[TowerTalk] Feeding a multi band loop (cloud burner) with balanced line

James Apple wb1dog@hotmail.com
Mon, 17 May 1999 17:00:51 PDT

I just upgraded my 80 meter full wave horizontal loop to use balanced line 
(450 ohm) for the first 50 feet then coax (bury-flex) for the last 20.  At 
the transition I'm using a w2du 1:1 balun.  I expected this to be a upgrade 
for the system, less loss etc,  but my tuners now only find a match only on 
15 meters.  When the antenna was feed with all coax I could get a good match 
on all bands.  Even on 15 I seem to only get to about 3:1.  I have tried 
both a LDG tuner and the internal tuner in a TS-570, they both just give up 
right away.  I put a Autek RF-1 on it and it just reads "H" which I think is 
 > 20:1.  With coax I never saw > 10:1.

I'm suspicious of the balun, I went with a 1:1 because I figured at some 
freq's the impedance would already be very low.  But now I'm wondering if 
anyone else have tried this configuration or is a 4:1 balun the answer.  Or 
maybe the balun is bad,  if while the RF-1 is connected I ground one side of 
the balun, the swr drops ? I don't know why I even tried this test, but I've 
tried about everything.

Any help would be great, over all with a ICE balanced arrestor, ladder line, 
loc, knife switch and balun this was about 200 dollar "upgrade".

Thanks in Advance

Jim Apple (WB1DOG)

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