[aprssig] Cave Surveying

[Steve Noskowicz]

I remembered.  I poked around from that link and that's where/how I got my info.  There are two versions of that article and they both say  1.16 kHz.  A higher freq and some modulation from the TNC ...

If one were to get really aggressive you could have several of these transmitting from above, each from a different GPS receiver and actually send posit data into the cave.  It would only be discreet locations, but location none-the-less.  Translate this to a micro power transmitters on, say 144.39, and the cave radios wouldn't need any special hardware.

Just ideas...

73, Steve, K9DCI  USN (Vet)  MOT (Ret)  Ham (Yet)

--- On Tue, 11/20/12, AA3JY at Winlink.org <AA3JY at Winlink.org> wrote:

> Some have short memories..but I posted this back in September:
> 
> http://www.tapr.org/pipermail/aprssig/2012-September/040466.html
> 
> What is used to help facilitate surveying in cave
> diving(water medium) in north Florida..a Pinger device in
> the 350hz range.
> 
> Clay AA3JY
> NSS-CDS
> NACD