Hi Gord!
Sorry for the delay, I just returned from a week in Australia and
operating the phone Sweepstakes at KH7R!
A Yagi structure doesn't have a "resonant frequency," but, of course, the
design of the driven element results in a resonant frequency at the feed
point. My 10M Yagi was modelled at 28.0, 28.4 and 28.9, and the driven
element is designed to have excellent VSWR across this entire frequency
range.
I prefer the T-match because -- in my experience -- its extremely bullet
proof; however, the beta match is also an excellent choice provided you
use a very high quality balun that uses a teflon insulated coax (assuming
KW power levels are intended). The balun is the weak link in a split
driven feed, don't be tempted to cut corners here!
73
Frank
W3LPL
donovanf@sgate.com
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