> good protection on the pin. If a "direct" path, I thought it more
> likely the power supply may be getting corrupted (i.e. if the HV
> and PIC circuits are sharing power+ground)

That was an early suspect and the HT was put on its own battery.
As that battery is switched via the spark relay there is no direct
connection between the HT and the PIC board. The most recent
modification was to put the two in separate metal boxes. The only
connection is a round trip from the HT battery (+ and -) through
the relay

> judging from the time Joe has spent debugging already seems to
> indicate something a little less "obvious")

Yes. What is so frustrating is that so many things have been tried
yet not even accidental dumb luck has made any improvement

Joe
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