Micron 700 Series, Руководство пользователя

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Interference
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24
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tx700ins2master.doc
(Noise in this case means a twittering type of sound 'birdies' from the interfering signal). With the Companding
system, interfering signals are held down in quiet passages but rely on the masking effect during loud passages.
Under severe interference or under weak signal conditions, sudden large audio input level changes can produce a
short period of increased background noise. In this situation the wanted signal strength should be increased to
prevent this happening.
MULTICHANNEL OPERATION
If two radio microphones are used simultaneously at the same location, their operating frequencies should be
chosen with care. Multichannel sets of frequencies have been calculated by Audio Engineering for operation in most
frequency bands. The use of these sets is recommended and should be chosen (in whole or in part) whenever
possible. When any two mobile radio transmitters operate close together, unwanted intermodulation signals will be
produced due to interaction between the transmitters. The closer the transmitters are together and the closer they
are in frequency, the stronger the intermodulation signals will be. If the intermodulation signals fall within the band
of a third channel, interference effects can occur when the received signal from the third transmitter is weak. Similar
intermodulation effects can occur in the input stage of a receiver if the unwanted signals are very strong. There are
many situations where frequencies, which are incompatible, have to be used. The following precautions may help to
minimize the problems. Separate all the receivers (or the antennas). Try to avoid producing strong unwanted
signals in each receiving antenna. Site the receivers (or the antennas) to favour their own channels. As far as
possible, keep all transmitters at least 0.5 metres (20ins) apart.
Typical Transmitter Intermodulation Products