Ocean Technology Systems PowerCom Surface Station 3000S, Руководство пользователя

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ZONES OF SILENCE
Large natural or man-made objects can block acoustical transmission under cer -
tain conditions, in much the same way that a rock blocks a fast-moving current
of water. Close to the backside of the rock, in this example, the current is absent
and the water seems still. A short distance away, the current is flowing again.
Similarly, acoustic energy in the water can be blocked if the transmitting source is
close to a large object. On the backside of the blocking object, a “zone of silence”
is formed in which reception of the transmitted signal is not possible. Divers can
reduce “zones of silence” by moving away from, around, or above the blocking
object until communication is re-established.
Under some conditions, when a diver’s suit and body are directly between the
transmitting PowerCom Surface Station (3000S & 5000S) and the diver’s radio,
a small zone of silence may be created that prevents reception. This effect can
become greater at longer ranges. The diver turning 45 degrees in any direction
eliminates this zone of silence.
For more information on Wireless Communications, visit the Learning Center on
our website at: WWW.OTSCOMM.COM