>From experience the military uses HF NVIS for voice and low data rate
transmissions for beyond line-of-sight communications and for what's called
the "Life Line". They are basically very inductive half-loop antennas
mounted on the edge of a roof around 36" above the roofs of command
vehicles, HMMWV's etc. Mounted inside the vehicle is a high speed antenna
tuner that switches banks of capacitors in and out. I've used this antenna
in the Amateur Band on 40M and received good signal reports out to Virginia
from northern NJ. Don't expect to run out to AES or HRO etc for this
antenna. It goes for $10K a copy and personally it's not worth it based on
the tuners performance. We are looking at SGC's whip and tuner system
hoping that will perform the same or better at less cost.
'73,
John
N2HMM
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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