Full wave antennae on 137kHz?
On 7/20/2017 2:14 PM, 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?
There is a lot yet to be fully understood about access to the LF bands
in the US. But if you are under a HV line, they might well be using the
line for carrying control signals for the power grid. The technology,
PLC, doesn't play nicely with ham usage.
How do you find whether a power line is using PLC? For some reason you
can't find anywhere a list of places that are OK, or that are not OK.
Instead you have go to a website and ask, and wait to be told yes or no.
So we (the hams) are in second place when it comes to sending
information over these lines.
(There is a fairly new line at something like 250KV close to my back
yard. I don't yet know whether it is carrying PLC.)
Bob Wilson, WA9D