[HCDX] Antenna Attenuation
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[HCDX] Antenna Attenuation



Hi Everyone;

For the past 18 years I have had a 1500 foot terminated Eastern beverage
running at about 75 degrees, from the Northern Oregon coast. It runs on
top of an old barbed wire fence. My idea was to add 1 foot plastic PVC
pipes to connect the wire to, as I did not think it would work too well
right on top of the fence. What I did was to attach the PVC pipe to the
metal fence post and then tape the #12 insulated wire to the PVC pipe. I
use standard plastic electrical tape. This was back in 1984.  I replaced
the wire last year with new, but after I attached the new wire to the
PVC pipe I began to notice the directivity wasn't as good. It look
several months in checking to discover that. Not a big amount, but still
enough you would notice it, especially as picky as I am.  A couple weeks
ago I was checking over the antenna and I changed a few places where the
wire was connected to the PVC pipe and moved the wire through the pipe.
I noticed the antenna was more directional during the day.  I wonderd
could the RF being picked up was somehow shunted to ground affecting the
directivity. The antenna used to be more directional, but I added more
tape in recent years after the high winds on the coast tore the antenna
up. We have had much worse high winds the past 4 or 5 years with ones
100-120 MPH. That does not help antennas. Fortunately the beverage is
only 5 feet off the ground that protects it somewhat.  Remember this
wire is #12 insulated house wiring, taped to a plastic PVC pipe 12
inches above the fence, so I fiqured it is insulated well enough, but I
was wrong. I decided to buy some 4 inch wire ties and pull the wire out
from under the tape and tape the tie to the PVC pipe and then run the
wire through the tie, so  the wire is on the outside now. 
One thing I noticed right off is the increased directivity and a bit
more gain at the bottom of the band. KFXD-580-Nampa ID (5 KW), is much
better at 400 miles East now daytime. It will be interesting to see how
it does at night.  I never thought I would get attenuation from
insulated wire & a PVC pipe. 

73s,

Patrick Martin
Seaside Oregon

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