Re: tech question: 1 farad battery cap failure

Okay, I pulled the board then desoldered the cap. Checked it for
voltage, nil. (well millivolts, almost nil) fo to diode tedt and it
shows "charging" or run up. Looks good. Do the 9 volt battery thing,
Viola, it's holding a charge.

So I guess the charging circitry on the mpu is dead. What would you
gus recommend, troubleshooting the board, or just installing a battery
pack. I am leaning towards the battery pack.

Thanks

jeb

On Oct 15, 6:43 pm, AcePinballRepairs <acepinballrepa...@xxxxxxxxx>
wrote:
On Oct 15, 2:14?pm, "jebsfo...@xxxxxxxxx" <jebsfo...@xxxxxxxxx> wrote:

I have installed a memory cap on my Eight Ball. It had no battery and
the board is suspect. Anyway, the cap will not charge up (no memory)
When I pull the cap back off the board and test it with a dmm, it
shows dead short. Is this normal or should it show resistance, etc.
I guess is all else fails on this mpu, I will install a batterypack.

jeb

You can check the memory cap. Remove it. Take a 9v Battery and hold it
to the cap leads ("+" to "+", "-" to "-") for 5 seconds and remove.
Now measure the cap Voltage. You should have at least a couple of
volts on it. If you have voltage, it's good for the memory use. Note:
the battery may get quite warm in those 5 seconds.

Kirk


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