Lectrosonics UCR411a - Manual (Page 15)

UHF Digital Hybrid Wireless™ Receiver
Rio Rancho, NM 15
The receiver is supplied with two straight BNC whip
antennas. In some circumstances remote antennas
may be useful for improving reception. Position remote
antennas at least three or four feet apart and at least
three or four feet from large metal surfaces. If this is not
possible, try to position the antennas so that they are as
far away from the metal surface as is practical. It is also
good to position the receiver so that there is a direct
“line of sight” between the transmitter and the receiver
antenna. In situations where the operating range is less
than about 100 feet, the antenna positioning is much
less critical.
Note: Be careful about the length of cabling from
antenna to receiver. Long cable runs can have
serious signal loss. Lectrosonics has in-line RF
amplifiers suitable for compensating for long cable
runs. Contact your dealer or the factory for more
information.
A wireless transmitter sends a radio signal out in all
directions. This signal will often bounce off nearby walls,
ceilings, etc. and a strong reflection can arrive at the re-
ceiver antenna along with the direct signal. If the direct
and reflected signals are out of phase with each other a
cancellation may occur. The result would be a “drop-
out.” A dropout sounds like either audible noise (hiss),
or in severe cases, may result in a complete loss of the
carrier and the sound when the transmitter is positioned
in certain locations.
Antenna Use and Placement
A UHF dropout sounds like a very brief “sshhht” or
a “swishing” sound. Moving the transmitter even a
few inches will change the sound of the dropout, or
eliminate it. A dropout situation may be either better or
worse as a crowd fills or leaves the room, or when the
transmitter or receiver is operated in a different location.
The receiver offers a sophisticated diversity design
which overcomes dropout problems in almost any situ-
ation. In the event, however, that you do encounter
a dropout problem, first try moving one of the remote
antennas at least 3 or 4 feet from its original location (or
move the receiver if the antennas are attached directly
to it). This may alleviate the dropout problem at that
location. If dropouts are still a problem, try moving the
antennas to an entirely different location in the room or
moving them closer to the transmitter location.
Lectrosonics transmitters radiate power very efficiently,
and the receivers are very sensitive. This reduces
dropouts to an insignificant level. If, however, you do
encounter dropouts frequently, call the factory or consult
your dealer. There is probably a simple solution.