21
6.13 DTMF
DTMF is an in-band signaling method using dual sinusoidal signals for any given code. Originally developed for telephony
systems, it has proved a very versa
�
le tool in many other areas.
In two-way radio systems, DTMF is most commonly used for automa
�
on systems and remote control. A common example
would be in amateur radio repeaters where some repeaters are ac
�
vated by sending out a DTMF sequence (usually a simple
single-digit sequence).
The
Radioddity
GT-82
EU has a full implementa
�
on of DTMF, including the A,
B,
C
and
D
codes.
The
numerical
keys,
as
well
as
the
[*SCAN]
,
and
[# ]
,
keys
correspond
to
the
matching
DTMF
codes
as
you
would
expect.
The
A,
B,
C
and
D
codes
are
located
in
the
[MENU],
[
▲
]
,
[
▼
]
and
[EXIT/AB]
keys
respec
�
vely
(†).
To send DTMF codes, press the key(s) corresponding to the message you want to send while holding down the PTT key.
If you have the keypad lock enabled on your radio, you can s
till
send DTMF tones the regular way without having to
unlock your radio.
Chapter7. Working the MENU System
For a complete reference on available menu items and parameters, see
Appendix C, Shortcut Menu opera
�
ons.
Note: in channel mode, the se
�
ng of these features is not possible: CTCSS/ DCS tones, wide/narrow bandwidth, PTT-ID,
Busy channel lock out, channel name edit.
