Tait tm8200 Accessories Manual

TM8100/TM8200 Accessories Manual TMAA02-02 DTMF Microphone 55
© Tait Electronics Limited August 2005
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5.5 Circuit Description
The microphone has a standard 12-key telephone keypad. When one of the
keypad keys is pressed, a DTMF tone specific to that key is generated on the
MIC_AUD line (pin 5). For the duration of the tone, the tone generator
activates the PTT, so that the user is not required to press the PTT key to
transmit each tone.
Figure 5.2 DTMF microphone to radio interface

Tait tm8200 Specifications

General

Operating Temperature Range	-30°C to +60°C
IP Rating	IP54
Channel Spacing	12.5 kHz, 25 kHz
Battery Life	N/A (Mobile Radio)
Frequency Range	136-174 MHz, 400-470 MHz