A Top Band 1/4 wave vertical?
gareth wrote:
This current interest (and privacy furore) about drones set me thinking,
what an interesting way to elevate a TopBand vertical, but being a temporary
structure, not breaching any planning permission (Brit) or zonal (Yank)
restrictions.
One problem would be the flight time / battery life, so one approach
could be to power the drone through the antenna cable (much as with
mast-head preamps), in which case, being tethered, it would no longer be
a drone!
The power considerations, however, would call for too heavy a cable to be
lifted
aloft, so, taking the cure from the electricity grids, perhaps the solution
would be to power with 1kV AC (say, 10kHz, to reduce the sizes of
aloft transformers) going up a twin feeder, with the top band excitation
driving both of the AC feeder wires in parallel?
(Not too dissimilar in principle from the electicity grid using Pilot Tone
protection)
Gareth G4SDW
PS. By varying the frequency and / or phase of the 1kV AC, the
positioning of the ex-drone woulc be controlled thatway.
Ever heard of a helikite?
--
Jim Pennino
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