Kenwood TK-480 User Manual
23
TK-480/481
DESCRIPTION OF COMPONENTS
DISPLAY UNIT (X54-3210-XX)
Ref. No.
Use/ Function
Operation/Condition
IC300
IC
Audio power amplifier
IC301
IC
Counter
/ Key scan
Q300
FET
DC switch
/ INT MIC on/off
Q301
FET
DC switch
Q302
Transistor
DC switch
/ LED (Red) driver
Q303
Transistor
DC switch
/ LED (Green) driver
Q304
Transistor
DC switch
Q305
Transistor
Current driver
/ Audio amp AVR
Q306
Transistor
DC switch
Q307
Transistor
Current driver
/ LCD back light LED AVR
Q308
FET
DC switch
/ SP INT/EXT
Q309
Transistor
Temperature compensation
Q310
FET
Mute switch
D300
Zener diode
Surge absorption
D301
LED
LED
/ Red, Green
D302
Diode
Quick discharge
/ AF mute
D303
Zener diode
Voltage reference
D304
Diode
Voltage reference
D305~310
LED
LCD back light
D315~318
Diode
Reverse current prevention
D319~321
Zener diode
Surge absorption
Ref. No.
Use/ Function
Operation/Condition
IC15
IC
Microprocessor
/ 16-bit+1M flash
IC16
IC
EEPROM
IC17
IC
AND gate
IC18,19
IC
Shift register
/ Output expander
IC21
IC
Comparator (APC)
IC23
IC
Active filter
/ For HSDout
IC30
IC
Power module
Q1
FET
DC switch
/ 5R
Q2
Transistor
DC switch
/ 5T
Q3
Transistor
Ripple filter
/ 5CV
Q4
Transistor
TX/RX switch
Q5
Transistor
IF amplifier
Q6
FET
Mixer
Q7
FET
Mute switch
/ MIC line mute
Q8
Transistor
RF amplifier
Q9
FET
RF amplifier
Q10
Transistor
Buffer amplifier
Q11,12
Transistor
RF amplifier
/ TX driver
Q13
FET
DC switch
Q14,15
Transistor
DC switch
Q16
Transistor
AF mute switch
Q17
Transistor
RF amplifier
Q18
FET
DC switch
Q19
Transistor
Noise amplifier
/ Squelch
Q20
Transistor
Switch
Q21
FET
AF mute switch
Q22
FET
DC switch
Q23
FET
Mute switch
D1
Diode
Reverse protection
D2
Diode
Overload protection
D3
Diode
Noise detection
D4,5
Diode
TX/RX switch
D6
Diode
Overload protection
D7
Diode
ANT switch
D8
Diode
Reverse current prevention
D9,10
Diode
ANT switch
D11
Diode
Voltage clamp
D12
Diode
DC switch
D17,18
Diode
Surge absorption
TX-RX UNIT (X57-5630-XX)
Ref. No.
Use/ Function
Operation/Condition
IC1
IC
Buffer amplifier
IC2
IC
Voltage detector
/ Reset
IC3
IC
Summing amplifier
IC4
IC
D/A converter (Adjustment)
IC5
IC
Voltage regulator
/ 5M
IC6
IC
Voltage regulator
/ 5V
IC7
IC
Voltage regulator
/ 5C
IC8
IC
Buffer amplifier
IC9
IC
FM IF system
IC10
IC
Active filter
/ For LSDin
IC11
IC
PLL system
IC12
IC
Audio processor
IC13
IC
DTMF decoder
IC14
IC
VCO system