[aprssig] Cave Surveying
ve7gdh at rac.ca
Tue Nov 20 21:34:48 EST 2012
Clay AA3JY wrote...
> Some have short memories..but I posted this back in September:
> What is used to help facilitate surveying in cave diving(water
> medium) in north Florida..a Pinger device in the 350hz range.
Could you please give a short description on how the Pinger is
used? I assume the diver / spelunker would have the transmitter.
How does the receiver determine the Pinger's location?
73 es cul - Keith VE7GDH
"I may be lost, but I know exactly where I am!"
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