gm0vhr wrote:
> I can run one of the beverages at about 290 deg that is over 1150' long but
> the feed point will be about 600' from the shack. Is this too long for a
> beverage and is the feed point a little too far away? I know coax losses
> are less important with RX ariels but is there a sensible limit when it
> come to the distance to the feed point?
At P40V in 1988, we had to sets of Beverages out in a huge field. One was
for 80M and the other for 160M. The five 80M Beverages were about 450 feet
long with a center about 1000 feet from the shack. The three Topband
Beverages were 900 feet long with their center about 2000 feet from the
shack. At each center, we had a switch and a preamp run off of an automobile
battery. They worked incredibly well over coral. You may not need a preamp
at 600 feet, but it can be done with the dimensions you mention.
73, Wayne, N7NG
Jackson Hole, Wyoming
The feed point for Our beverages at W3PP were at least 600 feet from the
shack. We used RG-6 75 ohm flooded coax. The longest beverage we had was
around 600 feet.
I am not sure there is a lot to be gained with the extra 500 feet, If you
have the room I think you might consider two 525 footers in different
directions or leave them unterminated so that they are bi-directional. On
the other hand at this qth, 300 feet is the max I can go and 1100 feet would
Seem like paradise to me. We hear GM3POI very loud here with what ever he
Is transmitting with. He is probably listening on beverages to hear us on
the east coast of the USA.
73
Chet N4FX
One, the feedline is not too long. Youll maybe need to treat it for
common mode in a couple of places.
My only BEV is 600' long to the NE (eu). It works well on 160 but it
works better on 80. That tells me that it would be better on 160 if it
was longer. My feedline is about 500' of RG6. I have a 10db preamp at
the head end, with power supplied through the coax.
Have fun
Dean W5PJR
Tijeras, NM
290 deg is an excellent direction from UK for most USA. However a bit
off beam for W7s, KL7s, KH6s etc which come in 330deg/360deg.
1150ft is very long, and will make the beverage very directive (only 51
degrees beamwidth and low angle 22 degrees elevation lobe, -6dBi gain,
approx), a real killer rx ant if the DX is close to that direction.
If I was in happy position of having that antenna, and didnt have space
for other directions, I would try putting a relay in the middle as could
hear a wider azimuth range when half or third the length. A 600ft
beverage 4ft high has approx 73deg beamwidth and 30 degree elevation
main lobe, -10dBi gain. A 400ft beverage has approx 97deg beamwidth and
40 degree elevation main lobe. */Has anyone else tried this with one
wire?/ *
600ft feeder is no problem. Satellite TV duofoil-type coax is
relatively cheap and has relatively low loss on 160/80m.
Beverages 4 ft high are between approx -5dBi to -15dBi gain, so another
few dB even from lossy coax should not be a problem with modern
sensitive rxs, or if necessary with external extra preamp in shack. I
use up to 1200ft without problem. Take normal precautions for common
mode and critter attack!
73's
John G3PQA
Feeding your Beverage 600' from the shack should not be a problem.
Loss in most kinds of coax will be very low at lowband frequencies,
and it will be nothing like the negative gain figures you'll realize
from the Beverage itself.
The feed point of my Beverage is over 1000' from the shack, and I feed
it with RG-6 coax. The preamp is in the shack so that I can easily
disconnect it during storms. Most of the time, signals from the
Beverage are within 1 S-unit of the signal strengths I see on the
Inverted-L on 160.
The coax, of course, is buried in conduit. Couldn't keep the horses,
goats, & donkeys away from it, when I hung it on the fence.
73,
Brad, KV5V
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160 meters is a serious band, it should be treated with respect. - TF4M
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