Antenna Questions, novice
JimC wrote:
I'm trying to sort through some material I have read regarding setting
up an antenna for general shortwave reception, probably in the 4,000 -
12,000 MHz range(??), for a modest SW receiver (table top model with AF
gain, RF gain, band spread, S-meter, BFO Pitch adjustment, antenna trim,
etc.). From the materials I have read, I can get reasonably good
general SW reception (though not great reception of code or Ham
broadcasts), with an antenna of around 30 - 100 feet. As understood, the
antenna wire could be simply routed around the room; or, put in the
attic; or, alternatively, strung outside, suitably in an "inverted L"
configuration. (I'm not going to get into directionaly antenna arrays
for Ham reception at the present time.)
If I string a straight length of antenna wire outside (which would
probably be longer than the wavelengths of most signals I'll be
listening to), is its reception directional, and if so, should it
preferably be "aimed" in a certain direction? (Assuming that I would
probably want to listen most often to stations that are located east
northeast of our location here in Texas?) I'm guessing that it should be
perpendicular to the direction from which most signals would come from.
Also, is there a significant advantage to running it at an angle rather
than horizontally, as in some designs?
Thanks for any suggestions.
Jim
As a novice that just put up an antenna for listening maybe the
following will help.
I intially put up a windom antenna in the attic and had much RFI from
inside the house.
I did a lot of reading and asked many questions here and ended up with
the following.
I ended up installing an "inverted L" antenna. It is about 85 feet
long horizontal and 15 - 20 feet high as it covers the backyard. I
installed a hook at the peak of the house roof and a heavy spring off
an aluminum screen door. Attached to this I have about 45 feet of
nylon rope between it and the insulator at the start of the antenna
wire. This gets the wire at least 15 feet away from anypart of the
house to reduce RFI. From here the antenna wire, (#14 gauge insulated
stranded wire from Home Depot) goes 85 feet to an insulator that is
attached to a short lenght of nylon rope attached to a mast on an
outbuilding. The wire then goes down about 15 feet to a 10:1 balun
which is mounted directly to a ground rod sticking about 15" above the
ground. From the balun I buried 135 feet of RG-6 outdoor coax about 5"
under the grass and ends at a ground block at the house. The ground
block is also connected to another ground rod installed nearby. From
the ground block I have 50 feet of RG-6 coax that goes into the house
and terminates at a TV type matching transformer with the guts taken
out so I can attach to my recievers screw terminals.
The interferance that I got with the attic antenna is not there and
this antenna is quiet and I recieve many more stations. I am happy
with this setup and since I used white nylon rope, antenna wire, and
insulators it is not an eye sore.
Hope this helps.
Brian
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