User's Manual

VISIT!BAOFENGTECH.COM!AND!MIKLOR.COM!FOR!DOWNLOADS!AND!HELP! 41!
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C
hapter!8.!-!DTMF!
DT
MF!is!an!in-band!signaling!method!using!dual!sinusoidal!signals!for!any!given!co de.!Originally!
developed!for!telephony!systems,!it!has!proved!a!very!versatile!tool!in!many!other!areas.!
!
In!tw
o-way!radio!system s,!DTMF!is!most!common ly!used!for!automation!systems!and!remote!
control.!A!co mm on !example!would!be!in!amateur!radio!repeaters!where!some!repea ters!are!
activated!by!sending!out!a!DTMF!sequ ence!(u su ally!a!simple!single-digit!sequence).!
!
Table!8.1.!DTMF!fre q u en c ies !an d !co rr e sp o nd in g !co d es!
!
!
1209!
Hz!
1336!
Hz! 1477!Hz!
1633!
Hz!
697!
Hz! 1!
2! 3!
A!-! !
770!
Hz! 4!
5! 6!
B!-! !
852!
Hz! 7!
8! 9!
C!-! !
941!
Hz! *!
0! #!
D!-! !
!
Th
e!BTECH!MURS-V1!has!a!full!im p lementa tio n !of!DTMF,!including !the!A,!B,!C!and!D!codes.!
!
Th
e!numerical!keys,!as!well!as!the! ,!and! ,!keys!correspond!to!the!matching!DTMF!codes!as!
you!would!expect.!The!A,!B,!C!and!D!codes!are!located!in!the! ,! ,! !and! !keys!