Interesting research worth a read and watch.
I think the devices used are around the $185 mark.
type RX band- TX band- Function Application
width width
UT-100A 6-8 MHz 2-8 MHz Rx-Tx General
UT-100B 2-4 MHz 2-8 MHz Rx-Tx amateur
UT-100C - 2-8 MHz Tx General
UT-100D 2-4 MHz - Rx amateur
http://www.idealez.com/hides/home/en_US/
http://www.ebay.com/sch/hides168/m.html?item=322470042239&hash=item4b14b65a7f%3Ag%3AGc4AAMXQVT9TBXWO&rt=nc&_trksid=p2047675.l2562