Uniden BCD396T Scanner User Manual


 
20
Understanding Scanning
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 BCD396T can search each of its 12 bands and up
to 10 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 scan-
ner finds an active frequency, it stops on that fre-
quency 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 Continuous
Tone Coded Squelch System (CTCSS) and Digital
Coded Squelch (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
BCD396T Paper OM.fm Page 20 Wednesday, March 30, 2005 8:36 PM