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Old May 17th 15, 12:53 PM posted to rec.radio.amateur.antenna
Helmut Wabnig[_2_] Helmut Wabnig[_2_] is offline
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First recorded activity by RadioBanter: Sep 2007
Posts: 135
Default Antenna tuner question

hello,
I am a newcomer in amateur radio shortwave and so far
have built a dipole antenna with ladder line.

Not a G5RV, not a ZEPP, not a DOUBLE ZEPP, not a DOUBLETT,
but a dipole, a non-resonant antenna, if you know what I mean.

Unfortunately the antenna feedpoint is 25 meters away.
Now I am searching for a remote automatic tuner
for balanced feed line, aka hen's ladder, and coax input.

Presently I am using a BG-430 military Generalstab radio tuner.
http://www.radiomuseum.org/r/zellweg...em_se_430.html
It is the lower right foto, the thing in the center with the 4 black
feet. Works only 80 and 40 meters.
In more detail:
http://www.radiomuseum.org/r/zellweg...geraet_ag.html
Look at the schematic, upper part.
The input coax connects to the "balun" transformer,
and two variometer coils connect to the antenna output.

I have not been able to find anything useable on the market.
SGC tuners are ruled out, they are strictly for long wires
and nothing else. They make their money with the UN and other
mobile militaries, amateurs are not existent for them.
Amateurs use dipoles and ladder lines.
No, you can't use an SGC on a dipole.
If you do, you are wasting your money.

What rermains are MFJ and LDG coax tuners in combination
with a 1:4 balanced transformer. Thus the 25 m coax line would see
a fine SWR and no losses due to reflections. The coax from the tuner
output to the balun input make very short to avoid reflection losses.
Very high voltages will oscillate there!

What I like less is the balun at the high end, would prefer
a symmetric tuner with a balun at the coax input and balanced
symmetric output, like the Zellweger tuner does.
The MFJ-974HB is also a fine thing.
Really symmetrical at the tuning circuits, but manual.

100 Watt are fine, 400 Watt are better. (Maximum in Austria)
Can you help me, please?
OE8UWW