I had quite a few inquiries about Dog Loop and other antennas.
Let me briefly describe some of those that I used, they might be helpfull to
those with limited space, noisy locations or add some diversity.
"Dog Loop"
This came about as I needed something in the hurry to listen on 160. I had
laid Radio Fence for our Springer Spaniel "Whiskey" earlier, but our dog got
smart and did not need the "fence". So I had this rectangular loop, burried
in the ground about 1" deep, dimensions of 32 x 56 meters. I figured I should
try it for reception on low bands. About 1/3 from the corner (close to shack)
on 56m side I inserted Beverage transformer 600:50 ohm. Transformer is wound
on ferrite core with 7 turns and from the ground end - 3 turns of small coax
with center conductor soldered to the shield (electrostatic shield). RG58
then runs into the shack. This antenna seems to be dead at first, but you
definitely need a preamp about 20 - 30 dB. I use Ameco with fixed gain. Not
sure if there are any directional properties of this antenna, but it seems to
pull in signals from around that Inv. Vee at 30' up in the tree can't, nor
when I had balloon vertical. It also discriminates against local TV garbage
radiation and power line noise, dimmers, etc. It seems to work also on 40 m,
but with less sensitivity.
"Coiled up, folded wire"
This came about by accident once in CQ 160m contest. Back in Toronto (46x120
ft city lot) I would stretch my Beverages in the park, just for the night. If
hudlums didn't rip them off, they would stay up whole night. In the morning I
would wind the antennas up on the drum. So Saturday night I am "just
checking" the band about 5 p.m. and I hear this G3 (was that SZA?), but this
was on my coiled up NE beverage, which looked like this: I had ant tuning
unit in the shack in the basement. Wire went out through the window to the
back wooden fence about 30" high for about 20' (going abt N), made right turn
on the top of the fence for abt 25' (going E), then another right turn on the
top of the fence for about 50' (going S), then the wire dropped to the
ground, went back underneeth the last leg (going N) for about 35' and there
was the rest of the wire wound on spool, sitting on the ground. (Inductively
loaded fractal?)
So when I heard G booming in on the coiled up beverage, I figured boy what an
opening will we have. I ran out, disregarded daylight and hudlums and
stretched the wire in NE direction for about 600 ft about 9 ft above ground.
Figured will get jump on KV4FZ! Run inside the shack, and... G is gone, no
trace of him. Maybe QSB? Nope! Not a peep! Could it be screwy antenna? Run
outside, coild the beverage back, and voila... G is back. I sat back
scratching my head. Antenna handbooks did not explain this, antenna software
wasn't around yet, "experts" did not "discover" it yet. Since then, if I have
piece of wire laying around I throw it out, match it and see what happens.
When I visited W1BB, Stu had at his home QTH some wires running around the
fences also, and said that sometimes he would hear stuff on them that other
antennas could not.
"Street Beverage"
Even piece of wire laying on the ground can work miracles sometimes. Back in
Toronto I needed Beverage going East. The only way to do that was to use the
municipal facilities in the form of road. I would lay the Beverage in the
corner of the stone gutter on the asphalt road, "fastening" it with handfull
of mud here and there. Wasn't terminated, needed E-W directions. It was also
"night" beverage, I would coil it up for the day. Sure brought in those
skewed Eu openings and W6s.
"AC outlet antenna"
I am not telling you to do this. (Not responsibel for any screwups liberals
can make.) I just describe what I did.
When K7GCO wrote about using AC outlet for a receiving antenna, I though guy
is nuts! But having great respect for his work, I figured I have to try it. I
got old AC plug (one that you could flip is better), took the biggest HV
capacitors I could find in my junk box, about 1000 pF, soldered to one pin of
the plug. Connected wire to other end of capacitor, insulated with layers of
heat shrink tubing and hooked to my antenna tuner. I was expecting avalanche
of power frying F$%#@ line noise. No such thing!!! It was quiet and I could
hear stations on the thing!!! Needed preamp, signals were down, but it sure
worked better than wires in the sky on receive. Looks like house wiring up to
about my nearest pole transformer was acting as antenna. (Fractal AC wiring?)
It worked so well that I did not get around trying another Ken's recipe -
trying to flush the wire down the toilet. But this one could work especially
well for expeditions staying in high-rise hotels!!!
Beverage drum.
I found it convenient and speedy to use my beverage coiling drum. It was made
of old coax spool/drum about 14" diameter, made square frame for it with
handle and a crank. I would lean the drum against something, grab the end of
wire and walk unwinding the wire. The other end would be tied around the drum
and signal the end of wire by sudden stop. I could pretend I was jogging. I
could put about 20 beverages on that drum. It is good to put little name tags
on the wires so next time you know which one you are pulling.
To bring the beverages home to papa, just untie the end and start cranking,
winding the wire back on the drum. I kept visiting scrap yards and scaning
for drums with wire. I bought about 10000 feet of 5 conductor flat
(splittable) copper cable for $10 (canadian - 1980)
On transmit I used mostly Inverted Vee and half slopers, tied accross the
street to unsuspected neighbors house, other end to the swings in the park. I
would extend my 65 ft tilt over TV tower with all the booms I could scrounge
to get that apex as high as I could. Those were the golden days of top band.
With junk like that, I could manage few world records. Nowadays you have to
travel to geographically advantaged location. I am not complaining, at least
I get to see more of the world and make new friends.
Soo, look around and see what you can do under the circumstances. I hope that
we will hear you - hearing more in the next one! No excusse not to hear me
in the next contest now that I let some secrets out! Hi
Have fun and CU on 160!
Yuri Blanarovich
K3BU, VE3BMV, P40A etc
one of "TESLA Contest Sparks" N2EE, NT1E
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