[TenTec] The Next Flagship

[Rick - DJ0IP / NJ0IP]

Jim,

I agree with all of that, but you leave one point out.  "Openwire."
As you well know, the impedance of an openwire dipole varies from band to
band and can be all over the map, up to a couple thousand Ohms.

If you check the specs on any high power remote tuner, only one that I know
of (ridiculously expensive) can tuner anything higher than 1200 Ohms.  Most
stop at 800 or even 600.  THAT is why I said the manual tuners are better.
Of course it depends on which manual tuner.

I was thinking in terms of matching range, not efficiency.

Yes, the Elecraft tuners are tops.
However Kenwood did have one good tuner in its TS-850.  Was nearly as good
as the Elecrafts.
All others I know, before and after are as you described.

73 - Rick, DJ0IP
(Nr. Frankfurt am Main)

-----Original Message-----
From: TenTec [mailto:tentec-bounces at contesting.com] On Behalf Of Jim Brown
Sent: Friday, May 23, 2014 12:51 AM
To: tentec at contesting.com
Subject: Re: [TenTec] The Next Flagship


> Built in ATUs are OK but remote auto-tuners work better.

I question this statement, because it seems to be built on the assumption
that excess loss in the mis-matched transmission line matters a lot more
than it often does. I suspect that most hams using remote auto-tuners have a
poor quantitative understanding of that loss, and may also be fooling
themselves into believing that their antenna "works better" if they see a
1:1 SWR. I also suspect that many (most?) hams using remote auto tuners to
tune wildly non-resonant antennas would be better off either by making those
antennas closer to resonance, or by using a bigger coax between the antenna
and the shack, or both. To get that quantitative understanding, study the
family of graphs showing excess loss due to SWR in the Transmission Lines
chapter of the ARRL Handbook.

Another point -- how well a built-in ATU works depends a lot on its design.
The TT rigs I've owned have not had them; the tuners in the Icom, Kenwood,
and Yaesu rigs have been mediocre, but the tuners in the Elecraft K2 (their
first), K3, and KX3, as well as their KAT500, are all quite good. Again, I
believe that's because Wayne Burdick has always been a backpacker, so he
understands what a tuner needs to be.

73, Jim K9YC
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