Monitor Checkup
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Power Supply
Game Overview
PCB Damage
Coin Door
Initial Inspection
Monitor Checkup
Logic Boards


The first thing I needed to do was figure out what was wrong with this machine.  At first I tried adjusting the vertical/horizontal hold in hopes that the seller didn't know any better.  This didn't work and I never saw anything remotely similar to an object from the game.

I pulled the board set and visually examined it.  I tried to identify as many IC's as I could and check for any obvious burn marks for burned components.  At this point I noticed that one IC had the edge chipped off.  I didn't think much at first but a further examination revealed that a gold lead/trace was broken when the IC was chipped.  By looking carefully at the board I realized that this IC was definitely EPROM.

Since I now suspected the board set was bad, I wanted to verify that the monitor was good.  I wanted to at least rule something out!  I decided to connect a laptop computer to the monitor.  Luckily I had a SVGA to composite converter lying around.  On the front of the monitor is a 12 pin molex connector that provides power and a composite signal.  After some careful analysis of the connector, I wired up the converter.  A few minutes later I had the laptop connected to the converter, the converter connected to the Space Invaders monitor and the MS-DOS prompt showing brightly in my cabinet!  What a relief it was to know that at least the monitor works!  I took this opportunity to adjust the contrast, brightness and vertical/horizontal hold.

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Monitor board and tube.

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The connector with blue wires (in the back on the right) is where the composite signal and voltage comes in



Second Chance Arcade