[TowerTalk] frequency determined antenna switch

[Tony Brock-Fisher]

There are multiple ways to do this. Many radios (Icom, and maybe others) output an analog voltage that tracks frequency bands. You can decode this with an analog level detector to drive relays. Top Ten makes (made?) relay boxes and decoders for this. 

Another approach is to use a computer logging program. Many of these (N1MM and others) can look at the radio's frequency and output the Top Ten code on the parallel port, which can be used to drive antenna relays. N1MM allows you to map the frequency to the antennas, even having multiple antennas per band which can be selected.

-Tony, K1KP