Alternator Whine And Other Distracting Noises; Technical Notes - Firecom 3000A Installation & Operator's Manual

3000A
TECHNICAL DA TECHNICAL TECHNICAL
TECHNICAL TECHNICAL
AL AL ALTERNA AL AL TERNA TERNA TERNAT T T T T OR WHINE TERNA OR WHINE OR WHINE OR WHINE OR WHINE
AND OTHER DISTRACTING NOISES AND OTHER DISTRACTING NOISES AND OTHER DISTRACTING NOISES AND OTHER DISTRACTING NOISES AND OTHER DISTRACTING NOISES
Because of the level of ambient noise present with the
apparatus motor running, alternator whine and other
noises may not be noticed in the communications sys-
tems until an intercom is added. A noisy system will al-
ways be apparent, however, once an intercom is installed.
Alternator whine and other noises on the communica-
tions circuit are due to two main causes:
→ → → → → Improper installation.
→ → → → → A faulty alternator.
Generally, the problem is not caused by the alternator. It
is usually the result of a difference in signal potential be-
tween the apparatus radio signal ground and the inter-
com signal ground. Additional sources may also exist in
the apparatus electrical system
T T T T T o reduce or eliminate alternator whine, perform o reduce or eliminate alternator whine, perform o reduce or eliminate alternator whine, perform
o reduce or eliminate alternator whine, perform o reduce or eliminate alternator whine, perform
the following: the following: the following:
the following: the following:
Connect the apparatus radio to the cleanest power
source possible; a source without motors (e.g., heat-
ers, windshield wipers, etc.), sirens, strobes, or flash-
ers.
Use the same precautions when connecting the in-
tercom power.
Ensure that all radio power and ground connections
are clean and tight.
Ensure that the radio power and ground wires are of
sufficient gauge to prevent a signal developing
across them.
Keep all battery connections clean and free from
dirt and corrosion.
Use noise filters on radio and intercom power if
needed.
TECHNICAL TECHNICAL TECHNICAL ASSIST TECHNICAL TECHNICAL ASSIST ASSIST ASSISTANCE ASSIST ANCE ANCE
Our technical staff is just a phone call away. Contact us
at 1-800/527-0555.
cont. cont.
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