2
TMAA02-02 DTMF Microphone
© Tait Limited November 2012
Installing the Microphone Clip
1 Install the microphone clip in the most convenient location for the radio user. It must be
within easy reach of the user, but in such a position that the microphone PTT key can-
not be inadvertently activated or jammed on.
2 Connect the microphone clip to the negative supply, if hookswitch operation
is required.
Adjustment
Remove the DTMF microphone back cover and set the DTMF tone level to approximately
60% deviation (±3kHz for wide bandwidth radios and ±1.5kHz for narrow bandwidth
radios).
Radio Programming
The following table shows the settings required for CH_GPIO1 in the Programmable I/O
form of the programming application. When CH_GPIO1 is set to
Send Mic Audio To Spkr
,
then DTMF tones are fed into the radio’s speaker at a reduced volume whenever a key on the
DTMF microphone is pressed. This gives the radio user confidence that the tones are being
transmitted. Refer to the online help of the programming application for more information.
More Information
Refer to your radio provider for more information about this product.
Correct DTMF microphone grommet seating
DTMF microphone settings in the Programmable I/O form, Digital tab
Pin
Direction
Label Action
Active Debounce Signal State
Mirrored To
CH_GPIO1 Input
None Send Mic Audio
To Spkr
High
None
None
None
microphone
grommet
control head
