As I remember, there was a thread recently about moisture or
liquid level sensing. Well, design note in March 30, 2000
issue of EDN mag describes use of a xtal at the bottom of a
container of liquid - the frequency changes in relation to
depth, ie, pressure. Other than that, few details are given,
such as freq variation vs depth, how liquid temperature may
be compensated, etc. But interesting ....

regards,
- Dan Michaels
Oricom Technologies
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