After much procrastination I installed a BOG (beverage on ground)
antenna in the farmer's field behind the house. With the recent snows
and bunches of snow mobile tracks it looked like the only solution.
After reading ON4UN's comments and rewinding a core to give me a good
match at 230 ohms I 'deployed' the antenna. Walked about 600 feet of
wire ( no attempt was made to figure an optimum length) on the ground
and grounded it with a 3 foot rod and termination of 230 Ohms. Feed is
with RG6 and other than the matching at the feed point and a LARGE wad
of RG6 to attempt to choke off stray signals it's installed 'as is'. The
antenna feed point is about 200 feet from the transmit antenna. SWR is 2
to 1 at the shack end of the RG8 which connects to the RG6. The RG8 runs
under ground into the shack for about 100 feet.
Preliminary results confirm ON4UN's comments. The BOG is way down in
output but useable without a preamp but the ICE preamp and about 10-15
DB works well to bring up to the level of the EWEs in the yard. The BOG
appears to be about 15 db down from the EWE antennas. The front to back
has not been verified yet but it appears to be quiet and have pattern. I
worked GM4BES tonight and Graham was very Q5 on the BOG but noisy on the
EWE (the EWE is close to the transmit antenna and this maybe proves that
I need to put a relay in line or the BOG is inherently quieter than the
EWE Use of a preamp to match the output of the Bog to the EWE shows a
definite increase in noise compared to the BOG)
If anyone has experience in the BOG antenna area I'd be glad to hear
from them. If this really works out well I should be able to deploy this
type of antenna every year and do the decoupling correctly as per W8JI
specifications.
provided for your information and perusal
Dan W8CAR
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