Thanks Dennis.
Those SWR readings are very useful. I just wonder how to go about
adjusting the driven element if it's needed. I have zero experience
with this. Would I first adjust the innermost section for 10M, then
the middle for 15M and then the outermost for 20M? And I suppose it's
best to try and get resonance on each band near what's shown in the
manual for your chosen band segment, which the other elements were
already set for, correct?
I haven't decided yet on which balun I'll use but I'll definitely
consider what you said about the BN-4000.
A lot of people recommended using a more modern antenna., but I don't
have a lot of options on what antenna to put or how to put it up.
Space is very limited here. You can get an idea of how limited from
the photo on my QRZ page. When I put up my tower a year ago, I was
also shopping around for a good antenna, but it had to be practical
for the space I have to work with. I found a lot of antennas with no
reviews and/or questionable specs, and the better, well known antennas
were all too large. I was familiar with the TH6 but couldn't find one
at the time. The size of a TH6 is just below the limits of what I can
have up on the tower, but there's not even enough room to fully
assemble one on the ground while keeping it completely on my own
property. Even if there was, it would be very difficult/expensive to
maneuver for getting it up the tower. Building and raising 2 12-foot
sections is doable though. My contractor uses a very large bucket
truck that can hold each section lying flat on top of the bucket. With
a strong support like that plus 2 guys in the bucket, it shouldn't be
too hard to put up one section, then bring up the 2nd one and guide it
into the boom to mast clamp. If anyone knows of a better, modern
tribander of comparable size that can be put up in a similar way, I'd
like to know what it is.
73, Gerry KA2MGE
Gerry, I want to add two things to the discussion. I bought a used
TH6DX in 1977 and used it for 5 years before replacing with a 10-15-20
meter stack of Yagi's. It is an OK antenna to start with. It is great
on 10 as it is four full size elements, mediocre on 15, and ok on 20.
I used the "low phone settings" and with 100+ feet of coax the SWR on
20 at the low end was about 1.8. The SWR on 15 meters was about 1.4
and I could never get it down regardless of fiddling with the driven
element. 10 meter SWR was very good on CW and the lower part of the
phone band. Do NOT use theBN-4000 balun. While it is good
electrically, the entire balun is potted with a very hard substance.
After several years of being exposed to heating and cooling, the balun
began cracking. Finally, the teflon coax inside pulled away from the
coax connector leaving an open circuit. It is no fun to climb a tower
to replace the balun. Regarding putting up the TH6 in halves, I
considered that. However, the TH6 is a heavy antenna and it would be
very difficult to assemble the antenna this way while you are at the
top of the tower unless you have a helper up there. What I did was
assemble the boom and individual elements on the ground and put each
element on the boom while I was at the top of my tower. As others have
said, there are better designs out there now. I replaced the TH6 with
a 204BA, and two Wilson 4 el beams. These ran circles around the TH6.
To its credit, the TH6 is very rugged. After I left Minnesota, I put
it back up at my new QTH in South Dakota before installing the
Christmas tree arrays. The TH6 then went on a new higher 80 foot tower
when I moved to Ohio and served until 2012 when it was replaced by a
Tele HyGain TH-11DX. The reason for not putting up the individual
yagis is that they were destroyed in a tornado while in SD. The
TH-11DX has provided outstanding service on five bands. 73 Dennis W0JX
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