Kenwood NX-840, Service Manual

Page: 19 / 54

(No.RA011<Rev.001>)1-19
2.7 TERMINAL FUNCTION
2.7.1 Display unit (X54-3890-20)
Q710 Transistor 9T switch
Q711 Transistor 5C control switch
Q712 Transistor Overvoltage detect
Q713 Transistor Overvoltage detect
Q714,
Q715 FET Speaker mute switch
Q716 Transistor 5C switch
Q717 FET 33BA switch
Q718 Transistor SB control switch
Q719 FET SB switch
Q720 Transistor AF amp switch
Q721 FET 5MS switch
Q722 Transistor 5MS control switch
Q723 Transistor 33BA control switch
D5 Variable
Capacitance Diode TX VCO tune
D6 Variable
Capacitance Diode TX VCO tune
D7 Variable
Capacitance Diode RX VCO tune
D8 Variable
Capacitance Diode RX VCO tune
D9 Variable
Capacitance Diode TX VCO tune
D10 Variable
Capacitance Diode TX VCO tune
D11 Variable
Capacitance Diode TX VCO tune
D12 Variable
Capacitance Diode RX VCO tune
D13 Variable
Capacitance Diode RX VCO tune
D14 Variable
Capacitance Diode RX VCO tune
D15 Variable
Capacitance Diode Modulation Control (TX VCO)
D16, D17 Diode TX/RX band switch
D300 Zener Diode Voltage Protection
D301 Diode TX power control
D304 Diode Reverse power rectifier
D305,
D306 Diode ANT switch
D307,
D308 Diode Power rectifier
D309,
D310 Diode ANT switch
D500 Diode Squelch voltage rectifier
D502~
D505 Variable
Capacitance Diode RF BPF tuning
D700~
D702 Diode Surge protection
Ref. No. Part Name Description
D704~
D711 Diode Surge protection
D712,
D713 Diode MIC AGC detection
D714,
D715 Diode RXD2 level shifter
D717 Zener Diode Voltage Protection
D718 Diode 5M stabalize
D719 Surge Absorber Voltage Protection
D720 Diode PTT
D721 Diode Hook
Pin
No. Name I/O Function
CN1
1 POWER O Detection output of power switch
2 MKEY I/O MIC data detection
3 PTT/TXD I/O PTT/PC serial data
4 HOOK/RXD I/O HOOK/PC serial data
5 ME - MIC ground
6 MIC O MIC signal output
7 GND - Ground
8 NC - -
9 LELH I LED latch input
10 LECL I LED clock input
11 LECE I LED enable input
12 LEDI I LED data input
13 5C I 5V DC power supply
14 KMI3 O Key matrix output 3
15 KMI2 O Key matrix output 2
16 KMI1 O Key matrix output 1
17 KMO3 I Key matrix input 3
18 KMO2 I Key matrix input 2
19 KMO1 I Key matrix input 1
20 BLED I Blue LED control signal input
21 GLED I Green LED control signal input
22 RLED I Red LED control signal input
23 MBL I MIC backlight control signal
input
24 LEDM I LED dimmer input
25 SP- I Speaker input -
26 SP- I Speaker input -
27 SP+ I Speaker input +
28 SP+ I Speaker input +
29 SB I Battery voltage DC supply
30 SB I Battery voltage DC supply
Ref. No. Part Name Description