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WHAT IS SEARCHING?
The BC125AT can search for active frequencies. This is dierent
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 nds an active frequency, it stops on that frequency
as long as the transmission lasts. If you think the frequency is
interesting, you can store it into one of the banks. If not, you can
continue to search.
UNDERSTANDING SCANNING
What is CTCSS/DCS?
Your scanner can monitor systems using a Continuous Tone
Coded Squelch System (CTCSS) and Digital Coded Squelch (DCS)
system, which allows the squelch to open only when the tone
you have programmed with a specic frequency is received
along with a transmission.
CTCSS and DCS are sub-audible 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 sub-audible
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.
