User's Manual

Shenzhen Friendcom Technology Development Co., Ltd.
Table 1
Internal bridge Internal modem
CON-14-PIN1
TFSK GND
CON-14-PIN2
RXD(RADIO) RXD(MODEM)
CON-14-PIN3
EXT_PTT EXT_PTT
CON-14-PIN4
TXD(RADIO) TXD(MODEM)
CON-14-PIN5
RFSK CD_OUT
CON-14-PIN6
TFSK NC
CON-14-PIN7
EXT_PTT NC
CON-14-PIN12
GND GND
CON-14-PIN14
NC
+12V（B+/9.6～16V DC）
3.1 Pin Assignment
As to FC-302V with 4FSK modem, the pin assignment is shown in Table 2.
Table 2
Pin Name Pin No. Description Remark
AUDIO_IN
（MOD IN）
1
Audio input. 3KHz LPF,
Modulation sensitivity is 100mV.
AUDIO_IN is effective only when PIN
7(MIC) is vacant or with +5V high level.
3KHz LPF filter existed in audio channel.
AUDIO_OUT
（AF OUT）
2
Audio output, 3Khz LPF. Output level
at 60% frequency deviation is
250±50mV. This line has an internal
pull
-up resistor to +5V.
PTT 3
TX control, active low, only when PTT
is active AUDIO_IN and MIC IN are
effective. This line has an internal pull-
up to 5V.
B+
(9.6～16V DC)
4
Positive pole input from DC power,
nominal +12V.
PROG
(DATA OUT)
5 Programming data output, 5V TTL
BUSY 6
Logical level output to indicate whether
there is a carrier or not. Low lever =
carrier, high level=no carrier. This line
has a pull-up to +5V.
MIC IN/RSSI 7
MIC IN: Microphone input.
RSSI: To detect the air signal strength.
Jumper selectable.
Can directly connect to electrets MIC, the DC
voltage of this pin should lower than 3.5V,
then MIC transmission can be activated.
PROG
(DATA IN)
8 Programming data input, 5V TTL
SPK/
POCSAG
9
SPK: Audio output from the audio
amplifier, @ 8Ω.
POCSAG:
To transmit POCSAG code.
Jumper selectable.
AUDIO_IN is effective only when PIN
7(MIC) is vacant or with +5V high level.
3KHz LPF filter existed in audio channel.
RXD
（MODEM）
10
The serial data is input to modem
through this pin. Default is RS232.
The hardware is one of RS232, RS485 or
TTL/5V when delivery.
TXD
（MODEM）
11
Serial data is output from modem via
this pin. Default is RS232.
The hardware is one of RS232, RS485 or
TTL/5V when delivery.
CD_OUT
(MODEM)
12
Logical level output to indicated
whether a carrier or not. Low lever =
carrier, high level=no carrier.
NC 13
GND 14 Ground
NC 15
6