Icom IC-M72 Service Manual page 12

4-6-1 CPU (MAIN UNIT; IC360)-continued
Pin Port
No. Name
104 BTYPE Input port for battery type detect signal.
Outputs MIC mute signal to the AF mute switch
(IC430, pin 13).
105 PTTM
"High": While transmitting.
"Low": While transmitting in VOX operation.
• While transmitting.
Outputs microphone sensitivity control signal to
the MIC gain controller (Q450, Q451).
(The microphone sensitivity is determinded by
MIC1/
106
the combination of "MIC1
SPCTRL
• While recseiving.
Outputs AF line switching signal to the analog
switch (IC430, pins 6, 12).
• While transmitting.
Outputs microphone sensitivity control signal
to the MIC gain controller (Q450, Q451).
MIC2/
107 • While recseiving.
AFVCTRL
Outputs AF power amplifi er (IC280 or IC401)
bias change signal to the AF amplifi er power
supply circuit (Q230, Q231, Q401, Q540).
• While transmitting.
Outputs microphone sensitivity control signal to
MIC3/ the MIC gain controller (Q450, Q451).
108
• While recseiving.
BPCTRL
Outputs AquaQuake function activate signal.
"Low": AquaQuake function is activated.
Input port for [SQL] key (RF UNIT; S250).
109 SQL
"Low": While [SQL] is pushed.
Input port for [ ] key (MAIN UNIT; S321).
110 UP
"Low": When [ ] key is pushed.
Input port for [ ] key (MAIN UNIT; S322).
111 DOWN
"Low": When [ ] key is pushed.
Input port for [CH/WX] key (MAIN UNIT; S324).
112 CH/WX
"Low": When [CH/WX] key is pushed.
Input port for [16] key (MAIN UNIT; S320).
113 16
"Low": When [16] key is pushed.
Input port for [SCAN] key (MAIN UNIT; S324).
114 SCAN
"Low": When [SCAN] key is pushed.
Input port for [H/L] key (MAIN UNIT; S329).
115 H/L
"Low": When [H/L] is pushed.
Outputs MIC mute signal to the AF mute switch
117 VOXM (IC430, pin 5).
"High": While transmitting.
Input port for PLL unlock signal ("UNLK") from
119 UNLK the PLL IC (IC1, pin 7).
"High": While the PLL is unlocked.
Description
− MIC3".)
4-6-2 D/A CONVERTER (RF UNIT; IC190)
Pin Port
No. Name
2 MODC Outputs deviation adjust signal.
3 FCON Outputs reference frequency adjust signal.
10 PCON Outputs transmit power setting voltage.
Outputs attenuator (RF UNIT; D94) switching
11 ATTS signal.
"High"=The attenuator (RF UNIT; D94) is activated.
Outputs transmit power setting signal.
15 LOW "High"=TX power [High] or [Mid] is selected.
"Low"=TX power [LOW] is selected.
Outputs center frequency tracking voltage to the
22 T2CON
BPF (RF UNIT; D131, L97, C112
Outputs center frequency tracking voltage to
23 T1CON the BPF'S (RF UNIT; D130, L96, C104, C109,
C110).
4 - 5
Description
−
C116).