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Each receive mode affects how your scanner operates when scanning and receiving
transmissions.
Note
•
Trunked modes (ED and MOT) can only be selected for frequencies above 137 MHz.
•
Your scanner’s Closed Mode lets you hear transmissions from only those trunking
talkgroups you specify. For more information, see “Open and Closed Mode
Operation” on Page 83.
AM Mode (AM)
The AM mode sets the scanner to receive transmissions using amplitude modulation
(AM), primarily used for aircraft, military, 27 MHz citizen’s band, some amateur radio,
and some government transmissions. (Refer to “SPECIFICATIONS” on Page 107 for a
list of the frequencies covered.) When the scanner receives a transmission on a channel
set to the AM mode, it always stops on the transmission.
FM/Digital Mode (FM)
The FM/Digital (FM) mode sets the scanner to receive transmissions using frequency
modulation (FM) and APCO-25 digital modulation. FM is used for most public safety
transmissions, as well as broadcast, business, and amateur radio transmissions.
APCO-25 digital modulation is used in many newer conventional and trunked public
safety radio systems. When the scanner receives a transmission on a channel set to the
FM/Digital mode, it always stops on the transmission.
CTCSS Mode (CT)
CTCSS mode sets the scanner to receive transmissions using frequency modulation
(FM) with Continuous Tone Coded Squelch System (CTCSS) subaudible tone codes.
CTCSS allows multiple users to share a single radio frequency without hearing each
other’s transmissions. In your PRO-96 scanner, the CTCSS feature can be used to block
the reception of transmissions on shared channel to only those that use the CTCSS tone
that you have specified. CTCSS mode also features a Code Search setting that allows
you to instantly display and store unknown codes into the channel memory. CTCSS
tones can sometimes be heard as a low “hum” in the background of a voice transmission.