Kantronics MT1200, Руководство пользователя

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5 RXA Receive audio (AFSK in)
6 GND Ground
7 EXT-IN External input for microphone PTT
8 CTLA Control line A
9 GND Ground (same as pin 6)
Pin 1: Connects to the microphone input of your radio, providing the audio signal to be
transmitted.
Pin 2: When a ground is applied to this pin, the MT1200 will not transmit packets. This
pin is normally used as an external means of supplying carrier detect, but can also be
used as a “hardware” transmit inhibit.
Pin 3: When the MT1200 needs to key your transmitter, it will apply a ground to this pin.
This is an open-drain circuit and requires a positive voltage from your radio (not to
exceed 60 V dc or 115 mA).
Pin 4: This pin is the CONTROL B output from the MT1200 which may be used as a
control line to your radio or other devices. It is an open-drain circuit, and will apply a
ground on this pin when controlled by the CTRL command in your MT1200 (not to
exceed 60 V dc or 115 mA).
Pin 5: Receive audio from your radio connects to this pin. This normally will connect to
the external speaker jack on your radio, but may be connected to the receive audio
output pin on your microphone connector (if available).
Pin 6: This pin connects to the ground of your radio mic connector.
Pin 7: This pin is an input, that is used for sensing the PTT from your microphone to the
radio.
Pin 8: This pin is the CONTROL A output from the MT1200 which may be used as a
control line to your radio or other devices. It is an open-drain circuit, and will apply a
ground on this pin when controlled by the CTRL command in your MT1200 (not to
exceed 60 V dc or 115 mA).
Pin 9: This pin connects to ground, same as pin 6.
Interfacing Hand-Held Radios
This section is for those who need more information than that given in the “Installation”
chapter.
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