Component Description - Kenwood KRC-225 Service Manual

¶
SWITCH UNIT(X16-1490-XX)
Ref.No. Component Name
IC1 LC75853NE
DTA114EK or UN2111
Q1
or KRA102S
¶
SYNTHESIZER UNIT(X14-6850-XX)
Ref.No. Component Name
IC1 LC72366-9592
IC2 TDA7461ND
IC3 HD74HC27FP
TDA7384A or
IC4
TDA7386
IC5 LA3161
2SC2412K or
Q50
2SD601A
Q51 2SB1443
2SC2412K or
Q52
2SD601A
DTA114YK or UN2114
Q53
or KRA107S
DTC144EK or UN2213
Q54
or KRC104S
DTA124EK or UN2112
Q55
or KRA103S
2SA2057 or 2SB1548
Q56 (P) or 2SB1565(E,F)
or 2SB1655(E,F)
2SC2412K or
Q57
2SD601A
DTC144EK or UN2213
Q58
or KRC104S
DTA124EK or UN2112
Q59
or KRA103S
2SA2057 or 2SB1548
Q60 (P) or 2SB1565(E,F)
or 2SB1655(E,F)
2SC2412K or
Q61
2SD601A
DTC124EK or UN2212
Q150
or KRC103S
DTC114YK or UN2214
Q151
or KRC107S
DTA124EK or UN2112
Q153
or KRA103S
DTC124EK or UN2212
Q200
or KRC103S
Q201 2SB1277(Q,R)
DTC124EK or UN2212
Q202
or KRC103S
Q203 2SB1277(Q,R)

COMPONENT DESCRIPTION

Application/Function
LCD driver with key-matrix
Key-matrix permission SW Ready on key-matrix
Application/Function
System MI-COM.
E-VOL. & N.C. MPX
Mute logic
Power IC
Equalizer amplifier
BACK-UP detection
(Momentary power down
detection) SW
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
Pre-out mute driver
FM +B SW
AM +B SW
KRC-225/235/265/265S
Operation/Condition/Compatibility
Operation/Condition/Compatibility
System control
Controls sound volume. Selects each source.
3-input NOR gate x 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
turned on.
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.
When BACK-UP detection SW or CHANGER RESET SW or
MI-COM.'s mute works, a base becomes Lo, and Q153
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.
3