2-Tone (Lmr) Signalling - Icom IC-F4062S Sales Handbook

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What is 2-Tone Signalling?
1. Originally called "Quick Call", this signalling protocol
was developed by Motorola in the 1950's.
2. 2-Tone (Quick Call) was designed to add Squelch
specificity especially for emergency service radios.
3. LMR consists of two distinct signals sent over the air
to a radio or a group.
4. Each tone can be configured within a 250 Hz and
3300 Hz tone frequency.
5. Normally, the duration of the tones varies from one
(1) to three (3) seconds in length no space between
the tones. Tone lengths of up to 10 seconds are
commonly seen in existing applications.
6. ICOM radios allow variable tone periods and spaces
(no tone) between the tones.
2-Tone Features
• "Selective Calling" – allows the dispatch console to
page an individual unit. Early models only allowed 1
(one) encoding tone set per channel or up to 3
(three) receive tones in the radio. Newer ICOM
radios allows the programming of up to 10 (ten)
tones that can be used all in one channel if
necessary.
• "Group Calling" - allows the dispatch console to
page a group.
• "Answer Back Call" – Also known as "Radio Check"
allows the dispatch console or another portable, to
send a tone to a particular radio and when the
target radio receives the tone it answers back with
another tone. This function serves as a tool to verify
if a unit is "ON" and within range.
• "Auto Transmit" – Also known as "Radio Spy" allows
the dispatcher to send a 2-Tone signal to the radio
causing it to open its transmitter microphone audio
(Hot Mic) in order to listen to whatever is happening

2-Tone (LMR) Signalling

LMR (2-Tone)‫‏‬
LMR (2-Tone)‫‏‬
✔
✔
LMR (LTR)‫‏‬
LMR (LTR)‫‏‬
LMR (Digital)‫‏‬
LMR (Digital)‫‏‬
PMR (5-Tone/DTMF)‫‏‬
PMR (5-Tone/DTMF)‫‏‬
BIIS PMR
BIIS PMR
1.
2.
3.
4.
in the proximity of the radio. This is also very useful in
emergency cases where the user may not be able to
trigger the microphone.
•"Stun/Kill – This function allows the dispatch
console to disable, temporarily or permanently, a unit
using the 2-Tone capabilities. When "Stun" is used,
the unit may regain its functionality by entering a
password. When Kill is used, the radio only regains
functionality by reprogramming the unit using the
cloning software.
•"Scan Start/Cancel" – Using 2-Tone a dispatcher
can send a signal to a radio or a group to commence
the "Scan" function of the radio. If used with a group
of users, this feature allows the dispatcher to
regroup everyone in a different, but common
channel. This feature is also known as "Radio
Regroup".
ICOM 2-Tone Radio Enhancements include:
RX Code Text – Allows the programmer to add an
"Alpha Numeric" text tag to each tone for
identification at decode and encode if the unit has a
display.
Variable Signals – This allows the user/programmer
to set the "Beep and Bell" to different formats for
easier identification when a signal is received.
Tones Assignable on a Channel by Channel Basis –
The newer Icom radios allow the programmer to
enter in ten (10) tone sets, which can be used for
both encode AND decode if necessary. Each channel
has the capability to use all tones for both encode
and decode, if programmed correctly.
Multiple Tone Sets per Channel – This also allows the
programmer to set all ten (10) tones on a single
channel if it was deemed necessary. Each channel
allows a programmer to use a combination of tones
per channel as needed.
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