![background image](http://html.mh-extra.com/html/icom/ic-2820h/ic-2820h_service-manual_612070016.webp)
4 - 10
PIN
No.
PORT NAME
DESCRIPTION
I/O
100
RESET
Reset enable signal input.
I
101
L_SQL
Noise signal from the IF IC (Left band;
IC15).
I
102
CL_SFT2
Clock frequency shifting signal.
O
105
R_SQL
Noise signal from the IF IC (Right band;
IC18).
I
122
R_DATA
Data lines for the control unit.
I
123
TX_DATA
Data lines for the control unit.
O
127
TX232
Data bus for RS-232C communication.
O
128
RX232
Data bus for RS-232C communication.
I
129
DA_CK
Serial clock signal to the D/A converter.
O
130
DA_DATA
Serial data to the D/A converter.
O
134
DA_STB
Strobe signal to the D/A converter.
O
135
R_R5C
RX circuits (Right band) control signal.
O
136
R400_S
Power line control signal to the 375−550 MHz
band RF circuit (Right band).
O
137
R_RX800
Power line control signal to the 810−1000
MHz band RF circuit (Right band).
O
138
R_AMC
AM-demodulator circuit (Right band)
control signal.
O
143
DTMSD
Data to the DTMF decoder (IC56).
-
144
DTMCK
Clock signal to the DTMF decoder (IC56).
-