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4 - 5
4-7-2 MAIN CPU (MAIN unit; IC17)
Outputs serial data signal for EEP-
ROM (IC17).
Outputs select signal to the analog
switch (IC12) for the microphone audio
signal or DSC signal.
D/A output port for the ATIS/DSC
encode signal to the buffer amplifier
(Q33).
Input port from the FM IF IC (IC1) for
the squelch operation.
Input port for the connected power
supply voltage detection (low battery
indicator).
Input port for the “TX” indicator from
the power detector circuit (D14, D15).
Input port for the ATIS/DSC decode
signal.
Input port for the PLL unlock signal.
Low : While PLL is locked.
Input port for the communication data
from DS-100 via the DSC connector
(DSC unit; J1), photo coupler (DSC
unit; IC2) and buffer amplifier (DSC
unit; IC3).
Outputs the communication data to
DS-100 via the buffer amplifier (DSC
unit; Q1, Q2, D4).
Input port for the PTT switch.
Input port for the microphone hanger
detection signal.
Low : Microphone on hook
Input port for the optional unit connec-
tion detection.
Outputs the R8 regulator (Q22, Q23)
control signal.
Low : While receiving
Outputs the AF mute switch (Q26)
control signal for main body.
Low : While squelched
Outputs the AF mute switch (Q27)
control signal for the optional remote
microphone (HM-127).
Low : While squelched
Outputs beep audio for main body.
Outputs beep audio for the optional
remote microphone (HM-127).
Input port for the reset signal.
Outputs the reset signal for sub CPU
(LOGIC unit; IC1).
EDA
MICDSC
DSC
SQL
LBAT
TXDET
DSDEC
UNLK
DATAS
DATAM
PTT
HANG
OPTIN
RCV
RMUTM
RMUTS
BEEPM
BPLVM
RESET
SRESET
24
27
30
39
42
44
45
46
57
58
60
61
62
66
67
68
69
71
75
100
1
2
3
4
5
6
7
8
10
11
12
13
14
15
16
17
19
20
23
STRU
SCON
OPSTB
PSTB
CK
DATA
PTTM
PTTS
MMUTE
SMUTE
SP
HI/LO
SEND
TMUTE
SRXD
STXD
CLRX
CLTX
ECK
Outputs control signal to the analog
switch (IC12) for passing through the
optional VOICE SCRAMBLER unit
(UT98 or UT-112).
Outputs ON/OFF control signal for the
optional VOICE SCRAMBLER unit
(UT-98 or UT-112).
Outputs strobe signals for the optional
VOICE SCRAMBLER unit UT-98 or
UT-112.
Outputs strobe signals to PLL IC (IC2,
pin 2).
Outputs clock signal to PLL IC (IC2,
pin 3).
Outputs clock signal to PLL IC (IC2,
pin 4).
Outputs main microphone (HM-126)
select signal to the analog switch
(IC10) while intercom operation.
Outputs optional remote microphone
(HM-127) select signal to the analog
switch (IC10) while intercom operation.
Outputs select signal for the speaker
of main microphone (HM-126) to the
analog switch (IC10) while intercom
operation.
Outputs select signal for the speaker
of optional remote microphone (HM-
127) to the analog switch (IC10) while
intercom operation.
Outputs ON/OFF control signal for the
internal speaker to the AF mute circuit
(Q32, D23, RL2).
Low : While internal speaker is ON.
Output port for RF output power (High
or Low) select signal.
Low : While low power is selected.
Outputs the T8 regulator (Q20, Q21)
control signal.
Low : While transmitting
Outputs transmit mute signal.
High : While transmitting
Input port for the communication data
from sub CPU (LOGIC unit; IC1).
Outputs communication data for sub
CPU (LOGIC unit; IC1).
Input port for the cloning data from the
buffer (D24).
Output port for the cloning data to the
buffer (MAIN unit; Q37).
Outputs clock signal for EEPROM
(IC17).
Pin
Port
Description
number
name
Pin
Port
Description
number
name