There have been many postings here about Beverages and EWEs as we contesters
try to improve our low-band receiving capabilities. I recently learned of
some experimentation being done here in north Texas by N5FY and KE5OW on an
antenna they call a "Beverage on the Ground" or BOG. They've also
experimented with a "Beverage Under the Ground", or BUG, which is buried
under an inch or two of soil to enable mowing.
Paul, N5FY, posted some information about BOGs and BUGs on the local packet
cluster. The attractive feature of a BOG from a contesting perspective is
that you might be able to unfurl one of these babies across your neighbor's
lawn on "certain" weekends of the year! Paul is not on Internet, but he is
interested in gathering additional information on this subject for a magazine
article. If you've done similar experimentation, Paul would be interested in
your findings. Please respond directly to me, not to the reflector. I'll
summarize, post the summary here, and pass your comments on to Paul. Thanks!
- Phil, N6ZZ -- N6ZZ@aol.com
>From Paul, N5FY:
Here is some info on my 160 meter receiving antenna setup.
I've been using eight (8) BOGs at about a 45 degree spacing,
starting with, of all things, North. Each is #17 insulated wire about
220 feet long, lying on the ground. Each is terminated in a 180 ohm
resistor and is fed with coax. The incidental signal current induced
on each coax is isolated from the BOG by small 'current' baluns.
One wire of the signal side of each balun is connected to earth
ground via a 3 foot long copper clad or brass welding rod (about
1/8 inch dia.). The shield of the coax is connected only to the
balun, not directly to ground at the field end. In the shack the
shields of all coaxes are grounded. The terminating resistor is
connected to earth at the far end of the wire via another welding
rod. Just like a regular Beverage antenna, the loaded end, the one
with the resistor, points towards the direction you want to favor.
By the way, don't share a ground rod between wires. In fact it seems
best to space the rods apart so that no two wires share the same ground
space. Probably 6ft spacing is sufficient to insure that no couping
can take place between systems.
Dan Hearn, N5AR, has put down a 140 ft version for 80 meters and
reports similar good results.
Let me tell you: "These things really work". Unlike the so-called
EWE antennas that only provide a null in vhe undesired direction,
the BOG actually has a pattern similar to a 1.5 wave length
Beverage antenna. When lying on the ground over short cut grass
they don't seem to be affected by rain so long as they aren't
submerged under the water. I noticed no affect from the couple of
inches of snow that we got this year. Although Dan heard some
"snow noise" on his 80 meter version until the charge in the flakes
dissipated. Maybe I didn't get up early enough that morning.
In addition to the BOG, I've done some experimentation with a
Beverage Under Ground, or BUG. It consists of a wire that's
buried just under the surface of the ground, which would enable
permanent installation, mowing the yard, etc.
So far, the BUG hasn't worked out well. Although it works
quite satisfactorily in completely dry weather, its already weak
signal output goes in the dumpster with a little rain. Even though
not a lot of experimentation has been expended toward finding the
optimal length for the BUG wire, it does seem that the dielectric
loading effect of the earth surrounding the wire does require it to
be even shorter for the same directivity pattern. This could be an
additional advantage to those with space restrictions. While the
BOG wires seem to operate best on this soil at length of about 220ft
for 160 meters. I got similar results on 160 with a length of
150ft on the BUG in this soil which has excellent conductivity.
-Paul, N5FY
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