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What is Scanning?
Unlike standard AM or FM radio stations, most two-way
communications do not transmit continuously. Your AE230H
scans programmed channels until it finds an active
frequency, then stops on that frequency and remains on that
channel as long as the transmission continues. When the
transmission ends, the scanning cycle resumes until the
scanner receives another transmission.
What is Searching?
The AE230H can search each band and up to 10 frequency
bands
together to find active frequencies. This is different
from scanning because you are searching for frequencies
that have not been programmed into the scanner. When you
select frequency bands to search, the scanner searches for
any active frequency within the lower and upper limits you
specify. When the scanner finds an active frequency, it
stops on that frequency as long as the transmission lasts. If
you think the frequency is interesting, you can program it
into the scanner’s memory. If not, you can continue to
search.
What is CTCSS/DCS?
Your scanner can monitor systems using a
C
ontinuous
T
one
C
oded
S
quelch
S
ystem (CTCSS) and
D
igital
C
oded
S
quelch (DCS) system, which allow squelch to open only
when the tone you have programmed with a specific
frequency is received along with a transmission.
CTCSS and DCS are subaudible tone signaling systems
sometimes referred to as PL or DPL (Motorola’s
trademarked terms for Private Line and Digital Private Line
respectively). CTCSS and DCS are used only for FM
signals and are usually associated with both amateur and
commercial two-way frequencies. These systems make use
of a special subaudible tone that accompanies a transmitted
signal.
CTCSS and DCS are used for many purposes. In many
cases, CTCSS and DCS are used to restrict access to a
commercial repeater, so that only those units, which
transmit the correct tone along with their signal can “talk” to
the repeater.
CTCSS and DCS are also used in areas that receive
interference where there are several stations with output
frequencies close to each other. When this occurs, you
might hear multiple communications on the same frequency.
The stations might even interfere with each other to the
point where it is impossible to clearly receive any of the
