It seems like Bob Blick had the best idea for the
cheapest way of measuring water level in a pipe.

There is an application note for the LM3909
that describes a setup (electronic trombone)
whereby a speaker will emit a sound tone at the
resonant frequency of the sound box. I only have
to measure this frequency with a PIC to get the
water level.

I will obviously have to experiment a bit to see
how repeatable and reliable it is.

Thanks Tom, Bob, Clyde, and the other folks who
have helped so far.

--
Friendly Regards

Tjaart van der Walt
mailto:tjaart@wasp.co.za

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