[TowerTalk] N6BT, Force12inc and JK Antennas/Tennadyne Log periodics

[Paul Veal M.Ed N0AH]

When speaking of 5 bands, I have used the Tennadyne T-8 log periodic for 
years using it on a 20 foot Glen Martin tower on the roof-

The T8 is an amazing antenna. Always a bit awkward to speak about one's 
station, but for discussion sake, using ClubLog stat's, running the TS-590S 
and 100 watts, our station had the highest number of 10M contacts in CONUS 
in 2013. Running 100 watts into the T8- Also in 2013, our station placed 
very high in 12 meters, and decent showings in 15/17/20 meters.  Everyone 
complains about the high SWR's with these antennas, but they work 
exceptionally well. The T-8 is on an 18 foot boom. I had been using trapped 
tribanders but gave up on them with wet trap issues, etc......also, the wet 
skin effect on a log periodic goes unnoticed- This always drove me upside 
downs using the trapped tribanders-


Bryon "Paul" Veal M.Ed
Assistant Director - ARRL Rocky Mountain Division
STEM School and Academy AB0BX Amateur Radio Club Trustee
U.S. Amateur Radio Call Sign- N0AH
n0ah at arrl.net or bryonveal at msn.com
text 303.703.8448
-----Original Message----- 
From: Jim Brown
Sent: Friday, November 21, 2014 10:37 AM
To: towertalk at contesting.com
Subject: Re: [TowerTalk] N6BT, Force12inc and JK Antennas

On Thu,11/20/2014 12:38 PM, Kelly Taylor wrote:
> f every manufacturer applied the same level of, shall we call it 
> optimism?,
> to their claimed gain and F/B figures, it appears the C3 worked better 
> than
> fixed-spacing, three-el tribanders.
>
> Be curious to know if that's held up in actual on-air operation.

The first link is to a report by Ward Silver, N0AX, on measurements that
he and K7LXC did almost fifteen years ago on the C3 and several other
tri-banders. Ward is now editor of the ARRL Handbook and ARRL Antenna
Book. Both of N6BT's antennas measured better than the tribanders in
their size and class. That is, the C3 beat the small tribanders, the
larger one beat the large tribanders. In those days, the others all used
traps.

http://www.championradio.com/HF-TRIBANDER-PERFORMANCE-TEST-METHODS-RESULTS.2

The second link is to a collection of applications notes by N6BT on the
topic of antenna design. In it, he went through the math to show that
the gain numbers claimed by manufacturers of tribanders were 3-5 dB
greater than a theoretically ideal antenna. In other words, they were
lying. There's plenty of other stuff, including dimensions for his
designs of monoband and multiband Yagis for the HF and VHF bands.

http://www.championradio.com/ARRAY-OF-LIGHT-Straight-talk-about-antennas-and-related-subjects-Third-Edition.113

My neighbor, W6GJB, owns two C3SS tribanders that we use on Field Day
and California QSO Party county expeditions. They play very well.

73, Jim K9YC
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