GO7 question

Txny Mxnrxe

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A while back I picked up a Galaga with a GO7 that had a non working chassis. The first thing I did was install a cap kit. I then noticed that I needed to replace the small fuse and the flyback. I replaced the flyback today and for the first time I have gotten some life out of the monitor. When I flip the switch, the screen comes on after a few seconds but the whole screen is green with lines changing between vertical and v-shaped from top to bottom. I have tried two pcbs and the results are the same. The only time I got something different was when I flipped the edge connector on the board and I got a high pitched sound and a faint image of the starfield and ram ok but it was inverted and still under the lines. This is my first machine and I admit I may not have connected everything correctly but I am stumped. Any and all help would be greatly appreciated.
 
1 - sounds like you might have the edge connector on backwards? Either way, take it off and leave it off for now. You can get a picture with it off, but not always with it on.

2 - you should have two connectors that attach to the board - a 3-pin molex for power and a 6-pin molex for video. If those two are attached, you can get a picture on the screen.

3 - it's not uncommon after a cap kit and rebuild to have to readjust the control pots on the monitor to get a good picture. If you get a picture with the edge connector off, take a pic and post it here so we can tell you what control to adjust next.

4 - before you reconnect the edge connector, you need to check the manual's wiring diagram to make sure the wire colors are going to the proper pins on the PCB:

http://arcarc.xmission.com/PDF_Arcade_Bally_Midway/Galaga_Parts_and_Operating_Manual_(Oct_1981).pdf
 
I haven't gotten a picture on the monitor at all. It is the same whether or not the edge connector is plugged in, just lines and a green screen.
 
I haven't gotten a picture on the monitor at all. It is the same whether or not the edge connector is plugged in, just lines and a green screen.

You said you had a starfield and RAM OK, but inverted. That's a picture.

Are you getting proper +5 and +12 at the 3-pin connector to the PCB?
 
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