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BARRETT 4050 HF SDR TRANSCEIVER - OPERATING AND INSTALLATION MANUAL
Noise generated by motor or electrical accessories on the vehicle may cause
objectionable interference to the received signal. This noise enters the receiver
either by means of the battery leads or the antenna system. Providing that the
recommendations concerning battery wiring given earlier in this manual are
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noise problems result from pick-up by the antenna. Practical cures involve
either preventing the noise from being generated or minimising it from being
radiated by the wiring connected to the noise source.
Interference Suppression Kit
(Barrett P/N BCA20008) is available to assist in noise suppression and contains
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The techniques involved in noise suppression include re-routing of wiring,
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equipment in good working order as worn brushes, loose connections and the
like, will increase the amount of noise generated.
Before attempting to cure a noise problem, the source (or sources) of noise
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noise in the receiver with motor and accessories on and that with motor and
accessories off.
If a detectable difference does exist, turn off all accessories one by one until
a change in noise results. Continue, noting each contributing unit until there
is no detectable difference from the “all off” noise level. (For accessories such
as alternator, motors, instruments etc. a wire or drive belt may have to be
temporarily removed for this assessment.) After identifying each noise source,
they can be worked on one at a time until an acceptable level of suppression is
achieved.
Another approach to this problem is to remove or disconnect all possible
sources of noise then replace and suppress them in turn.
Some suggestions for suppressing particular noise sources follow:
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