I have used an HF5B for about 10 years at 35' and here is my experience
with it. I sent a version of this to Gene, but after reading commentaries
on the antenna, thought a different slant might be useful. How good or
not good the antenna is depends on the standard of comparison, even the
type of vertical that might be used as an alternative.
1. Set-up: SWR figures in spec sheets are good if one takes an
afternoon to set it up. I pointed mine at the sky and made all the
adjustments per the book. Hit a snag, so started that band over again and
hit the spot. Have never had to change any adjustment on the matching
rods and capacitors, even thought the beam, dissassembled into two
complete elements and the boom, experienced a cross-town move 7 years ago.
I have heard of many users getting less-than-spec performance who were
hasty with the set-up. My own (2) installations have had less than 2:1
SWR across all spec'ed bands. I use a bead-type W2DU 1:1 balun at the
feedpoint.
2. Mechanical: It has withstood winds exceeding 50 mph without any
problems. The light design appears to slip the wind well. I check it
yearly and renew the "It's Not Butter" but other than that, everything
mechanical appears in good shape.
3. Performance: just about as advertised: a good 2-element Yagi on 10
and 15 meters with about 2 S-units F-B. On 20, some directionality, but
not much gain, if any. A reverse direction beam on 12 (due to natural
resonance of each element at about 25 MHz), and a dipole on 17. Assuming
a height of about 35', the elevation angles on 15-10 meters favor the
HF5B's gain, but 17 and 20 may be toss-ups against a vertical on the roof.
My uses have been for casual QSOs and net-type operations where having a
lower F-B was useful in hearing participants off the rear. Any success in
pile-ups, however, will be the result of operator skill, and not the
antenna.
I am thinking of upgrading the system to a Tennadyne T-6, but may put that
off until next year do to backlog of projects. For a relatively
lightweight small scale set up for 20-10, the Tennadynes appear to
be interesting alternatives to the HF5B, since they weigh less
than 10 lbs more and will have more uniform performance over the
bands. However, they have a much larger turning radius. I have no harsh
words at all for the HF5B, since it has done all the Butternut specs said
it would and held up for a decade--and might go another. It certainly
will not compete with a 3-element Yagi or better, and perhaps not even
with an optimized monoband 2-element Yagi. But the keys to getting
everything out of it that it can do are 1. patience in set-up, and 2.
getting it up at least 1/2 wl on 20.
Hope these notes are useful.
-73-
LB, W4RNL
L. B. Cebik, W4RNL /\ /\ * / / / (Off)(423) 974-7215
1434 High Mesa Drive / \/ \/\ ----/\--- (Hm) (423) 938-6335
Knoxville, Tennessee /\ \ \ \ / / || / (FAX)(423) 974-3509
37938-4443 USA / \ \ \ \ || cebik@utk.edu
URL: http://funnelweb.utcc.utk.edu/~cebik/radio.html
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