Gosh I think I just beat a hornet's nest with my 10 lb balun... HI HI.
I did not go into a lot of details because this topic is a bit "off
topic" for this forum.
I did not give a lot of thought to balun selection when I grabbed that
4:1 balun and installed it. I will give the 1:1 version of the DX
Engineering balun that I have on hand a try today.
I have tried a CM choke with 10 or so large fair rite beads slipped over
a 24 inch long piece of RG-213. The beads are about 1.25" long and 1" in
dia (or so). Please do not bug me about the core numbers, I do not know
as the duct tape has pealed off the labels. Anyways with that CM choke
at the feed point of the 4:1 balun, it did not help either. From the
sounds of things, that was my mistake right there. I should have
connected the CM directly to the ladder line. My bad.
K4TAX is correct about the MFJ 929 tuner not having a balanced output.
I only use the 34ft doublet on 20M and above - but it does "tune-up" on
30M. I have a very nice pair of qtr wave verticals for 80 & 40 meters.
Regarding the 12 ft coax cable the measured VF is .66. I used a spectrum
analyzer and tracking generator to measure the VF of the coax off this
reel of cable.
I am well aware of the potential folly of using something close to a 1/4
wavelength and did so deliberately to get the antenna to play "nicer" by
deliberately jacking up the Z the tuner would see. My dirty sleazy trick
worked. Sounds like something an EMC engineer would do - oh yea - I am
one! HI HI
As far as for which band I was on when the MFJ 929 locked up, I believe
it was 15M. The week before last I was attempting to quickly slap
something together to play in the CWO contest that ran Friday and Saturday.
I would like to be able to place the tuner at, or very near the feed
point of the balun.
It would be interesting to see what a real network analyzer has to say
about that mess of an antenna I was trying to use. But then my director
of engineering would not be to pleased with me dragging home a $50,000
network analyzer. I guess I will settle for what my MFJ 259 (non A, B,
or C) says.
Guys, once again thanks for the input, I will install the 1:1 balun and
report back in this afternoon.
VY 73, Don KO7i
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