Tait TM8100 mobiles, Service Manual

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508 TMAA02-02 DTMF Microphone TM8100/TM8200 Service Manual
© Tait Electronics Limited November 2007
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 cannot be inadvertently
activated or jammed on.
2. Connect the microphone clip to the negative supply if hookswitch
operation is required.
20.2 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).
20.3 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.
Figure 20.1 Correct DTMF microphone grommet seating
microphone
grommet
control head
Table 20.1 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