Kenwood KRC-794/Y User manual

©2002-12 PRINTED IN JAPAN
B53-0012-00 (N)1874
KRC-794
MTL/M.RDM
PROG/PTY
EX
50Wx4
DOLBY B NR
B NRLOUD SCAN B.S/RDM REP
DISP
NAME.S
TI
VOL ADJ
OFF AUD
MENU
CLK
ANG
DAB
DC cord
(E30-4942-05)
Plastic cabinet assy
(A02-1497-13) Lever (D10-4562-04)x2 Torsion coil spring (G01-2924-04) Remote controller assy (A70-2025-05) Mounting hardware assy (J21-9716-03)
Remote controller assy
(A70-0886-15) Antenna adaptor (T90-0523-05) Screw set (N99-1704-05)
MASK-key
RC-410
Knob(1-6)
(K25-1405-12)
Knob(VOL)
(K25-1404-13) Knob(UP,DW) (K25-1408-03) Front glass (B10-4222-03)
Front glass
(B10-4398-01) Knob(SRC)
(K24-3835-04)
Knob(FM,AM)
(K25-1406-03)
Panel assy
(A64-3030-02) Knob(PROG)
(K25-1407-03)
CASSETTE RECEIVER
KRC-794/Y
SERVICE MANUAL
The CASSETTE MECHANISM OPERATION DESCRIPTION is the same model D40-1122-05.
Please refer to the service manual for model D40-1122-05(B51-7542-00).
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TEL [phone] QQ 376315150 892498299 TEL [phone] QQ 376315150 892498299

KRC-794/Y 2
BLOCK DIAGRAM
ILL
TEL MUTE
ACC
ANT CON
P CON
BACK UP
EXT AMP CONT
FM+B
BUFFER
BUFFER
DECODER
RDS
IC11
IC2
E-VOL
MPX
N.C.
AM+B
SYSTEM u-COM
IC1
KEY
MATRIX
RESET
SW LCD DRIVER
REMO
G/R SW
RESET
IC15
MOTHER u-COM LCD TYPE
IC1
DRIVER
SUB MOT
IC13
MAIN MOT
AVR
SUB MOT
AVR
ILL AVR
A 8V
IC3 SW14V
EXT AMP CONT
DIMMER
ACC DET
TEL MUTE
P CON
B.U DET
ANT CON
SW5V B.U.5V
P-5V Q21,22
SRM
MECH
POWER IC
THERMO
PROTECT
IC4
IC10
MUTE LOGIC
DRIVER
MUTE
Q1-4
SP OUT
1.8V PRE OUT
LCD
ANT.
DET
SRM MECH
IC2
Q39
Q32
Q45
Q25
Q26,27
Q28-31
Q24
Q23
Q36
Q33,34
Q37,38
Q41,42
Q3,4
Q73
Q90
Q88
Q89
AUDIO
S-METER
IFC OUT
PLL DATA
PLL CLK
SW5V
FM
AM
TAPE
CHANGER
S METER
QUAL
SDA SCK S MUTE
A 8V
MODE 2
SUB-
MOT+B
SUB+
MODE 1
MS MODE
F/R
MUTE
MTL ON/OFF
BOLBY B/C
DOLBY ON/OFF
MS OUT
R REEL
F REEL
MODE 3
TAPE IN
SRM SW2 SRM SW1
RCLK
QUAL
RDATA
NOISE
S METER
IFC
IFC OUT
PLL DATA
PLL CLK
MS OUT
MTL ON/OFF
MODE 2
MODE 3
R REEL
MODE 1
F REEL
MS MODE
F/R
MUTE
DOLBY ON/OFF
DATA C
CH RST
CH MUTE
DOLBY B/C
DATA H
CH CON
CH CLK
REQ H
REQ C
TAPE IN
SRM DET RESET SUB MOT2 SUB MOT1 SUB MOT3 CASS/SRM MOTOR ILL ON
AM+B
FM+B
SCK
SDA
PRE MUTE
MUTE
BEEP
P MUTE
ACC DET
PHONE
DIMMER
EXT AMP CONT
P CON
P-5V
P ON
ANT CONT
B.U DET
SW5V
SW5V
3
3
13
CH MUTE
CH RST
DATA H
DATA C
CH CON
REQ C
CH CLK
REQ H
BACK UP
8
1200mV
388mV
A 8V
SW5V
PANEL5V
2
B.U.5V
4
2
SUB+
SUB-
2
SUB-
SUB+
MOT+B
A8V
PAN5V B.U.5VSW5V
MUTE AC GND
BACK UP
SW5V
B.U.5V
B.U.5V
CH
FM 1800mVTAPE
AM 3600mV 855mV
1372mV 600mV
3600mV
1800mV
E TYPE K TYPE
1800mV
SW5V
245mV(ETYPE)
460mV(KTYPE)
FM: AM:
170mV
TUNER
CASSETTE MECHA
CD-CHANGER
MD-CHANGER
(X16-154X-XX)
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KRC-794/Y
3
● SWITCH UNIT(X16-1540-12)
COMPONENTS DESCRIPTION
Component Purpose ¡Function Operation/Condition/Compatibility
IC1 LCD DRIVER with Key Matrix
IC2 Remote Control IC
Q1 Key Detection SW Q2 starts key scan in M&T.
Q3,4 Key Illumination SW Lights key illumination in Red when the base of Q3 is ON.
Lights key illumination in Green when the base of Q4 is "H"
Q5 VLCD Reference Voltage Supply Constant voltage circuit.
Q6 Remote Control IC Power Supply Activates remote control when the base of Q6 is "L".
Q7 Dimmer SW The base of Q7 is normally "H" but becomes " " when DIMMER is ON.
● DOLBY UNIT(X87-3022-71)
Component Purpose ¡Function Operation/Condition/Compatibility
IC1 Playback EQ, Dolby & Blank Detection
Q1 Constant Switching in Blank Detection Switches the time constant according to the PLAY or FF/REW mode.
● SYNTHESIZER UNIT(X14-6442-73)
Component Purpose ¡Function Operation/Condition/Compatibility
IC1 System µ-com
IC2 E-VOL, N.C, MPX
IC3 Regulator IC for Audio 8V
IC4 Power IC
IC10 Mute logic IC
IC11 RDS decoder
IC13 Motor driver IC
IC15 Reset IC
Q1~4 PRE OUT MUTE SW Pre outs are muted when the base goes "H".
Q18~20 Audio 8V AVR Inverted darlington connection
Q20 is turned ON when Q18's base goes "H".
Q21, 22 B.U 5V AVR Inverted darlington connection
Q22 is turned ON when Q21's base goes "H".
Q23 SW 5V ON when the base goes "L".
Q24 B.U detection ON when the base goes "H" during B.U applied.
Q25 ACC detection ON when the base goes "H" during ACC applied.
Q28~31 P-CON SW Q28 is turned ON when Q31's base goes "H".
Q32 Dimmer SW ON when the base goes "H" while vehicle small lamps turn on.
Q33,34,44 Illumination AVR ON when Q44's base goes "H".
Q36 SW 14V ON when base goes "H".
Q37,38 Motor driver supply Q38 is turned ON when Q37's base goes "H".
Q39 External Amp Control ON when the base goes "L".
Q41, 42 Cassette mecha main motor supply SW Q42 is turned ON when Q41's base goes "H".
Q43 Motor driver's voltage SW Base "H" ... cassette mecha's submotor
Base "L" ... mask mecha's motor.
Q45,46 Panel 5V SW Q45 is turned ON when Q46's base goes "H".
Q71 Pre out mute driver ON when the base goes "L".
Q72 E-VOL Mute SW ON when the base goes "H".
Q73 Noise buffer
Q85 IFC out buffer
Q86,88 AM+B SW Q88 is turned ON when Q86's base goes "H".
Q87,89 FM+B SW Q89 is turned ON when Q87's base goes "H".
Q90 Composite out buffer
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KRC-794/Y
MICROCOMPUTER'S TERMINAL DESCRIPTION
4
● SYSTEM MICROCOMPUTER UPD703033GC138 (IC1: X14-)
Pin No. Name I/O Description Processing Operation
1 AM+B O AM power supply terminal. During AM operation: H.
2 FM+B O FM power supply terminal. During FM operation: H.
Last FM with RDS model: H
3 AFS O Constant switching when noise is detected. During FM seek or AM search: L.
During reception: H.
4 PLL-DATA I/O DATA input/output terminal from/to F/E.
5 PLL-CLK I/O CLOCK input/output terminal from/to F/E.
6 Evdd - Positive power supply terminal.
7 GND - Grounding terminal.
8 N.C O No connection.
9 BEEP O Beep output terminal.
10 REMO I Remote control input terminal.
11 P-ON O SW 14 V control terminal. Power ON: H. Power OFF: L.
12 P-STBY O Power IC STBY terminal control. Power IC OFF: L. Power IC ON: H.
During reset: Input.
13 IC2-SDA I/O IC2 DATA line.
14 IC2-SCK O IC2 CLOCK line.
15 P-MUTE O Power IC muting terminal. Power OFF: L. All OFF: L.
During TEL muting: L.
16 PRE-MUTE O Pre-Out muting terminal. During momentary power down: L.
17 D/A-SDA/DIM-CON O D/A data line. (V-LED)
18 TEST - Test pin.
19 P-CON O Power control terminal. Power ON: H. Power OFF: L.
20 ANT-CON O Antenna control terminal. TUNER, TI ON: H
21 MUTE O Muting terminal. ON: Open. OFF: L.
The time constant is 0.48 ms with all models.
22 N.C O No connection.
23 ACC-DET I Acc detection terminal. Acc detected: L. Acc not detected: H.
24 DIMMER I Small detection terminal. ON: L. OFF: H.
25 SW-5V O 5 V power supply terminal. ON: L. OFF: H.
26 CH-MUTE I Muting request from CH. ON: H. OFF: L.
27 CH-CON O CH control output. ON: H. OFF: L.
28 CH-REQH O Request output to CH. Requested: L.
29 CH-RST O Reset output to CH.
Normal: L. When the system is reset, turns H then
L in 400 ms after recovery from reset.
30 EXT-AMP-CONT O External amplifier control terminal (In 200 ms). L 40 ms: Bass boost OFF.
L 70 ms: Bass boost LOW.
L 100 ms: Bass boost HIGH.
31 RESET I Reset input terminal. Normal: H. Reset: L.
32 XT1 I Sub-clock connection terminal. The clock count is active even when Power is OFF.
33 XT2 - Sub-clock connection terminal.
34 REGC -
Output terminal for the capacitor in the regulator
in µ-COM.
35 X2 - Main clock connection terminal. Power ON: Oscillated.
Power OFF or momentary power down: Oscillation stopped.
36 X1 I Main clock connection terminal.
37 Vss - Grounding terminal.
38 Vdd - Positive power supply terminal.
39 CLKOUT O Internal System Clock output.
40 N.C O No connection.
41 MOTOR O Cassette mechanism main motor output terminal.
When the motor is running: H.
When it is stopped: L.
42 MODE3 I Cassette mechanism mode detection terminal.
43 MODE1 I Cassette mechanism mode detection terminal.
44 MODE2 I Cassette mechanism mode detection terminal.
45 N.C O Outputs Low. No connection.
46 SUB1 O Sub-motor output terminal (1).
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KRC-794/Y
MICROCOMPUTER'S TERMINAL DESCRIPTION
5
Pin No. Name I/O Description Processing Operation
47 SUB2 O Sub-motor output terminal (2).
48 SUB3 O Sub-motor output terminal (3).
49 CAS/SRM O Cassette mechanism/SRM mechanism Cassette mechanism: H.
voltage switching terminal. SRM mechanism: L.
50 N.C O Outputs Low. No connection.
51 N.C O Outputs Low. No connection.
52 ILL-ON O FL +B output terminal. ON: H, OFF: L
53 PAN-5V O Panel 5 V control terminal. Panel detected: H Panel not detected: L
54 N.C O Outputs Low. No connection.
55 BVdd - Positive power supply terminal.
56 BVss - Grounding terminal.
57 TYPE1 I Destination type switching port.
58 TYPE0 I Destination type switching port.
59 N.C O Outputs Low. No connection.
60 N.C O Outputs Low. No connection.
61 ST TYPE1 I IC2 destination type terminal. Default: L.
62 ST TYPE0 I IC2 destination type terminal. Default: L.
63 SRM-SW1 I Panel position detection switch 1.
64 D/A-SDA O D/A clock line. (V-LED) Panel detached: L.
Momentary power down: L.
65 L CE I/O CE terminal for LCD driver.
66 SRM-SW3 I Panel position detection switch 3.
67 SRM-SW2 I Panel position detection switch 2.
68 FWD/REV O TAPE EQ input switching terminal. FWD: L. REW: H.
During TAPE PLAY: H.
69 MS-CONT I/O
Constant switching terminal in case of blank detection.
During TAPE FF/REW or other than TAPE input: L.
Cassette mechanism detected: L.
Cassette mechanism not detected: H.
70 AVCONT O AD reference voltage control output. Same timing as P-ON. H during operation.
71 Avdd - Positive power supply terminal.
72 Avss - Grounding terminal.
73 Avref I Reference voltage supply terminal for A/D converter.
74 PHONE I PHONE detection terminal. TEL MUTE: No more than 1 V.
NAVI MUTE:2.5 V or more.
75 R-REEL I Cassette mechanism reel pulse input (REV). Vth = 2.5 V.
76 F-REEL I Cassette mechanism reel pulse input (FWD). Vth = 2.5 V.
77 N.C I No connection. Connected to GND.
78 SRM-DET I SRM mechanism detection. SRM mechanism detected: L.
79 NOISE I FM noise detection terminal. Model without RDS: Connected to GND.
80 S-METER I Signal meter detection terminal.
81 R-DATA I RDS decoder DATA input terminal. Model without RDS and
RBDS: Connected to GND.
82 R-QUAL I RDS decoder QUAL input terminal. Model without RDS and
RBDS: Connected to GND.
83 IFC-OUT I F/E IFC OUT input terminal. Station detected: L.
84 MUSIC I Music blank detection input. Music signal detected: L.
Music signal not detected: H.
85 PACK-DET I Cassette mechanism pack detection terminal. Cassette pack detected: L.
Cassette pack not detected: H.
86 DOLBY O Dolby ON/OFF switching. ON: H. OFF: L.
87 R-CLK I RDS decoder CLK input terminal. Model without RDS and
RBDS: Connected to GND.
88 CH-REQC I Request input from CH. ON: L.
89 KEY REQ I Communication request from LCD driver.
90 N.C I No connection. Connected to GND.
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KRC-794/Y
MICROCOMPUTER'S TERMINAL DESCRIPTION
6
Pin No. Name I/O Description Processing Operation
91 EQ-MUTE O EQ muting switching.
During TAPE PLAY: L. During TAPE FF/REW: H.
Other than TAPE input: H.
92 MTL O NORMAL/METAL switching. NORMAL: H. METAL: L.
93 BU-DET I Momentary power down detection terminal. Back-Up detected: L
Back-Up not detected (momentary power down): H.
94 CH-DATAC I DATA input terminal from CH.
95 CH-DATAH O DATA output terminal to CH.
96 CH-CLK I/O CLOCK input/output terminal from/to CH.
97 L-DATA L I DATA line from LCD driver.
98 L-DATA S I/O DATA line to LCD driver.
99 L-CLK I/O CLK line to LCD driver. Panel detected: L
100 N.C O Outputs Low. No connection.
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KRC-794/Y
TEST MODE
7
M&T-SRT Model Test Mode
1. How to enter the test mode
•While holding the FM and Preset 6 keys, reset the unit.
2. How to exit from the test mode
•While holding the Preset 6 key, reset the unit.
•(Note) The test mode cannot terminated by Acc OFF,
power OFF or momentary power down.
3. Initial status in the test mode
•Sources : All OFF.
•Display : All segments are lit.
•Volume : -10 dB (displayed as 30)
•Loudness : OFF
•CRSC : OFF regardless of the presence of switching
function.
•SYSTEM Q: Flat.
•Blank Skip : OFF. (C/R model)
•LED : White for no scanning. (VLCD model)
4. Special display in Tuner mode
•When any of the following messages is displayed in Tuner
mode, the front end may be abnormal.
•"TNE 2P NG": The EEPROM is set to the default (unsta-
ble values) because the F/E was shipped without passing
through the adjustment process, etc.
•"TNCON NG": Communication with the F/E is not possible.
5. Forced switching of K3I
•Each press of the Preset 6 key in Tuner mode should
switch K3I from AUTO →Forced Wide →Forced Middle
→Forced Narrow →AUTO. The initial status is AUTO
and the display shows these modes as follows.
•AUTO : FMA
•Forced Wide : FMW
•Forced Middle : FMM
•Forced Narrow : FMN
6. Test mode specifications of the CD receiver
•Forced ejection is inhibited in the reset start operation.
When the unit is reset while a CD is loaded in it, the CD
is not recognized by resetting.
•Each press of the Track Up key jumps to the following
track numbers.
No. 9 →No. 15 →No. 10 →No. 11 →No. 12 →No. 13 →
No. 14 →No. 9 (The cycle restarts from here.)
•Each press of the Track Down key jumps to the previous
track number to the track being played.
7. Audio-related specifications
•A short press of the Q key initiates the audio adjustment
mode.
•Pressing the ❉key on the remote initiates the audio
adjustment mode.
•Continuous holding of a remote control key is inhibited.
•Bass, Middle and Treble are adjusted in 3 steps of Min/
Center/Max with the Track Up/Down keys.
•Balance is adjusted in 3 steps of Left Max/Center/Right
Max with the Track Up/Down keys.
•Fader is adjusted in 3 steps of Rear Max/Center/Front
Max with the Track Up/Down keys.
•HPF is adjusted in 2 steps of Through/220 Hz with the
Track Up/Down keys.
•LPF is adjusted in 2 steps of Through/120 Hz with the
Track Up/Down keys.
•Bass f, Bass Q, Bass EXT, Middle f, Middle Q and Treble
f are not dealt with by the audio adjustment.
8. Menu-related specifications
•A short press of the CLK key initiates the Menu mode.
•Pressing the DNPP/SBF key on the remote initiates the
Menu mode.
•Continuous holding of a remote control key is inhibited.
•Calendar adjustment, calendar display switching and cal-
endar memo are eliminated from the targets of continuous
key holding. (FL model).
•In the color adjustment mode, pressing the Preset 1 key
sets Red, 2 sets Blue, 3 sets Green and 4 sets Green.
(VLCD model)
•Contrast is adjusted in 3 steps of 0/5/10 and the default
is 5. (VLCD/LCD model)
•Brightness is adjusted in 3 steps of 0/5/10 and the default
is 10. (Normal FL model)
9. Backup current measurement
•When the unit is reset while Acc is OFF (i.e. by turning
Back-Up ON), the MUTE terminal goes OFF in 2 seconds
in place of 15 second. (The panel, CD mechanism
and TAPE mechanism are not activated at this time.)
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KRC-794/Y
8
TEST MODE
10. Special display when the display is All ON
Pressing the Preset keys while the power is All OFF
displays the following information.
11. Other specifications
•Automatic panel closing when a tape/CD is inserted is
inhibited. (M&T model)
•Panel operation by turning power OFF/ON is inhibited.
(M&T model)
•Pressing the ATT key opens or closes the panel. (M&T
model)
•Messages such as "CODE OFF" are not displayed when
power is turned ON.
•Pressing the TI (AUTO) key during changer operation
turns 2zone ON. 2zone can be turned OFF by pressing
the TI (AUTO) key again. The P/S dot lights while 2 zone
is ON.
•Pressing and holding the CLK key for a second in the All
OFF status the Mask Key (security) write mode.
■Security-related information
• Forced Power ON mode (All models)
Even when the security (Mask key) is approved, resetting
the unit while holding the ATT and Preset 4 keys
makes it possible to turn the power ON for 30 minutes.
After 30 minutes have elapsed, it is not possible to return
to the previous condition unless the unit is reset again.
•Method of registration of the security code after
EEPROM (Tuner Unit Ass'y) replacement (Code
security model)
1. Enter the test mode. (See 1 How to enter the test mode)
2. Press the CLK key to enter the security registration
mode.
3. Enter the code using the Preset 1/2/3/4 keys.
Example: To enter "3510"
•Press the Preset 1 key 4 times.
•Press the Preset 2 key 6 times.
•Press the Preset 3 key twice.
•Press the Preset 4 key once.
4. Press and hold the DISP key for 3 seconds until
"APPROVED" is displayed.
5. Exit from the test mode. (See 2 How to exit from the
test mode)
(Note) All Clear is not applicable to the security code
of this model.
•Simplified method of clearing the security code
(K Type only)
1. While the code entry is requested, press and hold the
VOL UP key for 3 seconds while holding the DISP key
pressed.(This should turn ---- off.)
2. Enter "KCAR" from the remote. (Same way as the 00
model)
Press the 5 key on the remote twice, then press the
Track Up key. (This enters "K")
Press the 2 key on the remote 3 times, then press the
Track Up key. (This enters "C")
Press the 2 key on the remote once, then press the
Track Up key. (This enters "A")
Press the 7 key on the remote twice, then press the
Track Up key. (This enters "R")
3. The security code is cleared and the unit enters the All
OFF mode.
4. If you commit a mistake in the code entry, the unit
enters the code request mode again.
Version display
(8 digits, Month/Day/Hour/Minute)
(Display)
SYS xxxxxxxx System microcomputer
PAN xxxxxxxx Panel microcomputer
Serial No. display (8 digits)
(Note) CD/R K type eXcelon model
(Display) SNo. xxxxxxxx
Short press: View power ON time.
(The All OFF period is not counted.)
Long press/hold: Clear power ON time.
(Display)
PonTim xxxxx Max. 65535 (hours)
Short press: Display TAPE/CD/
MD operation time.
Long press/hold: Clear TAPE/CD/MD operation
time. (Display)
CDTime xxxxx (CD/R)
TapTim xxxxx (C/R) Max. 65535 (hours)
Short press: Display TAPE/CD/
MD ejection count.
Long press/hold: Clear TAPE/CD/MD ejection
count. (Display)
EjeTim xxxxx Max. 65535 (times)
Short press: Display Panel open/close count.
Long press/hold: Clear Panel open/close count.
(Display)
PnCnt xxxxx Max. 655350 (times)
PRESET1
PRESET2
PRESET3
PRESET4
PRESET5
PRESET6
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KRC-794/Y
9
TEST MODE
•Method of writing the Mask key while the EEPROM is
in the initial status
1. Enter the test mode. (See 1 How to enter the test mode)
2. Press the CLK key to enter the Mask key registration
mode. "TRANSMIT1" should be displayed now. The
display at this time should show "< >" in place of "[ ]".
3. Point the Mask key remote toward the light sensor,
and press and hold its key for more than 0.5 second.
4. When "TRANSMIT2" is displayed, press and hold the
key on the Mask key remote for more than 0.5 second
again. The first and second counter codes are not com-
pared at this time.
5. When "APPROVED" is displayed, the write operation
is complete. Now the demonstration mode is initiated
and the test mode is terminated.
(Note) In the same way as previous models, if 30 min-
utes have elapsed with no code written, an error occurs
and the power is turned OFF.
•Method of initializing the Mask key (How to reset the
unit from the Mask key approved condition to the
factory condition)
1. Enter the test mode. (See 1 How to enter the test mode)
2. "TRANSMIT1" is displayed and the Mask key entry
request mode is initiated.
The display at this time should show "❉❉" in place of "[ ]".
3. Press and hold the key on the Master key remote for
more than 3 seconds.
4. When "TRANSMIT2" is displayed, press and hold the
key on the Master key remote for more than 3 seconds.
5. When "APPROVED" is displayed, the Mask key is
cleared, the demonstration mode is initiated, the test
mode is terminated and the unit returns to the factory
condition.
•Method of clearing all Mask key-related data
1. Enter the test mode. (See 1 How to enter the test mode)
2. Press the CLK key to enter the Mask key registration
mode. "TRANSMIT1" should be displayed now.
3. Point the Master key remote toward the light sensor,
and press and hold its key for more than 3 seconds
(until the level display shows the full condition).
4. When "TRANSMIT2" is displayed, hold the key on the
Mask key remote for more than 3 seconds again.
If "TRANSMIT1" is displayed in place of "TRANSMIT2",
restart the procedure from step 3.
5. When "APPROVED" is displayed, all security data is
cleared and the unit returns to the condition before Mask
key writing with the EEPROM in the initial status.
w w w . x i a o y u 1 6 3 . c o m
Q Q
3
7
6 3
1 5 1 5
0 9 9
2
8 9
4 2
9 8
T E L 1 3 9 4 2 2 9 6 5 1 3 9 9 2 8 9 4 2 9 8 0 5 1 5 1 3 6 7 3
Q Q
TEL [phone] QQ 376315150 892498299 TEL [phone] QQ 376315150 892498299

10
ADJUSTMENT
ATTENTION
Set the controls and switches as follows.
BALANCE :center position BASS :center position LOUD :OFF DOLBY NR :OFF
FADER :center position TREBLE:center position
■Adjustment Points
•Adjusts Dolby Level
Reactivates TCC-130 (Dolby Level Tape), and adjusts VR1 so that the test pin output of Lch becomes -6dBm (387.5 mV).
Adjusts VR2 so that the test pin output of Rch also becomes -6dBm.
Assembly of FPC(Flexible PC board) onto Roller ass'y
Turn Roller ass'y by 2 times.
Hook the end of Roller ass'y to the tongue.
Insert the FPC into the slit of Roller ass'y then release the end of Roller ass'y and the tongue.
No
[1] AZIMUTH TCC-153
10kHz Connect an
AC voltmeter
to SP OUT TAPE PLAY
Head Azimuth
Screw Adjust the azimuth for each
Lch/Rch or FWD/RVS
becomes maximum
[2] PLAY BACK
LEVE TCC-130 Connect an
AC voltmeter
to CN2 TAPE PLAY VR1 (L)
VR2 (R)
(X87) 387.5mV (-6dBm)
CASSETTE DECK SECTION
ITEM INPUT SETTINGS OUTPUT
SETTINGS
TUNER
(RECEIVER)
SETTINGS
ALIGNMENT
POINTS ALIGN FOR FIG.
VR2
VR1
Lch
GND
Rch CN2
C MECHA
EQ PCB
(TEST
PIN)
tongue
Turn 2 times.
End of Roller ass'y
FPC
KRC-794/Y
w w w . x i a o y u 1 6 3 . c o m
Q Q
3
7
6 3
1 5 1 5
0 9 9
2
8 9
4 2
9 8
T E L 1 3 9 4 2 2 9 6 5 1 3 9 9 2 8 9 4 2 9 8 0 5 1 5 1 3 6 7 3
Q Q
TEL [phone] QQ 376315150 892498299 TEL [phone] QQ 376315150 892498299

11
Refer to the schematic diagram for the values of resistors and capacitors.
ABCDE
1
2
3
4
5
6
7
KI1
KI4
KS5
1
KI2
KS4
KS2
KI5
KS3
KS1
KI3
3
24
68
1
18
19
RST ATT 1 2 3 4 5 6 TI DISP
CLK
FMAM
SRC AUD
R23
R22
R24
R21
R18
R17
R20
R19
C6
C7 R13
R14
R12
R11
C1
C2
R15
R16
R2
R1
R3
R5 R4
R9
R10
R8
R6
R7
C3
C12
R29
R28
C14
C13
C9
C5 C4
R27
C11
CP1
CP2
CP3
KI3
KI5
KS1KS2
DGND
KS4
KI4
KI1
VDD
KS3 KI2
DIMMER
RESET
S.GND
L-CE
L-DATAS
L-DATAL
ILL+B
KS5
REMO
CLK L-
ILLUM G
EB
EB
BE
B
E
BE
BE
113 1
25
26
50 51 75 76
100
Q4
Q7 Q3
Q6
Q5
Q1
IC1
S28
D26
J1
X16-1540-12 (J74-1306-12) X16-1540-12 (J74-1306-12)
ED1
D24
D23
IC2
D10
D9
D12
D11
D6
D5
D8
D7
D13
D20
D22
D21
D18
D15
D14
D17
D16
D3
D1 D2
W5
13
C16
W2
C5 W4
W3
W6
W7
1
W8
VR1
C6 DOLBY
W9
DOLBY R
VR2 W1
1
24
5
C15
L
DOLBY L
R
13
CN4
(J74-1148-12)
S1
CN3 CN2
X87-3022-71
IC1 Q1
C4 W14
R4
C17
C24
31
30
R12
C26
C8
R14
C12 C14
R7
C22
W12
R6
20
21
R8
C23
R11
1011
1
40
C13
R10 C21
C20 R9
C7
R5
C25
C11
EB
R13
R1
C1
W11
R2
C2
R3
C3
PC BOARD
(COMPONENT SIDE VIEW) (FOIL SIDE VIEW)
Ref. No address
IC1 5C
IC2 2A
Q1 6C
Q3 3C
Q4 3C
Q5 3C
Q6 2C
Q7 3C
X16-1540-12
Ref. No address
IC1 7D
Q1 7D
X87-3022-71
KRC-794/Y
w w w . x i a o y u 1 6 3 . c o m
Q Q
3
7
6 3
1 5 1 5
0 9 9
2
8 9
4 2
9 8
T E L 1 3 9 4 2 2 9 6 5 1 3 9 9 2 8 9 4 2 9 8 0 5 1 5 1 3 6 7 3
Q Q
TEL [phone] QQ 376315150 892498299 TEL [phone] QQ 376315150 892498299

12
FGHIJ
1
2
3
4
5
6
7
W104
W107
CP7
R170
R171 C174
R136
C109
R134
R124
R107
R115
R194
C41
R97
R98
R104
R301
R73
R71
R101
R165
R166
R72
R113
R117
R357
R102
R76
R77
R78
R111
R75
C38
R312
C89
R344
R302
R303
R339
R327
R103
R328
R308
R99
R309
R325
C95
C96
R321
C93
R116
R323
R326
R324
R322
R305
R304
R310
R193
C308
R347
C224
R338
R358
R359
C191
R330
R335
R172
C256
CP10
CP2
CP3
CP4
CP1
R333
R12
R14
R13
R11
C88
R169
C135 R162
C136 C137
R161
C157
C156
C138
R219
R220
R131
R192
C131
R340
R195
X1
R114
R367
CP9
R196
CP8
C307
C305
R348
R286
R311
E
B
BE
BE
BE
BE
BE
BE
BE
BE
BE
BE
BE
BEBE
BE
BE
A8V
X2
ILL+B
20MHz
TEST
IC2D
IC2C SW5V
CLK
NOISE
IFC
PANEL5V
5V
SDA SCL
PMUTE
SVR
STBY
4.332MHz
NOISE
AUDIO
RESET
MCD/DATAS
SCD/DATAL
32KHz
C81
W7
W10
L6
L5
R110
R100
C94
C111
C84
L3
C133
C114
C90
C33
C32 C31
C34
W4
W9
W17
W16
W21W14
W18
W13
W15
W3
W8
W6
W20
C29
W1
C1
W2
C3
C2
W11
W12
W5
R123
C27
C30
C28
C169
W19
C112
R125
R108
L4
L7
X3
L12
C190
C226
C222
C85
C132
C82
C87
E
L1
C92
C154
L8
R118
C253
L9
C252
SMET
1
24
7
62
1
13
1
1
2
25
24
1
916
8
2
1576109348121113
B
BE
BE BE
BE EB
1
2
12 11
110
1213
12
1
28 15
14
1
25
26
50
51 75
76
100
1
89
16
E B E
BEE
IC2
Q73
IC11
D52
D21 Q3
Q1
Q4
Q46
Q39
Q86
Q87
Q24
Q25
Q34
Q32
Q85
IC1
D6
D3
Q2
D5
Q90
Q71
Q36
Q44
D16
D14
D12
Q26 Q28
P1
D37
D36
D33
D15
D17
D13
D18
D11
D39
D40
J3
D38
D43
CN2
Q42 Q38
D31
WH1
IC13
CN3
J1
J2
Q20
Q22
CN1
IC4
D41
CN4
D53
D42
D44
D46
D45
X14-6442-73 (J74-1397-02)
PC BOARD (COMPONENT SIDE VIEW)
Refer to the schematic diagram for the values of resistors and capacitors.
Ref. No address Ref. No address Ref. No address Ref. No address Ref. No address
IC1
IC2
IC4
IC11
IC13
4I
3H
3F
3J
5J
Q1
Q20
Q22
Q24
Q25
3G
6H
6H
5H
5H
Q28
Q32
Q34
Q36
Q38
5H
5G
6I
6I
5I
Q39
Q42
Q44
Q46
Q71
4H
6I
6I
4J
3G
Q73
Q85
Q86
Q87
Q90
2I
3I
2H
2H
2H
X14-6442-73
KRC-794/Y
w w w . x i a o y u 1 6 3 . c o m
Q Q
3
7
6 3
1 5 1 5
0 9 9
2
8 9
4 2
9 8
T E L 1 3 9 4 2 2 9 6 5 1 3 9 9 2 8 9 4 2 9 8 0 5 1 5 1 3 6 7 3
Q Q
TEL [phone] QQ 376315150 892498299 TEL [phone] QQ 376315150 892498299

13
Refer to the schematic diagram for the values of resistors and capacitors.
KLMNO
1
2
3
4
5
6
7
B E
BE
EB
EB
B
EB
E
BE
EB
BE
BE
B
BE
E
E
B
BE
BE
BE
W102
W101
R377
R126 R93
R92
R1
R2
R3
R87
R288
C99
C98
R190
R120
R121
R218
R217
R122
R106
R109
R94
R119
C83
C86
C91
W103
R345
R346
C251
R191
R361
C306
R373
R371
R365
R341
R366 R337
R336
R370
R375
R374
R372
R331
R81
C304
R332
C301
C302
C303
R287
R289
R80
R96
R95
R112
R307
R82
R364
R306
L10
R83
R135
C42
W105
R90
R89
R74
C108
C80
C39
R315
R352
C40
TH1
C36
C37
R10
C35
R24
R34
R167
R198
R376
C225
C221
C223
R221
C5
C6
R199
R313
C97
R168
C172
W106
C173
R47
R37 R8 R9
R7
R23 R33
C59
R38
R48
C60
GOI
1
7
148
43
12
D51
Q33
Q18 Q19
Q37
Q43
Q45
Q41
Q27
D32
Q31
Q30
Q29
D81
D82
IC15
IC10
Q21
D1
IC3
D22
Q23
D50
Q72
Q88 Q89
D2
X14-6442-73 (J74-1397-02)
PC BOARD (FOIL SIDE VIEW) KRC-794/Y
Ref. No address Ref. No address Ref. No address Ref. No address
IC3
IC10
IC15
Q18
Q19
5M
3M
4L
6M
6M
Q21
Q23
Q29
Q30
Q31
6M
4M
5L
5L
5L
Q33
Q37
Q41
Q43
Q45
6L
5L
5L
5L
5K
Q72
Q88
Q89
3M
2M
2M
X14-6442-73
w w w . x i a o y u 1 6 3 . c o m
Q Q
3
7
6 3
1 5 1 5
0 9 9
2
8 9
4 2
9 8
T E L 1 3 9 4 2 2 9 6 5 1 3 9 9 2 8 9 4 2 9 8 0 5 1 5 1 3 6 7 3
Q Q
TEL [phone] QQ 376315150 892498299 TEL [phone] QQ 376315150 892498299

ABCDE
1
2
3
4
5
6
7
IC1:
Q1 : DTC124EK or
(X87-3022-71)
J3CH CN
CXA2560Q
KRC103S
TAKEUP
REEL
2
SUB
CM2
MODE SW
SUPPLY
TAKE UP
FWD
REV
SUPPLY
REEL
MM
CM1
MAIN
PLAY
Lch
Rch
Rch
L
R
Lch
CN3
CN2
Q1
IN SW
S1
CN4
PACK
D22
EQ AMP
22K
22K
DPSS
PLAY
FF,REW
4.10V
4.06V
4.06V
4.06V
0V
4.06V
0V
4.03V
4.10V 4.04V
8.11V
4.06V
4.02V 4.12V
DOLBY
OFF
B,C :
: 0.4V 4.10V DPSS
PLAY
DOLBY
DOLBY4.04V B
C
OFF
4.06V
4.06V
4.02V
ON
1.23V
: 0V
: 4.73V
: 0V
: 4.43V
4.04V
4.06V
4.16V
0V
PLAY
FWD
REV
OFF,B :
C : 0.4V
DOLBY
: 0VON
: 2.9V
: 0V
0V
: 4.94V
ON : 4.77V
: 0VOFF
: 4.84V
MUTE
OFF
: 4.05V
METAL
: 0V
: 4.84V
: 0V
(X87-3022-71)
(X14-6442-73)
(E30-4942-05) : KRC-794/Y
DC CORD
IC1
TAPE MECHA (D40-1146)
1
4
3
2
REQ H
D GND
B.U.
CH CON
MUTE
A GND
RST
5713
8
RL+
7
RL-
351
RR-
FL+ FL-
FR- FR+
RR+
642
B
PNK/BLK
BLU/WHT
8
GND
642
A
BU
ORG/WHT
1
2YEL
EXT. CONT.
TEL MUTE
BRN
3
4
RED
BLK
BLU/WHT
ANT. CON
GRN/BLK
RR+5VIOL
VIOL/BLK RR-
RL-
6
7
RL+8GRN
WHT/BLK
GRY
FR+
GRY/BLK
FR-
FL-
WHT
FL+
9
10
11
12
16
13
14
15
ACC
+B
+B
AC
LINE OUT2
TAPE IN2
OUT REF2
PB OUT2
1932
K
A
K
C
R11C7
C13 0.1
0.033
+5V
E
C
NC12
7 MODE2
3+5V
E
9 F REEL
ANODE
R REEL
10
11
PON 5V8
21MOED16
MOT-G
MODE3
4
5
+8V
10K
VR1
4.7
R13
1K0.01
+
47u10
C6
C11
0.1
4700P
C17 0.47
C20
1 SUB+
SUB-
MOT+B
2
3
1
W11 R5C15 33u10
+180
R3 24K
C3 470P
1
2
3
4
C5
470P
R2
R1 24K
C1 470P
C2
+
24K
33u10
2
3
4
14MS OUT
PB REF
8LINE OUT1
TAPE IN1 OUT REF1 PB OUT1
40
2
1
PB FB1
PBTC1 VCC
5
4
3
7
6NC
PB GND
PB R IN1
39
PB F IN1
37
38
TCL1 TCH1
10
9
MSLPF
R8 220K R10 33K
R9 2.7K
C24
C23
0.47
13
12
11
G1FB
G2FB
MSTC
36
VCT
35
33 PB GND
PB F IN2
34
PB R IN2
17
16
15
14
NR MODE
MUTE SW
NR SW 15
17
16
18
TAPE SW
DR SW
18
19
5
R4
470P
5
C4
24K
33u50
C16
+
R6
180
0.01 1K
C14 0.1
23
PBTC2
PB FB2
31
29 30
DIREF
GND 26
27 28 24 25
0.1
C12
R7 20K
20
MS SW
TCL2
TCH2
MS
MODE
21 22
20
R12C8
VR2
10K
+8V
R14 10K
+B 8V4
3
R
GND
L
21
OUT R
A GND
OUT L1
2
3
DOLBY
MS OUT
B/C
DOLBY
ON/OFF
15 6
14 5
16 7
TAPE IN
F/R
MUTE
MTL
MS MODE
18
17 8
9
19
20
10
11
12
D GND13
28
27
100K
29 26 R80
R72 4.7K
R71 100
R73 4.7K R74 4.7K
DTA123JK
DTA124EK
DTC114YK
DTC124EK
DTC143TK
DTC143ZK
DTC144EK
KRC103S
UN5213
2SA1576A
2SB1218A
2SB709A
2SC2412K
2SB1277
2SB1443
2SA1037K
2SC4081
DTA114EUA
DTC144EUA
KRC104S
2SB1188
2SB1184
2SB1548 DAN202K
DAP202K
TC74HC02AF
M5237ML
TDA7479D
X14-6442-73 (1/4)
14
KRC-794/Y
w w w . x i a o y u 1 6 3 . c o m
Q Q
3
7
6 3
1 5 1 5
0 9 9
2
8 9
4 2
9 8
T E L 1 3 9 4 2 2 9 6 5 1 3 9 9 2 8 9 4 2 9 8 0 5 1 5 1 3 6 7 3
Q Q
TEL [phone] QQ 376315150 892498299 TEL [phone] QQ 376315150 892498299

FGHIJ
D33
SW5V
Q20
B.U.5V AVR
Q21
Q22
Q23
D38
D39
D40 Q28
CN4
Q31
P-CON SW
MUTE
Q29
Q30
D52
POWER IC
J1
J3 D31
D51
J2
D32
Q32
D43
Q39
AUDIO 8V AVR
DC IN
Q19
D45 D46
Q
J3 TOP VIEW
Q73
Q72
Q18
D53
Q34
Q44
Q33
D41
E-VOL. N.C.,MPX
MOTOR
DRIVER
DIMMER
SW
EXTERNAL
CONTROL
AMP ILLUMINATION
AVR
E-VOL
SW
MUTE
MOTOR
VOLTAG
DRIVE
SW
1
N4
D21
D3
D1
D18 D16
D12
D14
D11D13
D15
D17
D37 Q25
DETECTION
ACC.
Q24
D36
B. U
DETECTION
SUPPLY
MOTOR
DRIVER
Q38
D42
Q37
Q36
SW 14V
N
B
PRE OUT
DRIVER
MUTE
Q71
D50
47K
10K
22K
22K
47K
47K
2.2K
47K
4
22K
22K
22K
22K
22K
22K
22K
22K
7.5V
7.5V
14.4V 7.5V
7.5V 8.9V 1.37V 1.37V
7.5V 14.4V7.5V
0V-4.1V 7.5V
5.0V
0V
5V
0V
5V
0V
5V
5V
0V
0V
5V
0V
5V
0V
5V
13.7V
1.26V
13
2
0V
7.5V
7.5V
0V or 5.0V
13.5V
CAS:3.9V
SRM:7.5V
13.5V
0V
3.6V
4.15V
4.15V
4.15V
4.15V
4.15V
4.15V
0V
5V
4.15V
4.15V
0-4.5V
0-4.5V
3.0-4.9V
0.3-3.8V
5V
0V 0V
8.3V
4.15V
4.15V
4.15V
4.15V
0v
0V
0V
0V
5V 1.25V 1.45V
3.9V
3.9V
0.6V-
0.6V-
0.6V-
7.5V
3.9V
0V
5V
0V
0V
0V
0V
0V
IC3
IC10
IC4
73)
IC13
IC2
R109
22K
VIN VREF
R95
R96
C83 0.01
10u10
100u25
C85 100u6.3
+
C82
+
C84
22K
R93 100 R94
+
GND
4.3K
R89
220u10
C87
220
R92 15K R90 1 C86
24K
R87
2
1K
R108
1/2W
4.7K
3.3u25
C90
R104 4.7K
SUB +
1
11
Q28-31
1/2W
1
2
3
4
0.068
C92
+
0.1u50
R110 1K
+
C91 14
13 12
5 6
7
10 9 8
12
0.47u50
C111
+
FL
RL
3.9K
R136
FR
RR
TH1
13
FR+
RR+
FR-
RR-
C31
0.22u50
C33
0.22u50
+
22K
R13
22K
R11
22u16
C112
8
TAB GND RR- STBY RR+ VCC FR-
1
2
3 5 6
7 4
FRIN RRIN FR+ SVR GND
9
10
11
12
C34
0.22u50 0.22u50
1.5K
R134
C32 22K
R14
22K
R12
FL+ FLIN RLIN AUX IN RL+ GND RL- VCC GND
14
15 16
17
18 19 20
21
CD MUTE FL- GND
22
23
24
25
RR+
FR+
RR-
FR-
RL-
FL+
FL-
RL+
2
3
10
RL-
FL+
RL+
FL-
12
9
FR-
RR-
FR+
RR+
ACC
TEL MUTE
P-CON
EXT. AMP CONT
ANT
GND
DIMMER
67345
13 11121415
8
BUP
16
10u16
C30 R10
4
3300u16
+
RL+
RL-
FL-
FL+
1u50
+
C114
15
195
4
3
62
11
10
12
13
8
7
CH CON
MUTE
A GND
RST
Rch
REQC
DATA C
DATA H
Lch
CH CLK
1
2
3
4
5
6
7
8
9
10
11
12
13
REQ H
B.U
MUTE
Rch
A GND
REQ C
RST
DATA C
CH CLK
Lch
DATA H
D GND
CH CON
3
21
10
12
12
10 10K
R111
R112
100K
0.01
C93
R117
1K
560
R114
30 24
C94 1u50
+
+
R113
10K0.01
C95
VDD
VSS
22K
2.2K
C80
2200P
C81
R135
100
L12
SUB -
2
1GND
2OUT 2
4
3
IN 1 OUT 3
7
8 6 5
VCC 1 VREF IN 3 IN 2
10
9
OUT 1 VCC 2
1.2K
R120
2.2
R121
2.2
R122
0.22
C99
0.22
C98
1W1W
3
10
48
47
46
9
96
11 4
7
3
10 5
812
1
213
R34
3
2
1
CREF
VREF
27
O FL
NC
25
26
NC 28
4CAS L
CAS R
O FR
24
CD L
VDD
8NC
GND 21
CD R
5
7
6CD GND
O RL
O RR 22
23
S MUTE
MPX
12 LEVEL
QUAL 17
AFS
10
11 AM/IF
SDA
SCL 19
18
15
14 MP OUT
NC
MP IN
NC
920
16
13
+
C132
100u10
0.01
C131
4.7K
R171
1K
R170
0.1
C137
0.01
C157
150P
C136
4.7K
R161
10K
R169
4.7K
R162
0.1
C138
0.033
C156
0.47
C135
C5 1
2.2u50
+
C133
C6 1
7
6
5
13
14
FR
FL
RR
RL
RR
RL
FR
FL
4
3
13 10
3
W103
4
0.1
C109
10K
R312
47K
R131
31
R124
750
R126
2.2
52
IC13
0.01
C108
+8V
+8V
+B
+B
+B
+5V
+5V
+5V
+B
+B
+5V
+B
+B
+B
+5V
+5V
+5V
+B
+B
+B
+5V
+5V
+5V
+5V
+B
+B+B
+B
+B
+B
+B
+B
+B
R107
19
+B 8V
OUT R
A GND
OUT L
DOLBY
MS OUT
B/C
DOLBY
ON/OFF
TAPE IN
F/R
MUTE
MTL
MS MODE
D GND
47u6.3
27
100K 100K 100K
29 26
88
R80
R81
95
94
96
R82
4.7 +6
0.47u50
0.47u50
R72 4.7K
10
R3
R76 4.7K R75 4.7K R73 4.7K R74 4.7K
R77 47
47
R78
R2
R1
10
C3
+5
C2+7
C1
F1 10A
23
R103 R100
3.3K
C96
0.01
1/2W
18K
C89
0.01
R102
100K
R101
100K
C88
1000P
R99
5.6K
12K
R98
R97
12K
93
R116
100K 1.2K
R115
+B
11
+B
25
74
79
ILL +B
ILL +B
+5V
16
+B
+B
15
X14-6442-73 (2/4)
KRC-794/Y
w w w . x i a o y u 1 6 3 . c o m
Q Q
3
7
6 3
1 5 1 5
0 9 9
2
8 9
4 2
9 8
T E L 1 3 9 4 2 2 9 6 5 1 3 9 9 2 8 9 4 2 9 8 0 5 1 5 1 3 6 7 3
Q Q
TEL [phone] QQ 376315150 892498299 TEL [phone] QQ 376315150 892498299

KLMNO
CN4
Q41
Q42
Q2 Q1 Q3Q4
J2
Rch Lch Lch Rch
D6D5
GND GND
D44
D82
D45 D46
Q43
CN3
Q73
2
RST
SYSTEM u-COM
E-VOL
SW
MUTE
MOTOR
VOLTAGE
DRIVER'S
SW MAIN MOTOR
SUPPLY SW
MECHA
CASSETTE
D81
PRE
OUT
MUTE
PRE
MUTE
OUT
2
NOISE
BUFFER
PRE OUT
FRONT REAR
1
10K
47K
47K
10K
K
4.7K 4.7K 4.7K4.7K
4V
5.0V
0V
5V
0V
5V
0V
5V
0V
5V
0V
0V
0V
5V
5V
0V
0V
5V
0V or 3.25V
0V
5.0V
5V
0V
0V
5.0V
0V or 5.0V
0V
0V
5V
0V
0V
5V
0V
5.0V
5V
0V 0V
5V
5V
0V
5V
0V
0V
5V
5.0V
5V
0V
0V
0V
5V
0V
5V
5V
0V
4.4V
0V
5V
0V
0V or 5.0V
0V
5V 0V or 5.0V 0V
5V
0.6V or 1.6V or 4.0V
0V or 5.0V
0 or 5.0V
0V
5V
IC1
IC15
SUB +
1
FL 10u16
C29
+360
R9
R23 22KR24 22K
FR 10u16
C30
+360
R10
R37 22KR38 22K
R8
360
RR
C28
10u16
+360
RL 10u16
+
R7
C27
0.1
C60
0.1
C59
1K
R118
10K
R119
1/2W
25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3
51
52
53
54
55 56
57
58 59 60
61
62
63
64
65 66
67
68 69 70
71
72
73
74
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
SW 5V
DIMMER
ACC DET
NC
MUTE
ANT CONT
P CON
TEST
DIMMER CONT/DA-SDA
PRE MUTE
P MUTE
IC2 SCK
IC2 SDA
P STBY
P ON
BEEP
E VSS
E VDD
PLL CLK
PLL DATA
M
MC D
SC D
SC R
NC ILL ON PAN 5V NC VDD VSS TYPE 1 TYPE 0 NC NC ST TYPE 1 ST TYPE 0 SRM SW1 NC/DA-CLK MC REQ/L CE SRM SW3 SRM SW2 FWD/REV MSC AV CONT A VDD A VSS AVREF PHONE
CH MUTE
CH CON
CH REQH
CH RST
EXT AMP CONT
RESET
XT1
XT2
REGC
X2
X1
VSS
VDD
CLK OUT
NC
MOTOR
MODE 3
MODE 1
MODE 2
NC
SUB MOTOR 1
SUB MOTOR 2
SUB MOTOR 3
CAS/SRM
NC
CP4 1K
1K
R359
69 68
67
66
65
R328 100K R326 100K
100K R323 100K
100K
63
R324
53
CP3 1K
CP2 4.7K
X1 20MHz
X2
0.01
C251
27P
C302
C301
C303 1
29
30
26
27
28
42
46
47
48
44
43
R303 470
47K
R352
R302 470
R305 4.7K R304 4.7K
0.01
C307
R310 10K R311 10K R313 10K
R308 1K R309 1K 14
13
4 5
R301 1K
24
1GND 4
32 IN
OUT
NC
10K
R289
SUB -
23
+B
MOT
4
MOT
- G
5
3
MODE
6
MODE
1
5V
PON
2
MODE
R
REEL
ANODE
F
REEL
8711109
3
10
49
76 75
R190 120
41
A GND
OUT L
+B 8V
OUT R
2143
MTL
DOLBY B/C
DOLBY
MUTE
MS OUT
7658
F/R
MS MODE
11109
PACK IN
D GND
1312
ON/OFF
4 3
84
85 69 68
92
91
86
R198
47K
100K
R199
10u16
C190
+R193
100K
470
R194
0.01
C191
41
25
74
21
23
16 19
11
49
15
12
9
31
+
C252
47u6.3
4.7uH
L9
4.7K
R315
10K
R357
C306
R286
47K22K
52
180
R34
180
R33
180
R48
180
R47
+
C132
100u10
0.01
C131
4.7uH
L8
4.7K
R171
K
70
3
4
FR
FL
RR
RL
RR
RL
FR
FL
NC
12
REMO
NC
CP1 100K
R367
2.2K 10
R306
2.2M
R307
W104
C305 0.01
17
C308
1
22P
220
R287
10
C256
W107
0.01
+8V
+8V
+8V
+B +B
+B
+5V
+5V
+5V
+5V
+5V
+5V
+5V
+5V
+5V
+5V
+5V
+5V
+5V
+5V
R288
R321
43
42
44
CP10 4.7K
+8V
RST
79
ILL +B
+5V
+5V
X14-6442-73 (3/4)
16
KRC-794/Y
w w w . x i a o y u 1 6 3 . c o m
Q Q
3
7
6 3
1 5 1 5
0 9 9
2
8 9
4 2
9 8
T E L 1 3 9 4 2 2 9 6 5 1 3 9 9 2 8 9 4 2 9 8 0 5 1 5 1 3 6 7 3
Q Q
TEL [phone] QQ 376315150 892498299 TEL [phone] QQ 376315150 892498299

PQRST
1
2
3
4
5
6
7
WH1
ANT
CN1
A1
Q89
Q87
Q86
Q88
Q85
Q90
CN2
Q45
IC1 :
IC2 : TDA7407D
IC3 : M5237ML
IC4 : TA8263BH
IC10 : TC74HCO2AF
IC11 : TDA7479D
IC13 : BA6238A
IC15 : S-80837ANNP
D1 : RD6.8MW
D3,22 : MA3062-M
D5,6,50,51 : DAP202K or
D11,13-18,38-40,44 : AM01Z
D21 : MA3062WA
D31 : RM1OZLF
D32 : RB160L-40
D33,36 : MA4056(N)-M
D37 : MA4062(N)-M
D41 : 1SS133
D42 : MA4220-H
D43 : MA4056-M
D45 : MA4075-M
D46 : MA4036-H
D52,82 : DAN202K or
D81 : MA3047-M
Q18,72,86,87 : DTC124EK or
Q20,22 : 2SB1548(P)
: 2SC2412K or
Q31,41,43 : DTC114YK or
Q32,46 : DTC144EK or
Q39 : DTA123JK or
Q85 : DTC144EUA or
SIGNAL LINE
Q46
MA4110-L:D53
DTC143TK orQ1-4 :
Q21,24,34,37,73,90
2SA1037K or:Q23,29
2SB1277(Q,R)Q28 :
2SB1184Q33 :
Q36,44 UMC2N:
Q38,42 2SB1443:
2SA1576A orQ45 :
2SB1188(Q,R)Q88,89 :
J1
2/2
X16-
J1
D2 :
D2
D81
AM +B
SW
FM +B
SW
IFC OUT
BUFFER
UPD703033GC138
IMSA-6801
M1F60D12 :
COMPOSITE
OUT BUFFER
RDS
DECODER
PANEL
5V SW
B LINE
MA152WA
MA152WK
UN2216
KRC103S
2SD601A
2SB709A
KRC107S
KRC104S
KRA105S
2SB1218A
UN5213
(X14-6442-7X)
KRA103S
DTA124EK orQ19,30,71 :
SUB
M
22K
22K
22K
22K
47K
47K
47K
47K
0V
5V
0V
0V
5V
5.0V
2.5V
5V
5.0V 2.5V
0V
0V
0V
5V
0V
5.0V
0.6V
5V
0V
0V-4.8V
0V-4.0V
5V
0V 0V
5V
5V
0V
5V
0V
0V
5V
0V
5V
0V
5V
0V
5V
0.6V or 1.6V or 4.0V
5.0V
0V
5V
IC11
KRC-794/Y (1/2)
A
(X16-1180-10)
MASK MECHA
2
1
82
81
87
10u6.3
EXTRES GND
1
2
+
10u6.3
3
C224
4330P
C222
5
10P 14
RDDA
RDCK QUAL
16
OSC0 VREF
15 T57
13 OSC1 MPX
X3
VCC
OSEL
12
C223 10P
C221
6
7
8
C225 0.01
TSEL FILOUT
ARI
11
10 TM
9
+
5 4 3 2 1
100
99
98
97
96
95
94
93
92
91
90
89
88
87
86
85
84
83
82
81
80
79
78
77
76
70
71
72
73
74
75
PLL CLK
PLL DATA
AFC
FM+B
AM +B
NC
MC CLK/L CLK
MC DATA/L DATAS
SC DATA/L DATAL
CH CLK
CH DATA H
CH DATA C
BU DET
MTL
EQ MUTE
NC
SC REQ/KEY REQ
CH REQ C
R CLK
DOLBY
PACK DET
MUSIC
IFC OUT
R QUAL
R DATA
S METER
NOISE
SRM DET
NC
F REEL
AV CONT A VDD A VSS AVREF PHONE R REEL
CP9 4.7K
CP8 2.2K
R364
L10
100K
CP7 2.2K
R340 2.2K
R339 10K
R338 1K
2.2K
1K
C304
88
96
81
87
82
86
84
85
92
89
91
99
95
94
78
79
47K
R365 R366
47K
R303 470 R302 470
R304 4.7K
1
2
4 5
R301 1K
2
1
4
3
6
5
8
7
9
11
10
12
13
R376 470
R374 470
R373 470
R372 1K
R371 1K
R370 470
ILL GND
ILL +B
L CLK
L-CE
RESET
L-DATAS
L-DATAL
DIMMER
PAN RESET
REMO
NC
D GND
VDD
17
10
89
65
99
98
64
RDS OUT
AM IF OUT
S METER
AUDIO OUT
VDD 5V
NOISE OUT
DIG GND
SDA
SCL
IFC OUT
PLL + B
OSC GND
VT
FM ANT
OSC GND
OSC GND
W/N
OSC GND
AM + B
FM + B
AM ANT
RF GND
IF1 GND
IF1 + B
1K
R166
22K
R168
4.7uH
L3
R165
1K
22K
R167
4.7uH
L7
L6 4.7uH
4
5
10
13
47K
R172
1
2
4.7K
R220
1K
1
2
6
4
3
5
7
2.2K
R196
2.2K
R195
2.2K
R192
100K
R191
67
10
78
66
63
4.7K
R218 47K
R217
53
74
93
22K
R348
0.01
C173
R286
47K22K
470
R344 1M
R347
W102 98
R361 1K
R345
1K
R332
1K
R331
100u10
C154
+
L4
4.7uH
L5
4.7uH
W106
R221
10
C172
0.01
47
R83
100K
R375 1K
1K
R377
S.GND
S.GND
RESET
PAN RESET
VDD
D GND
N.C.
REMO
DIMMER
L-DATAL
L-DATAS
L-CE
L CLK
ILL GND
ILL +B
17
19
20
18
15
16
14
13
12
9
10
8
4
7
6
5
2
3
1
21
22
23
24
11
Q90
CONT
1000P
R333
R335
C226
+B
+8V
+8V
+8V +8V
+8V
+8V
+8V +8V
+5V
+5V
+5V
+5V
+5V
+5V
+5V
+5V
+5V
+5V
+5V
R288
376
NO
MODEL NAME
KRC-794/Y
UNIT
No.
2-73
R324
YES 1K
R367
R323,
3
R219
75
76
RST
52mH
L1
GND
1
3SRM DET
SUB -
4
2SW 2
5
7SUB +
6SW 3
SW 1
ILL +B
ILL +B
3
+5V
VDD
N.C.
D GND
REMO
PAN RESET
L-DATAL
DIMMER
L-DATAS
ILL GND
L-CE
L CLK
RESET
ILL +B
+8V
+8V+8V
+8V
3
1
2
4
7
5
6
1
2
3
4
5
6
8
7
9
10
11
12
13
5
4
3
2
1
13
12
11
10
9
8
6
7
CAUTION : For continued safety, replace safety critical components only with manufacturer's recommended parts (refer to parts list).
Indicates safety critical components. To reduce the risk of electric shock, leakage-current or resistance measurements shall be carried
out (exposed parts are acceptably insulated from the supply circuit) before the appliance is returned to the customer.
•DC voltages are as measured with a high impedance voltmeter. Values may vary slightly due to variations between individual
instruments or/and units.
!
KRC-794/Y
17
X14-6442-73 (4/4)
w w w . x i a o y u 1 6 3 . c o m
Q Q
3
7
6 3
1 5 1 5
0 9 9
2
8 9
4 2
9 8
T E L 1 3 9 4 2 2 9 6 5 1 3 9 9 2 8 9 4 2 9 8 0 5 1 5 1 3 6 7 3
Q Q
TEL [phone] QQ 376315150 892498299 TEL [phone] QQ 376315150 892498299

UVWXY
1
2
3
4
5
6
7
J1
1/2
118
J1
Q5
Q6
LCD DRIVER
REMOTE
SENSOR IC
Q1
S3 RST
REMO
SW
AVR
KEY SCAN
SW
D26
X16-
10.7V
0V
5.0V0V
0V
5V
5.0V
8.5V
6.8V
5.1V
3.4V
1.7V
0V
5.0V
0V 5.0V
0V
0V
10K
10K
10K
10K
A
IC1
IC2
(X16-1540-12)
ED1
2
3
4
5
6
7
8
9
10
11
12
13
ILL+B
ILLUM G
L CLK
L CE
RESET
L DATAS
L DATAL
DIMMER
NC
REMO
NC
D GND
1K
1K
CP2
KI1
KI4
KI3
KI2
4.7
R11
75 74 73 72 71 70 69 68 67 66 65 64 63 62 61 60 59
1
2
3
4
5 6
7
8 9
10
11
12
13
14
15 16
17
18
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
KS5
KS4
KS3
KS2
KS1
COM1
COM2
COM3
COM4
COM5 COM6
COM7
COM8 COM9
COM10
S60 S
S1 S2 S3 S4 S5 S6 S7 S8 S9 S10 S11 S12 S13 S14 S15 S16 S17 S
KI5
REMO
RED
GREEN
KEY
VDD
VLCD
VLCD0
VLCD1
VLCD2
VLCD3
VLCD4
VSS
TEST
OSC
INH
DO
CE
CL
DI
S4
S3
S2
S1
S10
S8
S7
S6 S5 S9
S15
S14
S13
S12
S11
S
S17
S16 S60
S
C4
C1
C8
C2
C3
C7
C5 C6
KS1
KS4
KS2
KS3
CP3
1K
R5
C4 0.1
C3 0.1
R4
C2 0.1
R3
C5
100
R9
2.2
C7
79 KI3
78 KI2
KI4
80
KI1
77 KS6
76
KI5 R13
1K
84
83
1
VDD
S.GND
R10
CP1
470
R8 22K
97
98
99
100
97
98
99
100
C1 680P
R1 43K
GND2
VCC
4
3
GND1
OUT
1
2
KS5
R14 1K
DI
3.9K
R6
2.2K2.2K2.2K
R2
2.2K
C6
22K
750
SEG17 35
S1
SEG1 19
27
SSEG9
SEG5 SEG3
SEG4
SEG2 21
20 22 23
SEG8
SEG7
SEG6 24
25 26
S5 S3
S2
S4
S6 S8
S7
31SEG13
SEG12
SEG11
SEG10 29
28 30
SEG14
SEG15 SEG16 33
32 34
S9
S10
S11
S12
S14
S13 S15 S16
COM1
S60 S56
S57
S59 S58
S54
S55
COM3 COM2 COM4 COM5 COM6 COM7 COM8 SEG60 SEG58 SEG59 SEG57 SEG56 SEG54 SEG55
S32
43SEG25 39SEG21
SEG20 SEG19 SEG18 37
36 38
SEG22
SEG23
SEG24 41
40 42
S17
S18 S20 S19
S21
S22
S23
S24
SEG26
SEG27
SEG28 45
44 46
SEG32
SEG31
SEG30 SEG29 47
48 50 49
S28 S26 S25
S27
S30 S29
S31
S40
SEG36 SEG35 SEG33
SEG34 51
52 53 54
SEG38 SEG39 SEG40
SEG37 56
55 57 58
S36
S34
S33 S35 S38
S37
S39
SEG42
SEG43
SEG44
SEG41 59
60 62 61
SEG47
SEG46 SEG45 63
64 65
S44
S42
S41
S43 S46 S45
S
5 9
10
7
8 6
4
17
18 15 16 13
14
12
11
S.GND
Q6
+10.7V
+5V
+5V
+5V
+5V
R12
0.1
2.2
Q5
R7
C3
C1
C2
C6
C7
C5
C4
C8
+10.7V
+B
+B
CAUTION : For continued safety, replace safety critical components only with manufacturer's
recommended parts (refer to parts list).
Indicates safety critical components. To reduce the risk of electric shock, leakage-current or
resistance measurements shall be carried out (exposed parts are acceptably insulated from the
supply circuit) before the appliance is returned to the customer.
•DC voltages are as measured with a high impedance voltmeter. Values may vary slightly due to
variations between individual instruments or/and units.
!
KRC-794/Y
X16-1540-12 (1/2)
18
w w w . x i a o y u 1 6 3 . c o m
Q Q
3
7
6 3
1 5 1 5
0 9 9
2
8 9
4 2
9 8
T E L 1 3 9 4 2 2 9 6 5 1 3 9 9 2 8 9 4 2 9 8 0 5 1 5 1 3 6 7 3
Q Q
TEL [phone] QQ 376315150 892498299 TEL [phone] QQ 376315150 892498299

ZAA AB AC AD
1
2
3
4
5
6
7
D7 D6 D5
D10 D9 D8
D18 D15 D14
D22 D16
D21 D20 D17
D13 D12 D11
D23
S1
VOL-
S2
S4 ATT S5
S9
4
S11
6S12
S8
S10
TI
5
2
S7
1
S6 SRC S22
S26
AM
FM
EJECT
S15
S17S16
S18
S14
S24
S20
AUD
S25
S13
DISP
Q3
IC1 : LC75808W
IC2 : RS-171
Q1,6 : DTA114EUA or
Q3-5 : 2SC4081
D2
DIMMER SW
Q4
B30-1571-05
MA3082-M
D1,2 :
D26 :
R
Q7
VOL+
3
S21
CLK
S27
S19
S23
DTC143ZKQ7 :
B30-1605-05D5-22 : B30-1564-05D23,24 :
OPEN
S28
D1
D24
B LINE
GND LINE
KRA302
RED LED SW
GREEN
LED SW
47K
4.7K
KRC-794/Y (2/2)
330
R17
510
R22
R23
270
C13 0.01
KS3 KS5
KS2
KS1
KI1
KI2
KI3
KI4
10K
R15
KI5
62 61 60 59 58 57 56 55 54 53 52 51
50
49
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
27
26
15 16
17
18 19 20
21
22
23
24
25
COM9
COM10
S60 S59 S58
S57
S56 S55
S54
S53
S52
S51
S45
S44
S43
S42
S41
S40
S39
S38
S37
S36
S35
S34
S33
S32
S31
S30
S29
S28
S27
S26
S15 S16 S17 S18 S19 S20 S21 S22 S23 S24 S25
S15 S20 S19 S18
S17
S16
S21
S22
S23
S38
S34
S32
S31
S33
S36
S35
S37
S46
S42
S40
S39
S41
S44
S43
S45
S47
S50
S30
S29
S60 S59 S58
S57
S56 S55
S54
S53
S52
S51
C11 0.01
10K
R16
S49
S48
S25
S24
S50
S46
S47
S48
S49
28
29
30
31
32
S28
S27
S26
R18
330
R19
330
R20
330
R21
330
84
83
330
R24
KS4
DI
SEG52
S56
S57
S53
S54
S55
SEG56 SEG54 SEG55 SEG53
S51
S52 SEG51
SEG44 62
SEG48
SEG47
SEG46 SEG45 63
64 65 66
S44
S46 S45
S47
SEG50 SEG49 68
67 S49
S48 S50
5 6 3
4
2
1
10K
R28 10K
R27
C12 0.01
C14
+B
0.01
+10.7V
+10.7V
+10.7V
+10.7V
KRC-794/Y
19
X16-1540-12 (2/2)
w w w . x i a o y u 1 6 3 . c o m
Q Q
3
7
6 3
1 5 1 5
0 9 9
2
8 9
4 2
9 8
T E L 1 3 9 4 2 2 9 6 5 1 3 9 9 2 8 9 4 2 9 8 0 5 1 5 1 3 6 7 3
Q Q
TEL [phone] QQ 376315150 892498299 TEL [phone] QQ 376315150 892498299

20
KRC-794/Y
EXPLODED VIEW (MECHANISM)
Parts with the exploded numbers larger than 700 are not supplied.
AB
1
2
3
58
56
57
52
53
54
CM1
CM2
25 21 24
45
23
65
65
66
66
67
67
10
11
1
31
30
34
33
9
9
HD1
17 15
4
22
12
12 20
5
67
26
48
48
49
27
94
91
92
94
D
N
G
H
CC
F
B
EE
E
B
G
893
H
N
D
876
Ax2
Ax2 K
J
J
44
w w w . x i a o y u 1 6 3 . c o m
Q Q
3
7
6 3
1 5 1 5
0 9 9
2
8 9
4 2
9 8
T E L 1 3 9 4 2 2 9 6 5 1 3 9 9 2 8 9 4 2 9 8 0 5 1 5 1 3 6 7 3
Q Q
TEL [phone] QQ 376315150 892498299 TEL [phone] QQ 376315150 892498299