Wayne, for some reason, I erroneously thought you were a General class ham
license holder. Since you are a tech, pretty much everything I wrote in my
previous message is not applicable to your current situation.
In your present situation, a light weight, 30 or 35 foot tower would be very
doable with a dual-band, 2 m and 70 cm, beam, if that is the way you want to
go. I even had an 11 element dual-band beam up on a push-up pole and turned
it with a TV type rotor, and it worked just fine. Again, I've had all kinds
of VHF/UHF antennas too, and for the money and ease of putting them up and
not having to be concerned about them, I, personally, prefer a vertical.
However, the beam has the advantage of being very directional, especially
one with several directing elements. You can hit repeaters over quite a long
distance with modest power. The vertical does not require any special tower
or rotor and transmits and receives in and from all directions at the same
time, thus, omnidirectional. There are several excellent choices of both
types. The key to evaluating such antennas is their gain, the higher the
gain, the better the antenna. In the case of a beam, you are looking at
forward gain; you want high forward gain and a high front to back ratio.
This gives you maximum radiated power in the desired direction off the front
of the beam, but also gives you maximum rejection of any unwanted signals
that might be coming in from the back of the beam. The 11 element beam I had
gave me pin-point signal radiation off the front of the antenna, but when I
swung my beam around, away from a repeater or unwanted signal, I could
barely hear it, if I could hear it at all; thus, giving me excellent forward
gain, but also excellent front to back ratio. The truth is that it was too
sharp, and I had to have it pointed right at some repeaters; otherwise, I
didn't hear them because even the side rejection was quite high.
The area in which you live and what you want to do with your gear play a
major role in deciding what you need.
Ron, K8HSY
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