Hi Gang,
Need some opinions, I currently have a 30' crank-up tower with a 15' mast.
At 40' is a F-12 C4SXL and at 35' is a Cushcraft A3WS w/30M kit
perpendicular to the F-12. I currently have the tower configured with two
shunt feeds. One is on one side of the tower and is for 80/75 Meters and
consists of a drop wire (rg-58) from the 17' level and spaced 36" away. I
use a series cap to tune it across the band. The other shunt wire is on the
other side of the tower and it is also a piece of rg-58 attached at the top
of the tower (at 30') and spaced 48" away. Both shunt wires pull out from
the base 4 and 5 feet to raise feedpoint impedance for matching. The 160m
side uses a Omega match with a 120pf fully meshed series cap and a 3/4
meshed 220pf cap to ground. If you took a "turkey baster" and stood it
upright (so point is up) the shunt wires would follow down the side then out
and around the base. I use a common feedline which connects to the 80 and
160 caps thru a F-12 choke balun. Im on a small city lot and have a
house/patio on the north side and a pool on the west side of tower. Theres
a small 20x30' patch of grass going south and west so radials are few (4 50'
around yard and about 10-15 30' in the grass). Last year was my first on 160
and worked 34 countries using between 100 and 600 watts (above 600 watts cap
flashover).
My questions are........
Would I do better by adding 4 30-50' long top loading wires from the top of
the tower and sloping them down to the fence lines in the corners of the
property?
Would the top loading wires have a drastic effect on the tuing and
performance of the beams above it?
Would there be a noticable difference in efficiency or performance as
opposed to the beams doing the top loading?
Any comments or suggestions would be appreciated.
Thanks Chuck KR6C
kr6c@juno.com
constant@qnet.com (for attachments)
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