开云体育

I'll attach the measurements of my 450-foot long doublet, yes 2 by 225-foot
wires, which has a schematic of the setup at the end. The ladder line is
nominally 400-ohm. There is a section across the back of the garage which
consists of about 45-feet of AWG #6 bare wire strung an inch apart on
electric fence standoffs. Outside, there is roughly 20-feet of 450-ohm
window line to the feed point and inside the radio room (my wife calls it
my 'box) about 5 feet of window line. That connects to the CMC and into
the L-network matching network that consists of a shunt variable 30 ?H
inductor and a series variable capacitor of 80 to 1000 pF @ 4.5 kV whose
output is adjusted to 50 ± j0 ohms. The output at 50 ± j0 impedance (from
the variable capacitor) then feeds about 5-feet of RG-8 to the output of
the AL-82. The input of the AL-82 then feeds an Alpha Delta 2-way switch
with another coaxial jumper of about 3-feet to go between the Icom 7300 or
the 7610. All coax is RG-8.

All this started when we moved into this home about 6.5 years ago from
losing everything in the forest fire in 2012. The appliances in the old
mountain house had pre-Chinese switchers in them - FCC tested. The new
appliances in the new home all contain multiple Chinese SMPSs with no
attention paid to EMC and associated CM noise coupled onto about everything
that conducts. We recently had to replace a (only!!) 6-year old
refrigerator (Samsung) with a 'made in the USA' unit (Hotpoint). I had to
build and install a 'rather' aggressive CMC on its linecord to alleviate
the noise from its SMPSs (From China, with Love). It's been an uphill
battle to keep all that noise out of the antennas and feedlines. When I
finally (now who is dense) discovered the usefulness of the lowly CMC in
accomplishing that task, I went to town. I believe I am finally winning.
However, all radio astronomy antennas are located a fair distance from the
house out of necessity.

Dave - W?LEV

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*Dave - W?LEV*
*Just Let Darwin Work*