Components Description - Kenwood KRC-20SA Service Manual

SWITCH UNIT (X16-1492-XX)
Ref.No. Component Name
IC1 LC75853NE
DTA114EK or UN2111 or
Q1
KRA102S
SYNTHESIZER UNIT (X14-6852-71)
Ref.No. Component Name
IC1 LC72366-9592
IC2 TDA7461ND
IC3 HD74HC27FP
IC4 TDA7384A
IC5 LA3161
Q50 2SC2412K or 2SD601A
Q51 2SB1443
Q52 2SC2412K or 2SD601A
DTA114YK or UN2114 or
Q53
KRA107S
DTC144EK or UN2213 or
Q54
KRC104S
DTA124EK or UN2112 or
Q55
KRA103S
2SA2057 or 2SB1548 (P) or
Q56 2SB1565(E,F) or
2SB1655(E,F)
Q57 2SC2412K or 2SD601A
DTC144EK or UN2213 or
Q58
KRC104S
DTA124EK or UN2112 or
Q59
KRA103S
2SA2057 or 2SB1548 (P) or
Q60 2SB1565(E,F) or
2SB1655(E,F)
Q61 2SC2412K or 2SD601A
DTC124EK or UN2212 or
Q150
KRC103S
DTC114YK or UN2214 or
Q151
KRC107S
DTC124EK or UN2212 or
Q200
KRC103S
Q201 2SB1277(Q,R)
DTC124EK or UN2212 or
Q202
KRC103S
Q203 2SB1277(Q,R)

COMPONENTS DESCRIPTION

Application/Function
LCD driver with key-matrix
Key-matrix permission SW
Application/Function
System MI-COM.
E-VOL. & N.C. MPX
Mute logic
Power IC
Equalizer amplifier
BACK-UP detection
(Momentary power down detection) SW turned on.
BACK-UP 5V AVR
P.ON 5V SW
COM+B SW
COM+B AVR
Illumination +B SW
Illumination +B driver
Electric volume mute SW
SVR discharge SW
FM +B SW
AM +B SW
KRC-20SA/G
Operation/Condition/Compatibility
Ready on key-matrix
Operation/Condition/Compatibility
System control
Controls sound volume. Selects each source.
3-input NOR gate × 3
Amplifies power so that the speaker can drive audio signal.
Equalizer amplifier for cassette tape sound
While BACK-UP is added, a base becomes Hi, and Q50 is
While BACK-UP is added, AVR outputs +5V.
Q51 and Q52 is inverted Darlington connection.
While a base becomes Lo, Q53 is turned on.
While Q54's base becomes Hi, Q55 is turned on.
Works during POWER ON mode.
While Q57's base becomes Hi, Q56 is turned on.
Q56 and Q57 is inverted Darlington connection.
While Q58's base becomes Hi, Q59 is turned on.
Works during POWER ON mode with a panel
attached to the set.
While Q61's base becomes Hi, Q60 is turned on.
Q60 and Q61 is inverted Darlington connection.
When BACK-UP detection SW or CHANGER RESET SW or
MI-COM.'s mute works, a base becomes Hi, and Q150
is turned on.
When POWER IC RESET is activated, a base becomes Hi,
Q151 is turned on.
Q201 is turned on when Q200's base becomes Hi.
Works during FM reception mode.
Q203 is turned on when Q202's base becomes Hi.
Works during AM reception mode.
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