I simulated the fence wire with MMANA.
On HF (80m, 40m) I got the expected (bi)directivity and low offset angle.
But on 500kHz the horizontal pattern is almost omnidirectional and
the offset angle is 78 degrees.
It seems that (at least in theory) even 1200 foot is too short to be
long on 500kHz ...
Or does MMANA not work properly ?
73, Rik ON7YD
At 15:52 21/01/2008, you wrote:
Hello LFers & Lowfers,
I've been testing a 1200 foot end fed longwire mounted on
an existing fence-line and coupled to the receiver with a
3:1 turns ratio isolation transformer. The antenna is 3
feet off the ground, with the far end left un-terminated.
The "ground" for the cold end of the antenna winding is
a stainless steel screwnail driven into the trunk of a
cedar tree at ground level.
The antenna is aligned 50/230 degrees true, which from my
QTH favours Europe/UK off the front and the mid-west U.S.
off the back. Listening to ATC frequencies from Gander
and Shanwick in the 2500 to 3000 kHz. range, the longwire
is several S units stronger and MUCH quieter than my 80 M
On 500 kHz. I've been able to copy the XGR transmissions
with better signal strength than off my PA0RDT mini-whip
or untuned delta loop. The same holds true for listening
around the broadcast LW & MW bands or NDB chasing.
The greatest advantage is that signals are well above the
noise on the longwire.
Thinking outside the box can sometimes yield a surprising
result, if that's the only option you've got!
73, J.B., VE3EAR - VE3WZL
Solar and wind powered
Lowfer " EAR" 188.830