[TowerTalk] NVIS Antennas

[Tom Rauch]

> Given that we have for decades communicated with subs
using
> miles of buried antennas, and folks like G3BDQ and others
have
> experimented with buried Ham antennas, one is well-advised
to
> avoid absolute declarations about what does and does not
work
> always and forever ... at least you won't hear that from
this
> "expertise-challenged" corner!

No one ever said contacts can't be made with crappy lossy
antennas. At least I didn't say it.

All I said is the only thing that happens electrically as an
antenna is lowered below 1/8 to 1/4 wl  (depending on earth)
is losses go up dramatically.

That been measured in field strength studies of NVIS
radiators in Thailand, as well as confirmed in my own
systems.

The idea HF groundwave with horizontal polarization extends
for 20 miles with enough level to cause fading is pretty
silly. More than likely what they had going on, if they
actually measured anything at all, is feedline radiation
allowing a significant vertical component. Vertically
polarized signals can follow the earth at HF, although 20
miles might be a real stretch.

Once a bad idea gets started it's tough to stop.

73 Tom