A total of six frequencies would be needed to maintain 24-hour 90
percent reliable communication for a distance of 100 miles over an
Assuming a 30-foot high antenna and 75-foot high trees, any
vegetation (trees, bushes, grass, etc.) below or immediately in front
of the transmitting antenna will absorb radio energy causing a weaker
received signal by the distant station(s).
The best transmitting
site is a wet plowed field. The wet soil reflects the radio energy
instead of having it enter the earth and being absorbed.
emphasis is placed by commanders on having all vehicles well into the
A compromise must be made if satisfactory communication
is to be maintained. A camouflaged HF set in a clearing with proper
separation from trees that match the take-off angle/distance
requirement is a must. Remember not enough coax is issued with the
HF set to allow the vehicle to be in tree line and keep the antenna
separated from the trees.