sdaniel:

Main coupling to the chain link fence with be by capacitive coupling
(inductive coupling, I suspect, would be negligible.

The chain link fence will have a "natural resonant frequency" of its own,
and favor some freq or range of freqs, and those freqs harmonics. This
could have a beneficial and/or counter effect on antenna depending on band
operation. This antennas impedance would be difficult to guess and/or
determine, one might try running the antenna though various ratio baluns
(or a multi-tapped rf transformer) to see if signal can be improved.

Any electrical interference the fence runs close to will increase noise
level. At my location there is a chain link fence which encircles tens of
acres... it boosts my LW TREMENDOUSLY! I have a weird "gamma match"
arrangement I have experimented with and tap the chain link fence with. I
have not experienced "noise" of any type but imagine it can occur under
circumstances favorable to its generation, and under proper conditions
which encourage it...

For the ~9 mhz range, just running an alligator clip to the fence, though
a 9:1 balun seems to work well for me... if you like toying with such
things, can be fun.

Hook it up and experiment, there is someway you can use what exists to
your advantage! Probably get ideas off the web, if you and I and more
have thought about this, probably many more have played with it...

John

On Sun, 14 Aug 2005 07:56:46 -0700, sdaniel13 wrote:

It's been hot as heck in NYC for the last couple of days. Yesterday, to
escape the heat, I spent much of the afternoon in Prospect Park,
where's there's usually a nice breeze and cooler temperatures. On a
whim I brought along 100 ft of wire and my HF-150. I laid the wire out
in a 'snake' configuration, right on the ground, and was pretty
impressed with the results. I was in a quiet spot there in the Park.
Even so, when people describe this as a low noise antenna, they aren't
kidding. Using a couple of tree limbs, I raised the wire up about 7-8
ft. The increase in noise was noticeable, and the s/n ratio was a
little worse.

I realize that the classic snake antenna uses coax, not wire. However,
ordinary old insulated wire sure seemed to work well for me yesterday.

I've read around on the web about these antennas and their low noise
characteristics, but I'd be interested to hear about any experiments
the readers of this group have done. I'm especially curious about how
the presence of metal objects in the immediate vicinity of a snake
antenna would affect its performance. For example, suppose you took
200ft of insulated wire and 'stiched' it through the bottow row of
'links' on a very long chain link fence. I can't imagine a stealthier
antenna than this, but would the fence muck things up?

Steve