The Boxx TX antennas are 25 Pounds each, around $42,50 US. FOB London You need a broadband antenna that can handle 5.1 to 5.9 GHZ, The 5.7/5.8 antennas do not work very well when you use the lower channel. Laird makes a good one,RD-2458-5-RTNC,but not nearly as rugged as the OEM ones, but less expensive.
The OEM antennas are available from Boxx Communications in LA or me at Dynamic Video Electronics, Mississauga, On., Canada, petedve@rogers.com, I also stock the Laird antennas.
Peter Crevier
Dynamic Video Electronics
905 569 1137