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[NOTE: An updated version of this article can be found at wb3gck.com.]
I
love rummaging through our local dollar store. One of the
biggest bargains in our local dollar store is speaker wire.
(See Figure 1.) You
can
get 50 feet of two-conductor speaker wire for a buck. Not too
shabby. I always keep a bunch of the stuff on hand for
experimenting with antennas.
Using a single 50-foot roll of dollar store speaker wire, I made a
simple 50-foot random wire antenna with counterpoise wires to cover the
40, 30
and 20 meter bands. I stashed the whole kit in a
zip-lock bag and always keep it on hand as a backup antenna
system
whenever I operate in the field. (See Figure 2.)
With a simple antenna tuner
of some
sort, this will get you on the air in a pinch, should your primary
antenna fail.
Here's all you have to do:
- Separate the
conductors so that you now have two separate
50-foot wires.
- For the radiator, take
one of the 50-foot wires and crimp a
small ring lug to one end (right over the insulation). (See
Figure 3.) This gives
you some place to tie a line to in order to hoist it up. On
the
other end, just strip off a half inch or so of the insulation.
You can leave it bare or add whatever kind of connector you
want; whatever works best with your tuner.
- For the counterpoise
wires, take the remaining 50-foot wire
and cut it so that you have a 33-foot wire and a 17-foot wire.
If
you only want to work 40 and 20 meters, you can stop right here.
You now have counterpoise wires for both of these bands.
- To provide a
counterpoise wire for 30 meters, take the
33-foot wire from Step #3 and cut it so that you now have a 23-foot
wire and a 10-foot wire. Strip off about 1/2-inch of
insulation
from one end of the 23-foot wire. Install a quick disconnect
connector of some sort on the other end, so that you can join the
23-foot and 10-foot wire sections together. The idea here is
that, with the two wires connected, you have a 33-foot counterpoise
wire for 40 meters. With the two sections separated, you now
have
a 23-foot counterpoise wire for 30 meters.
In operation, just hoist one end of the 50-foot radiator up in a tree
or other suitable support. Connect the other end to the hot
side
of your tuner. Connect the 33-foot and 17-foot counterpoise
wires
to the ground connection on your tuner and lay them out on the ground.
(See Figure 5.) When you want to work 30 meters, just
disconnect the
quick-disconnect on the longer counterpoise wire. Pretty
simple, eh?
Any type of
simple L-tuner should work fine for this.
Please note that I wouldn't recommend using this wire for a permanent
outdoor antenna. It's really not suited for that kind of use.
But for temporary outdoor use, it'll do just fine.
Besides,
if the wire goes bad, you can always replace the whole thing for a
dollar! |
Figure
1. Dollar Store speaker wire
Figure
2. Complete antenna in a ziplock bag
Figure 3.
Ring lug
Figure 4.
Quick disconnect
Figure
5. Diagram
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