Jinx wrote...

>It's a good idea of yours to buffer the PIC with gates. I've got
>a few HC244s and 4049/4050s. For the sake of a few cents
>it's worth doing

4049/4050 running at 5V aren't very beefy.  Run 'em at 15V and they
can whump out some juice, but at 5V, HC244 would be better I think.
As a disclaimer, I'm doing some guessing here not having the
datasheets before me; check it out.  Another possibility for this
might be some kind of "clock line driver" chip.

>Not interested in repairs - this unit is installed up a 30ft
>concrete column. It goes in, it stays in

Whoa!  Concrete?  Hmmm.  Yeah, use big diodes.  :)

>(btw, thanks for spelling Schottky correctly -

Glad I succeeded in that.  Had to type it a couple different ways to
see which one looked right...

>Thanks again. I'll post circuit and results when done, promise.

Sounds like you're good to go.  Let me know if I can do anything more.

Dave

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