Carter, you are indeed lucky.
The funny situation you mention is the same that happened to me when using a
T-Box with external balun.
The SWR did not look that bad at all but the Omni VI+ kept blowing, all the
time and I had to reset the circuit breaker on the 961 power supply.
I understand why I had that problem. It's strange that you had it with a
real symmetrical matchbox.
You are indeed one of the lucky ones.
I'm not making this stuff up.
I'm sure you read "The Doctor is In" in QST, by Joel Hallas, W1ZR.
Joel also did a great review of "new generation symmetrical matchboxes" 7
years ago.
He compared them to the Johnson.
Here's what he wrote about the Johnson:
"While not exactly a part of this review, Matchbox data reported by Witt in
his earlier article is presented for comparison. As noted in the tables,
the [Johnson] Matchbox tuners work well, but **over a typically smaller
impedance range** than their modern counterparts. They also do not have band
switch positions for any of the newer bands, although there is enough tuning
range so they can typically cover 17 and 12, but not 30 or 60 meters. Within
these limits, however, they can still be put to good use. Until the units
discussed in this review became available, the Matchboxes were the only
commercial tuner in wide use specifically designed to work with balanced
antenna systems."
>>> Source: QST, September 2004: "A New Generation of Balanced Antenna
Tuners" by Joel Hallas, W1ZR. <<<
The only thing wrong with Joel's conclusion is that he was apparently only
aware of the US market.
There were other symmetrical solutions available at that time here in
Europe, but if one doesn't speak German or Dutch etc., it's hard to know
about this. Let's see, there was Annecke, Ham Wire, UK Amps, SAMS
(Switzerland), Christian Koppler, and a product made in Holland (can't
recall the name). Those are the ones I know of and I don't know everything.
I'm sure there are more. You see the market spans borders and through lists
like this Ten-Tec list, you can learn about these things.
By the way, LB Cebik wrote the same thing about the Viking and showed how
Annecke improved it. Contact me directly if you would like more info on
this. You can add these changes to your existing Viking.
Cheers!
Rick, DJ0IP
-----Original Message-----
Hmmm...I must be one of the lucky ones. I have a 130-140 foot long
dipole, 25 feet off the ground, fed with ladder (window) line. I am
using a stock Johnson KW Matchbox.
I can get a perfect match on all bands (including WARC bands) with the
following two exceptions:
30 meters: I can only get the match down to ~ 2.4:1 -- but close enough
that I don't worry about it.
40 meters: Even though I get a perfect 1:1 match, I can only run about
500 watts; any more power than that exceeds the 15 kV breakdown of the
ladder line and sets it on fire (don't ask me how I know). <grin>
Maybe if you try changing the length of your feed line to the tuner...???
Obligatory Ten Tec content: Omni 6 (opt 3) and Centurion
Carter K8VT
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