Greetings,
I have installed EDZ's for 80m and 40m at right angles on my tower at
40' using the formulas supplied by two sources (leg length = 630/f, 450
Ohm ladder line length = 135/f). Attaching an MFJ-249 at the ladder line
(no balun) indicated an SWR of >3:1 on the 80m EDZ and I couldn't even
get the meter off the peg on the 40m version.
I understood from articles by VE3ERP and the ARRL Handbook that with the
proper ladder line length, a 50 Ohm match could occur. A transition to
coax could be made for the run back to the shack with no tuner
necessary.
Dimensions are as follows:
80m (40m)
169' (85' 1") 169' (85' 1")
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1:1 Balun
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Coax
Am I mistaken about not having to use a tuner, or is one always
necessary? Should I be using a 4:1 balun? Any help would be appreciated.
In the mean time I guess I'll go outside and put up my GAP vertical for
low band work.
73,
Tom N2CU
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