> In the 1980's, Colatchco (W1FC and W1CF/SK) sold, among other things, an
> 80/160 meter vertical which I believe had a relay switch. Perhaps someone
> can bring that info forward since they must have had a viable solution. I
> don't think they used a trap!
Joe et al,
You are mostly correct--Colatchco did have a 80/160 vertical. W1CF, who
lived a few miles from me, did have a prototype that used a relay to switch
in a 160m loading coil about 2/3 the way up the vertical. A wire run inside
the vertical supplied DC power to the relay. A small wire top hat connected
to the vertical just above the loading coil. It was a 60-foot high antenna.
However, I don't believe they ever marketed this version, or if they did,
they only sold a few.
I have some old Colatchco product literature which does describe a 80/160
vertical, 42 feet high, which used an "encapsulated resonator" at the top of
the vertical and acted "as a loading coil on 160 and as a trap on 80". It
did not use any mechanical switching. It also had a small wire top hat
above the resonator. This was the version that I believe they did market
although I'm not sure how many they sold.
73, John W1FV