SPOT tech
SOME technical details for the SPOT watch technology.
Also, Rich Davies – Inside the SPOT watch team on Channel9.
Wikipedia DirectBand
Wikipedia RDS
FM subcarrier decoder kit via mobilewhack.
The connection between ATARI and SPOT. (and here and here)
Decoding data from an FM subcarrier.
Lots of other good SCA Data stuff. Commercial receivers.
John Tokash 