Hi Frank...
Well, you have a tiger by the tail if you are going to bring the hot end of a
radiating wire near a house where other folks are trying to watch a Muntz tv
with a 21mc IF and listen to k-mart special stereos with 40 foot of zip wire
for the speakers...
It can be done... You will need a decoupling radial - quarter wave of wire for
each band - hooked right to the ground screw on the rig/tuner and either run
out the window, or wound around the room...
Next in desireability is getting the end of the antenna further from the
house, as you suggested... You can try a random length of coax to a balun and
decoupling radials at the feed point... I can imagine several problems with
this... But, if you wish to try this approach you will benefit from an air
core choke at the end of the coax instead of a balun... I recommend a simple
solenoidal coil of the coax itself - 4" diameter.... Cheap, effective, and the
core cannot saturate or exceed the curie temp... Do put out ground radials
from the braid side of the coax - as many as you can!.... Put a tuner at the
rig end of the coax and also do a single 1/4 wave decoupling radial for each
band right at the rig/tuner, as I described above... For this type of
installation I strongly recommend either 50 ohm hardline or 3/4" / 7/8" catv
cable to minimize loss in the coax... This should play.... If you have
problems on 1 or 2 bands with rf feedback in spite of all the precautions add
6 foot to the coax...
Better yet, is an L-Network at the base of the antenna - it won't kill you to
walk out and move the alligator clips to change bands, in fact exercise is
good - with the coax air-coil for a choke and the plethora of ground
radials... Wind your own L match coil out of # 10 / 12 enameled wire, 2 to 3
inch in dia. -and make the capacitor from two aluminum pie tins and use 2
layers of 2 mil plastic from garbage bags as the insulator... Do the air
choke on the coax, and radials under the antenna and at the rig...
Oh, and by the way - have fun!
Denny
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