m II wrote in message news:_0Rqd.20232$VL6.6397@clgrps13...
Rob Mills wrote:
I've always had good luck with the Slinky. I've used them indoors in both
vertical and horizontal configurations. Looks to me as a helical wire
(slinky) stretched over, lets say 20 ft would have a whole lot more capture
area than a 20 ft wire.
Ok, it could be the equivalent of a longer wire, but I doubt it. The
induced forces in the slinky would tend to cancel each other out when
the coil is going in opposite direction.
Say the signal is coming in from the side. It will induce a current in
the first half face of the slinky. When the signal hits the far side
face of the slinky, about three inches away, the wire is basically
going in the direction opposite to the first side. This would tend to
cancel out the current in the first half.
I'm just guessing here, but I would think only the (in this case)
horizontal component, not the vertical, of the slinky would add
anything significant to the usable radio signal.
Some proper measurements would be in order here, as what I just said
may be all hot air, but I'm suspecting not.
I would also think that if you have enough room to stretch out a
horizontal support rope/string for the middle of a slinky, you'd have
enough room for a cheaper and most likely as good, wire antenna.
mike
Wherever you end up putting the slinky antenna, make sure it's in a
quiet place. If you walk around your house with a portable radio,
you'll probably find a few spots with a lot of interference, many
spots with considerable interference, and a few spots with only a
little interference. It's in one of these latter spots that you want
to hang your antenna. You might think I'm exaggerating, but just try
it. When you're operating indoors, you're literally operating in the
middle of a noise 'envelope' and it's important to minimize its
effects.
Steve
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