Re: [TenTec] The problem with directly end fed wires

[Joe Giacobello <k2xx@swva.net>]

Stuart, you're right:  you need a tuner; you get RF in the shack with 
certain antenna lengths; and a good ground is essential.  However, 
although I usually prefer to ignore isolated anecdotal reports, I really 
have to say I have had remarkably good experiences with end fed random 
wires for portable operations on many occasions over the years.  In many 
cases the antennas were relatively short, low and obstructed and the 
grounds were what was easily achievable under the prevailing 
conditions.  Frankly, I have frequently been surprised at how well they 
have worked.

I use an IC-706 for portable operation and an MFJ-16010 toroidal L-match 
for the tuner.  I have about 300 ft of about 19 gauge wire (obtained 
from a WWII Gibson Girl emergency kit) on a deep sea fishing reel.  I 
usually wind up getting one end of the wire as high as possible and I 
use as much as possible.  The other end of the wire is merely brought 
into my room through some convenient opening, usually a window.  More 
often than not, I use a cold water pipe for a ground.  Typically, I work 
40 though 10 meters.  I have used these makeshift stations in VK, HS, F, 
I and the US with more than just satisfactory results.  Usually, the 
stations I work refuse to believe that I'm just using a random wire.

When I was an apartment dweller, I sneaked up end fed wires, usually not 
very high, and used them for years with acceptable results without being 
detected by the "authorities."  Admittedly, I never had one 400 feet 
long, but the shorter ones that I use for portable operation radiate 
more or less like dipoles.  Resistance losses can enter the picture when 
the radiator length gets very long.  Last year I unsuccessfully tried to 
use a 3/8 wavelength end fed wire on 160M, but the RF in the shack 
became a real problem at greater than 800W output even with short ground 
leads, counterpoises and other remedial measures.  My 170 foot center 
fed Zepp was much more satisfactory on this band despite its short length.

73, joe




Stuart Rohre wrote:

> Besides needing a tuner to handle the very high impedance of the longer end
> fed wire; as it does get to multiples of 1/2 waves, you have more and more
> of the response coming from ONLY the direction of the far end of the wire.
> If you want an omnidirectional antenna, this is NOT it.
>
> The poorest antenna from number of contacts it generated was my 400 foot
> long wire pointed in the wrong direction, and besides it had lots of RF in
> the shack problems!
> -Stuart
> K5KVH
>
>
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