Hello Topbanders,
It is getting cold in the Northeast and as I get older, I dislike the cold
even more.
In April of this year, I replaced my Cush craft D40 40 meter rotable dipole
with an OptiBeam OB-4030 dipole for 30 and 40 meters right at the top of the
mast. The overall length of the antenna is about ten feet longer and I am
assuming that it has added some additional capacitance to my 100 foot shunt
fed tower with a Cush craft X7, A3WS, 5 EL M2 6 meter yagi and the new
OptiBeam dipole.
My match on the tower went from 1.0 x 1. To 1.9 x 1 after I installed the
new antenna. In terms of loss, this isn't a huge change but my amplifier
doesn't like the change. Before I spend a lot of time running back and
forth to the tower making random changes, any thoughts as to what I can do
to improve the match. I'm currently using one series capacitor 1000PF for
the matching network. I have attempted to adjust this capacitor but it
looks like the 1.9 x 1 is the low point. Perhaps some thoughts - increase
or decrease the spacing of the shunt wire? Move the connection up or down
on the tower?
Before I get to crazy, just wanted to look to the base of knowledge on this
reflector for your input.
73 and tnx in advance.
Bob K3UL
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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