Re: Gottlieb problems

From:

http://www.pinrepair.com/sys3/

http://www.pinrepair.com/sys3/#cpu

"One solution to this problem is to install a .1 mfd 50 volt non-
polarized ceramic capacitor from U1 pin 40 (reset) on the CPU (A1)
board to ground. If you are paranoid about soldering on the CPU board,
the reset is also connected to connector P7 pin 1 (unused, for serial
printer adapter) on the upper right side of the board. P7 pin 23 is a
ground. So female .093" Molex connector pins can be soldered directly
to the legs of the .1 mfd cap, with heat shrink tubing on the exposed
cap leads. Then this cap connector an be plugged directly into P7 pin
1 and pin 23(top row-first and last pins). Leave the leads long enough
to bend the body of the cap over the top of the connector so it would
be out of harm's way.

The problem with the capacitor solution is this is not really fixing
the problem. It is enabling the WDOG inhibit circuit (A1P1). A better
approach is to find the actual fault. Also sometimes the capacitor
will not solve the power-on garbage problem, but sometimes it will. It
can work flawlessly, or it can work intermittently with this
modification"

I got my cap from Ed at GPE. (along with tons of other parts) I did
this on shaq after I had good 5v, rebuilt the DMD board, changed the
lithium to offboard, changed the 5v cap in the cabinet, etc. I can
send a photo of my placement if you like. Boots perfectly every time
now. Before I had to turn down the 5v and turn it back up again.

Chris

On Feb 20, 12:47 pm, black.ma...@xxxxxxxxx wrote:

What do you mean by doing the Capacitor hack?

.

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