Rescue 911
Gottlieb, 1994So i installed the components from ed and I am making progress! The power supply works. I adjusted to 5.0volts.
However:
- the board with the battery led is blinking, it looks like it's on but it's blinking
- the top left board the led is not on. But I did catch it on steady once. Power at the aux sound board p1 connector is as followes.
1:5.01v
2:11.90v
3:-12.01v
4:.05v
5:.05v
6:no wire
7:3.69v
8:.05v ( it's a jumper to 5 pin)
0please advise
Its been a while since I worked with Gottlieb System 3 but as I recall, a common failure which would leave your game dead, but an LED would be blinking is a bad U8 PAL on the Dot Matrix Controller PCB. With a bad one, the CPU can't access the on board ram and then just stops never finishing boot or displaying anything at all. That's the board in the upper right corner.
The boards in the upper left are your sound and speech boards. The sound board has its own processor and I think it should be blinking also showing life.
Its going to be tough to diagnose without a good game to swap suspect boards into. Especially since all boards may have been fed more than 5.25VDC.
Unplug the power connector to all of the boards except for the CPU (bottom right), the DMD driver board (top right), and the display and ribbon cables going to the display. When booted up, these two boards will flash back and forth showing communication. The CPU needs the DMD board to boot properly.
If you don't get these two to boot, it will then be time to take some more readings of voltages at these two boards.
This is a great resource too and may help in your troubleshooting/debug effort: http://www.pinwiki.com/wiki/index.php?title=Gottlieb_System_3
Quoted from turbosl2:Ok I will give this a shot. I should note that none of these boards have a blinking LED. They are on solid, except the one in the bottom right that flashed rapidly then a pause.
That is your CPU.... most likely your DMD driver board is whacked out and your CPU is good, but we will need to see the voltages and go from there. The CPU talks to the DMD board and waits for the DMD board to respond. the flashing back and forth shows communication working between both.
If you're getting 5v on the DMD board, the U8 chip is usually the weak link on the DMD board, followed by RAM. I would also suspect the ROM chip in this particular case. After that--you might have to start doing shotgun replacements of other chips.
If you had a known good DMD board, you could easily determine if the problem is isolated on the DMD board, or if there are additional problems on other boards. That would at least save you from having to replace components blindly.
Voltages at the P2 DMD are as follows
1:5v
2:.03v
3:.03v
4:.45v
5:68.4v
6:no wire
7:-119v
8:-107.3
According to the manual you guys sent pin 4 should have 12v volts and I don't have it. What supply's this 12v?
Also, for what it's worth if I unplug the aux power supply the light on my aux sound board goes from not lit to full on.
I am really wondering tho what feeds this 12v that I am missing to the DMD
Quoted from turbosl2:What feeds the 12v to pin 4. I been looking for good schematics but they are hard to find to trace it to pin 4
To the transformer through a8j1 to a12j3 / a12p3 to a12p3 / a12j9
Looks like I forgot to follow-up with the link on what happened with this.
Here is the repair log:
Display Driver Board: 6264 Static RAM (U4), 74HCT08 (U6), U8G PAL (U8). Note: Replacing *only* the U8G chip without replacing the other failed chips first may damage the new U8G chip.
Sound Board: 74HCT374 (A3), 74HC08 (G5), 2x 6116 Static RAM (H2 and H3).
DMD: Large sections were fully lit or fully dark; replaced the DMD.
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Ballston Lake, NY