Last Sunday I sent the e-mail below to Force12, but no reply sofar.
I would like to have the antenna going before IOTA-contest coming
weekend. Anyone who had the same problem (and fixed it) ????
73/DX de Osten / SM5DQC e-mail: sm5dqc@algonet.se
To customers service dept. (That´s probably Tom, N6BT, sorry to
bother you Tom).
First the story:
I bought an EF-240s from Sam, SM3PZG (Leges Import) in early May
and had problems tuning it (assembly was VERY easy), I got the low
1:1 SWR very broad but around 7180 KHz even though I did set it up
for 7030 KHz according to the manual. The antenna is on a heavy steel
carnk-up, tilt-over lattice tower, and have to tilt it up and down when
adjustements are made. Finally with the driver jumpers at 8 inches from
center I got it down to 7005 KHz, but very narrow bandwith SWR.
Unfortenately I had the loading wires streched to much and, YES I did
cut them........ The beam worked fine on 40 CW with FB etc. but did
look awful. Ordered new loading lines wires from SM3PZG and got them
a week ago. Today I had the beam down, changed loading lines and now
the beam looks great BUT again with driver jumpers at 12 inches from the
center I have 1:1 SWR from 7160 to 7175 KHz.
Second, what to do:
What have I done wrong ????? As I have mounted the antenna this time
precisely according to the manual, someone else must have had the same
problem ????? If I adjust the driver jumpers to get down again to the DX-
frequency 7005 KHz, what happens if I still keep the reflector jumpers at
5 inches from center, that is FB etc. ????
Seems my manual is from 1995 (dw240sn3.002), any modifications since
that time ????
Thanks in advance for your answer. I was very pleased with how the antenna
works at 65 feet, worked all DX I could hear, but now after I installed the new
loading wires I will leave the antenna until I get an answer. It might be
simple,
I am a DX´er, not an antenna engineer.......
73/DX de Osten / SM5DQC e-mail: sm5dqc@algonet.se
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