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UNDERSTANDING BANKS
Channel Storage Banks
To make it easier to identify and select the channels you
want to listen to, channels are divided into 10 banks of
30 channels each. Use each channel-storage bank to
group frequencies, such as the police department, fire
department, ambulance services, or aircraft (see “Guide
to the Action Bands” on Page 52). For example, the po-
lice department might use four frequencies, one for each
side of town. You could program the police frequencies
starting with Channel 1 (the first channel in bank 1) and
program the fire department frequencies starting with
Channel 31 (the first channel in bank 2).
Service Banks
The scanner is preprogrammed with the frequencies al-
located by police, fire/emergency, aircraft, marine, and
weather services. This is handy for quickly finding active
frequencies instead of searching through an entire band
(see “Scanning Service Banks” on Page 23).
UNDERSTANDING TRUNKING
In the past, groups that broadcast frequently, such as po-
lice departments, were restricted to transmitting on just a
few frequencies. This resulted in heavy traffic and often
required 2-way radio users to wait for a specific frequen-
cy to clear before transmitting.
Trunked systems allow more groups of 2-way radio users
to use fewer frequencies. Instead of selecting a specific
frequency to transmit on, a trunked system chooses one
of several frequencies when the 2-way radio user presses
PTT (push to talk). The system automatically transmits
the call on that frequency, and also sends a code that
identifies that 2-way radio user’s transmission on a data
channel.
This scanner lets you select the data channel frequency
that you want it to monitor, so you can hear both the call
and response transmissions for that 2-way radio user
and therefore follow the conversation. (You cannot listen
to the data channel itself).
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