Components Description - Kenwood 144MHz FM TRANSCEIVER K2E Service Manual

SEMICONDUCTOR DATA / COMPONENTS DESCRIPTION
Pin Pin
I/O
No. Name
DC IN detection interrupt input ( ↓ )
98 DCDET I
99 RXLED O Busy LED output
100 BSFT O Beat shift swiching output
101 PLLEN O Serial enable output to PLL IC
102 PLLLD I Lock detection input from PLL IC H: Lock
103 KIN0 I Key matrix input 0
104 KIN1 I Key matrix input 1
105 KIN2 I Key matrix input 2
106 KIN3 I Key matrix input 3
107 KIN4 I Key matrix input 4
108 TYPE I Market code bit input
109 VUKEY I Detection of 4 key or 16 key
110 MICM O Microphone mute switch
111 NOAA I 1050Hz tone detection input
112 5R O RX power supply switch
113 SHIFT O VCO shift switch
114 5T O TX power supply switch
115 KOUT0 O Key matrix output 0
116 KOUT1 O Key matrix output 1
117 KOUT2 O Key matrix output 2
118 KOUT3 O Key matrix output 3
119 VSS - GND
120 BTDET O Battery detection switch
Function
L:DC IN connected
H:ON
H:ON
H:Mute
L:ON
L:TX, H:RX
L:ON
L:ON
TH-K2AT/K2E/K2ET

COMPONENTS DESCRIPTION

TX-RX UNIT (X57-674X-XX)
Ref. No. Use/Function Operation/Condition/Compatibility
IC1 PLL IC
APC differential
IC2
amplifier
IC3 FM IC
IC4 11.5V AVR
IC5 HPF Active filter
IC6 AF amplifier
IC8 MPU
IC9 5.0V AVR
4.4V voltage
IC10 MPU INT voltage detection
detection
3.3V voltage
IC11 MPU Reset voltage detection
detection
IC12 5.0V AVR
IC15 EEPROM
IC16 MIC amplifier Limiter, splatter filter
CTCSS/DCS/WX
IC17 Active filter
filter
Q1 VCO
Q2 RF amplifier
VCO shift
Q3 On RX
control switch
Q4 Ripple filter
Q5,6,9 RF amplifier
Q10,11 Drive amplifier
Q12 Power amplifier
APC circuit
Q13 On TX
operation switch
APC output
Q14 On TX
switch
Q10 operation
Q15 On TX
switch
Q16 1st mixer
Q17 RX 1st amplifier
Audio mute
Q20 Audio mute when off
switch
Q21 Audio filter Active filter
Wide/narrow
Q22 On when wide is selected
changeover switch
Q23 Tripler 2nd local
Q24 IF amplifier 1st IF 38.85MHz
Wide/narrow
Q27 On when wide is selected
changeover switch
MIC mute
Q29 Mutes when ON
switch
VOX detection
Q30
amplifier
Q56 operation
Q31 Off when the speaker outputs audio
switch
Q33 Charge switch
15