User's Manual

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KNG User’s Manual
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RELM/BK Radio
NOTE: When using a channel programmed for mixed mode transmit
the signal will be transmitted in the mode selected by the TX Digital
selection. Or if programmed for Mixed Mode Talkback, the radio will
transmit in the mode of the last received channel while the “RX” icon
is displayed. (See Mixed Mode Operation.)
Code Guard Operation
Analog Squelch Control
Sub-audible signaling (CTCSS/CDCSS) is used to allow a group of
radios to be selectively called in an analog system. Programming the
receive code guard equal to zero allows for Carrier Squelch operation,
where the radio will unmute whenever a carrier is detected regardless
of the transmitted Code Guard.
APCO Project 25 Squelch Control
Network Access Codes (NACs) provide the digital equivalent of analog
sub-audible signaling (CTCSS/CDCSS) allowing a group of radios to
be selectively called within a system.
Users in the same area (using the same NAC) can be further divided
into Talk Groups, with each group having its own Talk Group ID
(TGID). Group Calls are made by designating both the users’ NAC
and TGID.
Each radio also has an individual P25 unit ID. A Unit-to-Unit call
contains the addressee’s NAC, and uses the addressee’s P25 unit ID
instead of the TGID.
When operating in Digital Mode, each channel can be programmed to
use either Normal squelch or Selective squelch.
Normal squelch is used to mimic analog operation. Signals are
only qualiÞ ed with the programmed NAC. TGIDs and P25 Unit IDs
are ignored. Each digital channel is programmed with a receive NAC
and a transmit NAC. When an incoming signal’s NAC matches the
channel’s programmed receive NAC, the radio unmutes. The default
NAC is 0659 ($293 hex).
The digital equivalent of carrier squelch is achieved by programming
the receive NAC = 3966($F7E hex). The radio will unmute when a
digital signal with any NAC is detected. The 3966 ($F7E hex) NAC is
reserved for receivers and is not allowed as a transmit NAC.
Selective squelch is used for processing Group Calls and Unit-to-
Unit Calls. TGIDs are assigned on a per-channel basis. Users can
be separated into Talk Groups with each group having its own TGID.
Then, on channels programmed for Selective squelch, the incoming
signal’s NAC and TGID must match the channels programmed
receive NAC and TGID for the radio to unmute. The default TGID
is 1.
The TGID value 65535 ($FFFF hex) is used to effect an “All Call”.
If the radio receives a signal with a matching NAC and the TGID =
65535 ($FFFF hex), it will unmute. Also, if the radio’s programmed
TGID is 65535 ($FFFF hex), it will open on any signal with a matching
NAC, ignoring the incoming TGID. A TGID = 0 means “no one”. If
the radio is programmed with the TGID = 0, it will accept incoming
group calls containing the “All Call” TGID, and correctly addressed
Unit-to-Unit calls only.
Code Guard Receive
Analog channels programmed with a receive code guard will be heard
only when the proper frequency and Code Guard value is received.
Analog and mixed mode receive channels will also unmute when the
radio is in monitor mode.
Code Guard Transmit
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SCAN
PRI
VOL
Busy Channel/Transmit
Indicator
Ch 1
KNG-P150 P25
171.58500 MHz
LIGT T/A MENU LCK
TX
The frequency must be clear prior to transmitting
on a Code Guarded channel. If the LED Indicator
is yellow do not transmit. Busy Channel Lockout
can be programmed to disallow transmitting while
a channel is busy.
1. Press the PTT switch. When the transmitter is
on, the LED Indicator glows red and TX appears
in the display.
2 Talk in a normal voice with the microphone one
to two inches from your mouth.
3. Release the PTT switch to stop transmitting.