A transponder, such as the Trig Avionics TT21, that has the operating panel
separate from the transmitter/receiver box, will allow the
transmitter/receiver to be installed behind the pilot and thus
considerably reduce the required cable length (and hence losses) to a
tail-fin antenna.

At 03:10 20 February 2009, Gary Emerson wrote:
Andy wrote:

This is interesting as it will probably require some large coax to keep
the antenna loss to less than 1.5 db which is what was recommended in
the microair transponder install manual I have. The RG-58 is limited to

10 ft of coax length and that sure isn't going to get you to the fin
from the instrument panel...