EJECT
B NR
KRC-688
PWR
OFF
LOUD
MENU
DISP
NAME.S
SCAN
B.S/RDM
REP
D.SCN
MTL/M.RDM
DISC
DISC
DAB
AUD
45W 4
X
AUTO
AME
PROG
EJECT
AUTO
AME
DISP
NAME.S
KRC-508S
PWR
OFF
LOUD
MENU
SCAN
B NR
B.S/RDM
REP
D.SCN
MTL/M.RDM
DISC
DISC
DAB
AUD
45W 4
X
PROG
KRC-508S
KRC-688
CASSETTE RECEIVER
SERVICE MANUAL
C
2000-3 PRINTED IN KOREA
B51-7599-00 ( K ) 1785
Front glass assy
(B10-3209-08)
Escutcheon assy
(B07-2195-08)
Panel assy
(A64-2088-08)
Lever
(D10-4514-08)
Mounting hardware assy
(J21-9585-08)
DC cord assy
(E30-4864-08)
Plastic cabinet assy
(A02-1494-08)
The CASSETTE MECHANISM OPERATION DESCRIPTION is the same model D40-1122-05.
Please refer to the service manual for model D40-1122-05(B51-7452-00).
Stay
(J54-0611-08)
Escutcheon
(B07-2186-08)
Screw set
(N99-1689-08)
Screw set
(N99-1688-08)
KRC-688
KRC-508S
Panel assy
(A64-2088-08)
Front glass assy
(B10-3208-08)
Escutcheon assy
(B07-2195-08)
Remote controller assy
(A70-0883-05)
: KRC-688 only
Size AAA battary
(Not supplied)
: KRC-688 only
40%
KRC-508S/688
2
BLOCK
DIAGRAM
TUNER
ANT
SGS-IC
E PROM
E-VOL
TDA7400D
NOISE AMP
POWER IC
TDA7386
EQ-AMP
UPD784217AGF503
u-COM
CD-CH
RST
LCD-Dr
LC75883E
REMO
KEY MATRIX
LCD
BU 5V
SW 5V
PNL 5V
AUDIO 8V
SW 14V
MOTOR 14V
ILL 11V
BU 14V
TDA7479D
RDS DETECTOR
SERVO 14V
CXA2560Q
MS. B/NR
CXA2559Q
MS
MOTOR-Dr
BA6219BFP-Y
(D40-1141-08)
CASSETTE MECHA
TU100
IC200
IC300
IC150
IC1
IC250
IC500
Q610
Q621
Q616
Q612
Q618
Q622
Q5
Q1
IC900
REAR
FRONT
REAR
FRONT
BU 5V
SW 5V
PNL 5V
SERVO 14V
MOTOR 14V
ILL 11V
FM
AM
CASS
CD-CH
FRONT
10K
10K
REAR
2
FRONT
REAR
AIDIO 8V
KRC-680R/578R/RY
USED
KRC-680R/578R/RY/508S/688
KRC-680R
KRC-508S
KRC-578R/RY
KRC-688
E: KRC-578R/RY
KRC-508S
K:
KRC-680R/688
M:
CASS
AM(E)
AM(K,M)
FM(E)
FM(K,M)
CD-CH
310mV
(E)
(K,M)
(E)
(K,M)
1200mV
FM(K,M)
CASS
AM
FM(E)
CD-CH
FM(K,M)
CASS
FM(E)
AM(K,M)
AM(E)
CD-CH
FRONT
REAR
CD-CH
CASS
AM(E)
AM(K,M)
FM(E)
FM(K,M)
: 730mV
: 560mV
: 1280mV
: 1660mV
: 2900mV
: 1490mV
: 400Hz 40KHz Dev
: 400Hz 75KHz Dev
: 1KHz 0dB
: 400Hz 30% Mod
: 1KHz 0dB
: 1370mV
: 670mV
: 1180mV
: 2650mV
: 2650mV
: 510mV
: 1530mV
: 1370mV
: 1180mV
: 670mV
: 1530mV
: 510mV
: 170mV
: 350mV
: 150mV
: 140mV
: 2900mV
: 1660mV
: 1280mV
: 560mV
: 1490mV
: 730mV
AM(K,M)
CASS
AM(E)
CD-CH
FM(E)
FM(K,M)
KRC-508S/688
3
MICROCOMPUTER'S TERMINAL DESCRIPTION
Pin
Pin Name
Signal Name I/O
Purpose
Operation Description
1
P60/A16
ST_TYPE1
I
E-VOL setting selection input
DEFAULT:LO
2
P61/A17
ST_TYPE2
I
E-VOL setting selection input
DEFAULT:LO
3
P62/A18
JS_TYPE1
I
Genuine/generally-marketed identification
DEFAULT:LO
input.
4
P63/A19
TYPE1
I
Destination type switching input 1
5
P64/RD
TYPE2
I
Destination type switching input 2
6
P65/WR
TYPE3
I
Destination type switching input 3
7
P66/WAIT
NC
O Not used
8
P67/ASTB
NC
O Not used
9
Vdd
-
Positive power supply pin
10
P100/TI5/TO5
AMP_SVR
O Power IC reset control
Power ON: Lo.
11
P101/TI6/TO6
AMP_STBY
O Power IC standby control
Standby canceled: Hi.
Standby mode: Lo.
12
P102/TI7/TO7
AMP_MUTE
O Power IC muting control
Muting ON: Lo. Muting OFF: Hi.
13
P103/TI8/TO8
NC
O Not used
14
P30/TO0
ACC_DET
I
Acc detection input
ACC OFF:HI ACC ON:LO
15
P31/TO1
BU_DET
I
B-U detection input
B-U down: Hi. B-U normal: Lo.
16
P32/TO2
SMALL
I
Small input
Dimmer ON: Lo. Dimmer OFF: Hi.
17
P33/TI1
P_CONT
O Power control
ON:HI OFF:LO
18
P34/TI2
P_ANT
O Power antenna control
TUNER: Hi. Other sources: Lo.
19
P35/TI00
REMO
I
Remote control input
20
P36/TI01
P_ON
O Internal power control
ON:HI OFF:LO
21
P37
ILL_ON
O LED lighting control output
Lighting ON: Hi. Lighting OFF: Lo.
22
TEST
-
IC test pin
23
P90
IC2_SDA
I/O E-VOL/E's + data input/output
24
P91
IC2_SCK
O E-VOL/E' + clock output
25
P92
MUTE
O Muting control
Muting ON: Hi. Muting OFF: Lo.
26
P93
SW5V
O SW 5 V control
ON:LO OFF:HI
27
P94
F/E_DATA
I/O IC3 data input/output
28
P95
F/E CLK
O IC 3 clock output
29
P120/RTP0
CH_CON
O CH control
ON:HI
30
P121/RTP1
CH_REQH
O CH send request output
Requested: Lo.
31
P122/RTP2
NC
O Not used
32
P123/RTP3
NC
O Not used
33
P124/RTP4
C-MAIN_M
O C-mechanism main motor control
ON:HI OFF:LO
34
P125/RTP5
C-SUB_M+
O C-mechanism loading motor control
35
P126/RTP6
C-SUB_M-
O C-mechanism loading motor control
36
P127/RTP7
NC
O Not used
37
Vdd
-
Positive power supply pin
38
X2
-
Main system clock oscillator pin
39
X1
-
Main system clock oscillator pin
40
Vss
-
GND pin
41
XT2
-
Sub-system clock oscillator pin
42
XT1
-
Sub-system clock oscillator pin
43
RESET
I
System reset input pin
44
P00/INTP0
NC
O Not used
45
P01/INTP1
RDS_CLK
I
RDS clock input
46
P02/INTP2/NMI
CH_REQC
I
CD-CH send request input
Requested: Lo.
47
P03/INTP3
LCD_DATAL
I
Data input from LCD driver
48
P04/INTP4
C-MODE_1
I
C-mechanism mode detection 1 input
49
P05/INTP5
C-MODE_2
I
C-mechanism mode detection 1 input
50
P06/INTP6
C-MODE_3
I
C-mechanism mode detection 1 input
784217AGF503(504)(IC1 : MAIN UNIT)
KRC-508S/688
4
MICROCOMPUTER'S TERMINAL DESCRIPTION
Pin
Pin Name
Signal Name I/O
Purpose
Operation Description
51
AVdd
-
A/D analog power pin
52
AVref0
-
A/D reference voltage input pin
53
P10/ANI0
PHONE
I
PHONE detection input
<1 V: PHONE. >
2.5 V: Navigation muting.
54
P11/ANI1
NC
I
Not used
55
P12/ANI2
NOISE
I
FM noise detection input
56
P13/ANI3
S-METER
I
FM S-meter input
57
P14/ANI4
NC
I
Not used
58
P15/ANI5
NC
I
Not used
59
P16/ANI6
REEL_S
I
C-mechanism supply reel detection
60
P17/ANI7
REEL_T
I
C-mechanism take-up reel detection
61
AVss
-
A/D and D/A GND pin
62
P130/ANO0
NC
O Not used
63
P131/ANO1
NC
O Not used
64
AVref1
-
D/A reference voltage input pin
65
P70/RxD2/SI2
CH_DATAC
I
Data input from CD-CH
66
P71/TxD2/SO2
CH-DATAH
O Data output to CD-CH
67
P72/ASCK2/SCK2 CH_CLK
I/O CD-CH clock input/output
68
P20/RxD1/SI1
LCD_DATAL
I
Data input to LCD driver
69
P21/TxD1/SO1
LCD_DATAS
O Data output from LCD driver
70
P22/ASCK1/SCK1 LCD_CLK
O Clock output to LCD driver
71
P23/PCL
NC
O Not used
72
P24/BUZ
BEEP
O Beep output
73
P25/SI0
NC
O Not used
74
P26/SO0
PNL_DET1
I
Panel detection
75
P27/SCK0
NC
O Not used
76
P80/A0
LCD_INH
O Reset output to LCD driver
77
P81/A1
LCD_CE
O CE output to LCD driver
78
P82/A2
SRT_SW1
I
SRT position detection input
79
P83/A3
SRT_SW2
I
SRT position detection input
80
P84/A4
NC
O Not used
81
P85/A5
NC
O Not used
82
P86/A6
NC
O Not used
83
P87/A7
C-MSC
O EQ amp FF/PLAY control
PLAY:HI OFF:LO
84
P40/AD0
C-F/R
O Tape transport direction switching
FWD:LO REV:HI
85
P41/AD1
C-MUTE
O Tape muting control
MUTE:HI
86
P42/AD2
C-MS_IN
I
Inter-music pulse detection
87
P43/AD3
C-MTL
O MTL ON/OFF control
ON:HI OFF:LO
88
P44/AD4
C-NR
O Dolby ON/OFF control
ON:HI OFF:LO
89
P45/AD5
NC
O Not used
90
P46/AD6
NC
O Not used
91
P47/AD7
RDS_DATA
I
Data input from RDS decoder
92
P50/A8
RDS_QUAL
I
Quality input from RDS decoder
93
P51/A9
AFC
O PLL high-speed lock-up pin
During reception: Hi.
During search: Lo.
94
P52/A10
FM/AM_SD
I
FM/AM SD input
Station detected: Hi.
95
P53/A11
IF_COUNT
I
Not used
96
P54/A12
NC
O Not used
97
P55/A13
AM+B
O AM power control
ON:HI
98
P56/A14
FM+B
O FM power control
ON:HI
99
P57/A15
NC
O Not used
100
Vss
-
GND pin
784217AGF503(504)(IC1 : MAIN UNIT)
5
KRC-508S/688
TEST MODE
(1) How to enter the test mode
While holding the FM and Preset 6 keys simultaneously,
reset the unit.
All indicators and display segments are ON at the start of
test mode.
(2) How to exit from the test mode
Reset the unit.
(Note) The test mode cannot be canceled by turning Acc
OFF, power OFF or momentary power down.
(3) (return to beginning)
Pressing the Track Down key jumps to the previous track
to the track being played.
(4) Test mode specification of the tape
o The Blank Skip is initially OFF.
(5) Audio
o The volume is -10 dB (displayed as 30).
o LOUD is OFF, and CRSC is also OFF whether the
function is provided or not.
o With the Bass/Treble and Balance/Fader controls,
pressing the Up/Down key switch the setting alternate-
ly to: Full Boost => Full Cut => Full Boost, Full Right ->
Full Left => Full Right, or Full Front ~> Full Rear =>
Full Front.
o With the high-pass filter, pressing the Up key sets it to
Through/100 Hz/200 Hz and pressing the Down key
sets it to 200 Hz/100 Hz/Through.
o Other adjustments function in the same way as normal
mode.
(6) Backup current measurement
When the unit is reset (backup turned on) while Acc is
OFF or when Acc is turned OFF in test mode, the MUTE
terminal goes on in 2 seconds, instead of 1.5 second.
(The panel, CD, C and MD mechanisms are not activated
at this time.)
(7) Security code registration after E2PROM replacement
servicing (E/M type only)
1. Enter the test mode. (See (1) How to enter the test
mode.)
2. Press the SRC key to set All OFF.
3. Press and hold the AUDIO key for 1 second to enter
menu mode.
4. Press the FM/AM key to select "SECURITY".
5. Press and hold the Track Up/Down for 2 seconds.
6. Enter the code by pressing the Preset 1, 2, 3 and 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 2 times.
- Press the Preset 4 key once.
7. Press and hold the DISPLAY key for 3 seconds to dis-
play "APPROVED".
8. Quit the test mode (See (2) How to exit from the test
mode.)
(8) How to clear the simple security code (K type only)
1. While the code is requested, press and hold the DISP
key and press and hold the VOL Up key for 3 seconds.
("----" disappears.)
2. Enter "KCAR" from the remote control unit. (Same
operation as the '98 model)
- Press numeric key 5 twice then press the Track Up
key. (This enters "K".)
- Press numeric key 2 three times then press the
Track Up key. (This enters "A".)
- Press numeric key 2 once then press the Track Up
key. (This enters "A".)
- Press numeric key 7 twice then press the Track Up
key. (This enters "R".)
3. The security is canceled and the unit enters the
TUNER mode.
(9) Other
o The DNPP/SBF key of the remote control unit (RC-510)
functions as the menu mode ON/OFF key.
o The OPEN/CLOSE key of the remote control unit (RC-
510) functions as the audio adjustment mode ON/OFF
key.
o The menu is displayed by displaying only the required
features.
o Message such as "CODE OFF" is not displayed when
power is turned ON.
o The contrast can be adjusted only to 0/5/10 using the
Up/Down keys.