On 2/10/2016 6:56 AM, Patrick Greenlee wrote:
Now regarding Beverage antennas... Please excuse my ignorance (The
cowboy philosopher Will Rogers said, "We are all ignorant, just about
different things") but could someone please give me a little detail on
Beverage antennas being poor performers in areas of higher soil
conductivity? I have the real estate (160 acre 1/2 mile by 1/2 mile
black Angus ranch) and have looked forward to experimenting with
Patrick NJ5G
On my own land, I think the FCC map has it right. Verticals work
great, and beverages barely play.
Rick N6RK
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Well, you have me beat; I only have 20 acres, 1/4 mile by 1/8 mile.
When I first acquired the property, one of the first things I did was
to put up a 1/4 mile long beverage (about 1300 feet). It ran
east and west, conforming to the property, which conveniently
allowed me to test it on 2.5 MHz using WWV in CO and WWVH in HI.
I got the wire installed, but had not put in the termination resistors.
I was anxious to listen to it, so I tried it unterminated by
carrying a radio and gel cell the the back of the property. To
my surprise, it heard WWV well, and was deaf to WWVH. I then moved
the radio to the east end, and the result was that it heard WWVH
well, and was deaf to WWV. The beverage was self terminated!
Like a 2 meter dummy load consisting of 100's of feet of small coax. I
eventually did an experiment where I put a relay at the 400 foot
point of the beverage and A/B'ed a 400 ft length vs 1300 feet.
The extra 900 feet was doing nothing other than acting as a
~500 ohm termination resistor. There was no change in received audio
as the relay was switched. I confirmed this by exciting the beverage
with a signal generator and measuring the current along the length.
Sure enough, the current was significantly attenuated after 400 feet.
The result is that beverages are too short to work well on 160 meters.
They start to play on 80 meters. On 40 meters, they are "magic"
listening to long path to Europe in the morning, because they are
"long" on that band.
Rick N6RK
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