Kenwood TH-77A Service Manual page 73

TH-77A/E
TERMINAL FUNCTIONS
Pin Functions
Pele |=m| em
Control unit (X53-333X-XX)
CN1 = CN1 (TX-RX unit RFV: X57-3630-XX)
CN1 DP VHF PLL circuit serial transmission data line
ULV VHF PLL unlock detection
CK VHF PLL circuit serial transmission clock line
AFV VHF (sub-UHF) audio output
EV VHF PLL circuit enable line
Receiver block 5 V power supply
12.8 12.8 MHz PLL reference oscillation input
VHF modulation
SRVC | Receiver common 5 V power supply
5CV PLL common 5 V power supply
SMV | VHF/sub-UHF signal strength meter output
SCV Receiver busy signal (Low when squelch is
open.)
SQV Squelch noise detection DC output
5RV VHF receiver block 5 V power supply
APC APC control line
GND Ground
APC power selection logic line
Line B
APC power selection logic line
VHF transmitter 5 V power supply
APC daughter selection switch power supply
Control unit (X53-333X-XX)
CN2 = CN201 (TX-RX unit RFU: X57-3630-XX)
OMNODORWH =
CN2 PLL common 5 V power supply
UHF modulation
12.8 MHz reference oscillation output
Input from external power pin
UHF PLL unlock detection
UHF 360/800 AF output
UHF PLL circuit serial transmission clock line
UHF PLL circuit enable line
UHF receiver block 5 V power supply
UHF PLL circuit serial transmission data line
UHF/360/800 signal strength meter output
PLL common 5 V power supply
Squelch noise detection DC output
800 5 V power supply
UHF/800 common 5 V power supply
Ground
Ground
Receiver busy signal (Low when squelch is
open.)
Line B
UHF transmitter block 5 V power supply
UHF APC control line
OMNOAOARWH
Control unit (X53-333X-XX)
Tone signal output
2 E Ground
3 SDO | Tone signal coincidence discrimination signal
(High: Coincides)
4 DP Data signal
5 cP Clock signal
6 5C 5 V power supply
7 DT Tone serial data
8 Audio signal input
9 Tone enable
Ground
VHF signal input/output
Ground
APC power detection line B
Sub-receive signal
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