HI Rik...
I use a 2000' and 1000' unterminated longwires that simply lay on the ground
and are used specifically for 500khz and down. I have been very impressed
with their performance on NDB's etc. Beacons ranging in the 5000-7000 km
range are heard on a nightly basis. Just wondering what your software say's
for these as far as expected performance.
Vern - VE1VDM
-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of Rik Strobbe
Sent: Tuesday, January 22, 2008 9:58
To: [email protected]
Subject: Re: LF: Fenceline longwire
J.B. ,
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 inverted V.
>
>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
>EN93dr
>
>http://www.hurontel.on.ca/~weazle
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