Hi everyone,
I have made a short vertical (for portable use) out of
some insulated masting. I want to use this with a
capacitance hat and base coil. The vertical section
will begin about 10 feet above ground (bolted to the
back of my van) and will extend 28 to possibly 38 feet
above that (depending on wind etc). I will have at
least 8 ground wires from this 10 foot feed point
sloping down to the ground in a circle around the
antenna (Each about 50 feet long; more if possible).
My questions are:
1. I understand that the capacitance hat wires can
slope down if necessary. I was planning to use 4
capacitance hat wires. They will probably slope down
at a 45 degree angle (I'll try to get them more
horizontal). How close to ground can these wires come?
Is it better to make them shorter and have the ends
higher up?
2. I have also read here that the base coil can be
used for loading + impedance matching. Is there any
easy way of knowing how large to make this coil to
start with? I don't own an antenna analyzer or
anything like that. I assume that I tap the center
coax conductor to where I get maximum RX noise, but
how do I do the impedance matching part? I have bare
#12 copper wire for the coil. Can anybody give a good
estimate on how large I should make this coil to start
with? Is is possible to get a near 1:1 match using
this system or do I still need a tuner?
Thanks in advance for your help.
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