I recently bought a TH6-DXX in excellent condition and I'm getting
ready to put it up at 70'. With the space limitations I have, this
antenna is well suited for me since it can be put up 1/2 at a time - 2
12-foot boom sections instead of the complete 24' boom. Once it's up,
it would be very difficult to make any changes. I plan to use a
Hy-Gain BN-4000B choke but also have a Radio Works Y1-5K or could make
one from RG-213.
I operate CW mostly and that is where performance is most important to
me. Phone coverage is important too, though not as much. Looking at
the SWR plots in the manual for the band segment choices (CW, Lo Phone
and Hi phone) it seems that CW would be the obvious choice for me.
Those curves are steep though, and I wonder if with CW, I would still
have full coverage of 15 and 20 meters, using a tuner and possibly
reduced power for the high ends of those bands. Same goes for 10
meters, say up to 29.2 MHz but a lower freq. could be acceptable
there.
The other choice would be the Lo Phone setting, and using a tuner /
possibly reduced power at the low and high ends of the bands,
including where I spend most of my time on CW.
I couldn't find much info on this topic when searching the TT archives
but did find the old post below, and I'm a little concerned to say the
least! Was the antenna actually designed to be used only in one
segment of each band, even with a tuner? Will I be Ok with the CW
setting or would that give me serious problems on phone? If I used the
Lo Phone setting, would I have problems in the CW portions of the
bands running 750W and a tuner?
I used a TH6 frequently many years ago at a club station, but I don't
know how that one was set. It seemed to work fine on any freq but I
probably never tried it above 29 MHz on 10 meters. I would have been
using a tuner when the SWR was high, but there never seemed to be any
loss in performance - which was always very good. Never had to reduce
power from 800W either. The choke there was just several turns of
RG-213 as described in the manual.
Any advice is appreciated.
Thanks,
Gerry KA2MGE
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You can see the bad news: choose from CW, low phone, or high phone.
Hope you don't need more than one of those segments :-( Also, you
can't "cheat" the SWR curves by using a tuner. The pattern will
significantly degrade at the frequencies where the SWR is high. This
is why, IMHO, given a choice between a TH6 and TH7, picking the TH7 is
a no brainer. I used to have a TH6. I would never go back to that.
Rick N6RK aschnabolk wrote: >_ Look at Page 2 of 7 in the "TH6DXX"
(last one listed) Curves are there. As_ >_ I_ >_ remember mine when it
was up, curves were similar._ >_ 73_ >_ Al W2OIB_
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