If your scanner receives strong interference or electrical noise, move
the scanner or its antenna away from the source.
If you are operating the scanner in a fringe area or need to improve
reception, use an optional antenna designed for multi-band coverage.
(You can purchase this type of antenna at a local electronics store.)
If the plug at the end of the cable does not match the antenna jack,
you may need to purchase an adapter.
Trunking
A few state Highway Patrol agencies, and many local and county
public safety services, utilize a new type of transmission scheme
known as trunking. Trunking allows a number of agencies (such as
city police, fire, highway and sewer departments), and/or a number of
divisions within an agency (police patrol, detectives, radar teams,
warrant servers...), to operate on a single radio system without
interference from one another. The agencies may share a three to
twenty or more channel radio system in which particular divisions hop
about the assigned frequencies as they become available.
A dispatcher may be communicating with a precinct’s patrol units on
856.7125 one moment, and then receive a reply from a patrol car 30
seconds later on 858.4875. In the meantime, 856.7125 will have been
used by two sewer workers. It all happens transparently to the radio
users. To them they’re the only people using the system and they
never have to change channels. To the scanner user, however, it
becomes a challenge to follow a conversation. All a scanner user can
do is either wait for the radio to resume scanning to the next frequency
or use
H
to move off of an uninteresting conversation.
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