Full wave antennae on 137kHz?
On Thu, 20 Jul 2017, Gareth's Downstairs Computer wrote:
Drove onto the field on Tuesday and was dismayed to
see a big banner marked Tomlinson, which portended
a bum job, but it turned out to be a scorcher being
a fence judge at the Dauntsey horse trials.
Taking my cue from the coupling loop that feeds a
mag loop antenna, and sitting pretty much under
the 400kV pylon line, I wondered about the possibility
of using a loop to couple into the electricity grid and
so giving the equivalent of a Beverage at 137kHz?
COnsidering that in the US the LF bands aren't yet available because they
need to deal with the power company using low frequencies over the power
line, you might end up causing interference.
But also, there was all that power line communication in the past
(university radio stations, intercomes, remote speakers and I forget what
else) but it stayed mostly on the power line. You needed to be relatively
close to the AC wiring to get the signal. Though maybe long distance
power lines are different.
Aren't you more likely to have success using a fence around a farm?
Though you need the right location, and maybe the right neighbors.
But what did they do in the old days? Everyone was down below the current
AM broadcast band in the early days, which is why hams were banished to
the "useless" shortwave frequencies. Did they have full length antennas
back then, or make do? They did try for long antennas but surely many
couldn't fit a full length antenna. But I'm sure lots of magazines from
the early days would turn up useful things, if you've got the space.