
 
Sounds like every other b&w monitor out there...nothing out of the ordinary there. The horizontal deflection coil (not pot), as long as its in one continuous piece...should be ok even if its broken.

Turn it off...and move around all the pots on the back of the chassis to clean them. (dont mess with the coil) Unplug all the plugs off the boardset and then turn it back on and bring up the brightness...if you get a white raster, the monitor is prob OK.

Chances are what you smelled burning are the diodes on the corner of the power supply near the black plug. Note that the larger ones test open even though they're ok, but usually the smaller diodes there will burn up. Bob Roberts has a rebuild kit but the smaller diodes I believe are 1n4007 you can get from radio shack.

Also clean up the fuses on the power brick (unplug the game first) and make sure they're the right values.
 
Thanks

Thanks for the tips. I'll give that a go.

I noticed that the ground was off the tube, so I'll re-adjust that into position, and try again. Given the buzz I heard when I turned the game on for the first time, I think I have blown diodes in the PS. I have the PS test procedure, and will get to it.
 
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