Possibly your PIC can write to an unused audio track using a cheap 14.4 modem.
Then use the same modem to retrieve the data.  Position data can be as simple as
*1234   where * is the delimiter, 1234 is the position data.

Feel free to e-mail me if I can be of further assistance

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Gus Calabrese    Joanne Yamaguchi      WFT Electronics        omegadogs
4337 Raleigh Street      Denver, CO 80212
303 964-9670......voicemail        fax  (see below)
mailto:wft@frii.com       http://www.omegadogs.com     http://www.wftelectronics.com
 cell phone  720 987-6543 (like a rocket countdown)


fax   please do not send long faxes, they are auto-forwarded and the
resolution is not particularly good.  801 409 4969

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