Description Of Components - Kenwood TH-28A Service Manual

TH-28A/E
DESCRIPTION OF COMPONENTS |
CONTROL UNIT (X53-340X-XX) 0-11:K,P 0-21:M 0-22:M2 0-71:X 2-71:E,E3,E6,T 2-72:E2
Ref. No.
Use/Function
Operation/Condition/Compatibility
IC2 DTMF receiver
IC3 Voltage detection
IC4 Shift register
IC5 EEPROM for memory
IC6 Microprocessor
Qi Constant-current source for lamp
Q2 Lamp switch LAMP "H* : On
Q3 DC SW Always on
4 Reset output
Q5 DC SW IC5 power supply
Q201 Constant-current circuit Charging
D1, D2 LED LAMP
D3 Constant-current setting
D4 Reverse-flow prevention
D5 Microprocessor power supply
D6 Lithium battery charging
D7 Microprocessor noise removal
D8~D15 For destination
D16, D17 Reverse-flow prevention
Di8 Receive shift voltage switching
--B4-9-———-------}+--Electrostatic-surge- prevention
D201~D203 | Reverse-flow prevention
D224 Constant-current circuit
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