Following this thread with interest for 2 reasons:
1) I have recently used a couple of different tuners in several
configurations with "long dipoles" (several combinations of open wire,
outside baluns, etc and had some fun with 160M.) I finally ended up
using the Radioworks full size Carolina Windom 160 and the MB-V-A
tuner - works great with power on 160 and has been dynamite on the other
bands, of course!
2) Now my question: I recently completed my first tower/yagi project,
ending up with a Force 12 tribander. The SWR is below 1.5:1 everywhere
I'm interested in, if not the whole band of interest. However, I
elected to run the feedline through the MB-V-A to make it "perfect" for
my amp. During this past weekend's WAE RTTY contest, after a couple
hours of running about 900W, I noticed significant heat when I put my
hand on the tuner case. It wouldn't peel paint or burn your hand, but
it was quite warm. I had never noticed this when using the tuner with
power to the windom, although I don't think I was ever specifically
looking for it. Both antennas have good "tuner-less" SWR - The main
thing that is different is the feedline length - over 600 ft for the
yagi, mostly LMR-600DB. Is this the source of the heat (?loss) in the
tuner? Gotta get a wattmeter out there! Should I bypass the tuner
altogether if within the amp's specs? Tnx!
WA9ALS - John jfleming@shelbynet.net
http://www.qsl.net/wa9als
----- Original Message -----
From: Ward Silver <hwardsil@WOLFENET.com>
To: Towertalk Reflector <towertalk@contesting.com>
Sent: Tuesday, November 16, 1999 6:04 PM
Subject: [TowerTalk] Tuner Loss - Do Not Panic
>
>
> > > I have a friend who peeled the paint on one of the Dentron tuners
a few
> > > years ago,
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