Duffy & Dave, et al,
I Too have noticed your findings in experimentation with VHF/UHF beams.
1. Yes gain does seem to favor the high end . When I adjust for max gain,
I'd really like to have Max gain antennas for every 2 MHz section of the
band but that just isn't practical.
2. Yes SWR does climb more rapidly going down in the band. As the
frequency approaches the resonant length of the Reflector everything goes
haywire.
One simple method of compromise on HF Yagis is to set the directors and
driven element for the phone band, and the reflector for the CW band, and
use a tuner when you need to. The effects are much less noticeable in the
Phone portion where you're more likely to need an amp, and you still have a
beam on the CW portion.
This was successfully used when the 2m repeater band was opened up from 2
MHz years ago.
73 de Jim Bradshaw, ac6tk@cybertime.net
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