NAD C 426 User manual
NAD
C 426
STEREO
AM/FM TUNER
C 426
STEREO
AM/FM TUNER
SERVICE MANUAL
- 2 -
SERVICE SAFETY PRECAUTIONS
1. Safety check out
(Only U.S.A. model)
Before returning the product to the customer, make leakage current or resistance measurements
to determine that exposed parts are acceptably insulated from the supply circuit.
Parts marked with the symbol are critical with regard to the risk of fire and electric shock.
Replace only with parts recommended by the manufacturer.
CONTENTS
DESCRIPTION . .......................................................... PAGE
SPECIFICATIONS............................................................3-4
REAR PANEL / FRONT PANEL . ................................................. 5
DISASSEMBLY INSTRUCTIONS ................................................. 6
BLOCK DIAGRAM . ........................................................... 7
WIRING DIAGRAM ............................................................ 8
ADJUSTMENT POINTS DIAGRAM . .............................................. 9
INSTRUMENT SETUP . ....................................................... 10
ALIGNMENT PROCEDURES ....................................................11
PCB LAYOUT . ............................................................12-14
SCHEMATIC DIAGRAM . ....................................................15-17
IC BLOCK DIAGRAM . ......................................................18-22
ELECTRICAL PARTS LIST ...................................................23-31
EXPLODED VIEW............................................................ 32
EXPLODED VIEW PARTS LIST ................................................. 33
PACKING DIAGRAM.......................................................... 34
- 3 -
SPECIFICATIONS
AM BAND SPECIFICATION
Frequency Range CA 530 - 1710 KHz Step 10 KHz
EU 531 - 1602 KHz Step 9 KHz
FREQ (KHz) UNIT LIMIT
1. Usable sensitivity 999 dBuV <= 30
(400Hz, -20dB, direct input) /1000
2. S/N RATIO 999 dB >= 38
(5mV input) /1000
3. THD (5mV input) 999 % <= 3
/1000
4. IF Rejection (450KHz) 603 dB >= 36
(ref. to item 8) /600
5. Image Rejection (F+2xIF) 1404 dB >= 25
(ref. to item 8) /1400
6. Selectivity 999 dB >= 17
(ref. to item 8) /1000
7. Output 999 mV 100 ~ 180
(30%, 10mV) /1000
8. Loop sensitivity 20dB S/N 999/1000 dB <= 68
603 / 600 dB <= 68
1404 / 1400 dB <= 68
9. Frequency response 100 - 2.3KHz 999 /1000 dB 0 +/- 6dB
(400 Hz, 5mV)
FM BAND SPECIFICATION
Frequency Range CA/EU 87.5 - 108MHz Step 50 KHz
FREQ UNIT LIMIT
1. Usable sensitivity MONO 98MHz dBu <= 15
IHF (3% THD)
2. S/N RATIO
(60dBu A filter) MONO 98MHz dB >= 72
(60dBu A filter) STEREO 98MHz dB >= 68
3. THD (60dBu Audio LPF) MONO 98MHz % < 0.4
(60dBu Audio LPF) STEREO 98MHz % < 0.6
L = R, C=40KHz Dev.
4. IF Rejection (10.7MHz) CA&EU 98MHz dB > 80
(refer to item 1)
5. Image Rejection (119.4 MHz) CA&EU 98MHz dB >= 70
(refer to item 1)
- 4 -
6. Capture ratio (40dBu) dB < 3
7. AM Supression 98MHz dB > 60
@ 60dBu 100% mod FM, 30% mod AM
8. Pilot suppression L & R 98 MHz dB > 60
9. Frequency response 20Hz & 10KHz dB 0 +/- 1.5
( 1KHz Ref ) UL 75Us,CE50Us
10. Channel Separation @ 30 Hz dB >= 28
(60dBu IHF wtd) 1 KHz dB >= 38
10KHz dB >= 28
11. Alternate channel selectivity +/-400KHz, IHF UL dB >= 35
CE dB > 60
12. Muting level dBu 18 +/-6.
13. Output CA 98MHz mV 350~600
EU 550~900
14. RDS decode sensitivity. dBu <= 30
15. Auto-search sensitivity ON dBu <= 30
OFF dBu >= 15
16. Blend ON separation@1KHz 98MHz dB 6 +/-2
- 5 -
REAR PANEL / FRONT PANEL
1. FM ANTENNA TERMINAL
2. AM ANTENNA TERMINAL
3. OUTPUT (L, R)
4. RS-232
5. IR IN
6. +12V TRIGGER IN
7. AC MAINS INPUT
1. STANDBY LED
2. STANDBY BUTTON
3. FM/AM
4. FM MUTE/MODE
5. BLEND
6. DISPLAY
7. MEMORY
8. PRESET/TUNE
9. REMOTE SENSOR
10. VFD
11. PRESET/TUNE CONTROL KNOB:
12 3456789 10 11
FRONT PANEL
143256 7
REAR PANEL
IMPORTANT NOTES
1. Show the software version
Press “DISPLAY” and “FM/AM”.
2. Light UP all the icon on the VFD
Press “FM/AM” & “PRESET/TUNE”.
3. Factory test resets
When VFD all Light press any key.
4. AM Step 10K/9K Change
When AM band, press “FM MUTE/MODE” & “PRESET/TUNE”.
5. Shipment resets (clear)
When pressing “MEMORY” & “PRESET/TUNE” to VFD all Light, press any key.
- 6 -
5
4
3
1
2
7
6
6
DISASSEMBLY INSTRUCTIONS
1. Remove machine screws M 4.0 x 6.0 ( 1 to 4 ) from the side panels.
Remove tapping screw 3.0 x 8.5 5 from the back panel.
Refer to Figure No.1.
Figure No.1
2. Pull both sides of the TOP COVER slightly outwards 6 and tilt approx. 35˚ and then remove
in the direction as indicated by the arrow 7 . Refer to Figure No.2.
Figure No.2.
- 7 -
BLOCK DIAGRAM
AM LOOP ANT
FM ANT
OUTPUT
FRONT END
ENV172D3G1
VFD
CPU
P89LPC936
U201
U202
VFD DRIVER
PT6311
KEY MATRIX
Trigger IN
U203
EEPROM
24C08
PLL LC72723M
RDS DECODER
U901
AM/FM IF
LA1837
MUTING
IR IN
U701
74HC86
STANDBY
POWER
SUPPLY
RS232
M218
REMOTE
SENSOR
POWER
SUPPLY
VFD
STANDBY 3V3
-VP
+5V CPU
+10V
AC INPUT
RELAY
L
R
VT
VT
ce data clk RDS-CLK RDS-SIG RDS-DATA
MPXIN
data
out
(#1)=Power On
(#2)=Standby
LC7218
U903
ST/MO, MUTE, SMETER
TUNE
FM
OSC/IF
AM
OSC/IF
1
27 17
16
23
2
30
U902
21
2345 15
11
15
8
10 IN
16 14
20
16
14
22
12/13
5
16 19 24
19 18
- 8 -
WIRING DIAGRAM
TRANSFORMER
MAIN board
DSP board
PSU board
LED board KEY board
YELLOW
BLUE
WHITE
7013-0490+0
- 9 -
ADJUSTMENT POINTS DIAGRAM
OSC RF
VT
- 10 -
FM
SIGNAL
GENERATOR
ANTENNA
TERMINAL
OUTPUT
TERMINAL
DISTORTION
METER
DISTORTION
METER
AC
VOLTMETER
OSCILLOSCOPE
AC
VOLTMETER
OR
OSCILLOSCOPE
AC
VOLTMETER
OR
OSCILLOSCOPE
OUTPUT
TERMINAL
OUTPUT
TERMINAL
L
R
ANTENNA
TERMINAL
ANTENNA
TERMINAL
ANTENNA
TERMINAL
AM LOOP
ANTENNA
(Accessory)
AM LOOP
ANTENNA
60cm
DIGITAL
MILLIVOLT-
METER
VT_J911
FM
SIGNAL
GENERATOR
AM
SIGNAL
GENERATOR
FM
SIGNAL
GENERATOR
RDS
GENERATOR
FM
STEREO
GENERATOR
P901
OUTPUT
TERMINAL
DC
MILLIVOLT-
METER
UNIT
UNIT
UNIT
UNIT
INSTRUMENT SETUP
1. FM MEASUREMENT
Fig. 1
Fig. 2
2. RDS MEASUREMENT
Fig. 3
3. AM MEASUREMENT
Fig. 4
- 11 -
ALIGNMENT PROCEDURES
FM/RDS SECTION
- FM mono: 1kHz, 75kHz devi., 60dB/μV
- FM stereo: 1kHz, 67.5kHz devi., 60dB/μV
Pilot signal 19kHz 7.5kHz devi.
OUTPUTS
- Connect the 47Kohm resistor unless otherwise noted.
Item Step Connection
of instrument
FM SG
output
Stereo
modulator
output
Tuning
frequency
Output
indicator
Adjustment
point
Adjust
for Remarks
FM
IF/RF
1
Fig.1
99.0MHz
1kHz 75kHz
devi.
65dBf (60dB)
– 99.0MHz
DC voltmeter L941 0±70mV FM MUTE/MODE
switch: ON/AUTO
Repeat the steps
1 to 3 until no
further adjustment
is necessary.
2 AC voltmeter IFT on the
front end Maximum
3Distortion
analyzer L942 Minimum
Stereo
Distortion Fig.2
99.0MHz Ext.
mod. 65dBf
(60dB)
Channel L
or R 1kHz 99.0MHz Distortion
analyzer
IFT on the
front end Minimum
FM MUTE/MODE
switch: ON/AUTO
Don’t turn more
than ±180˚
Stereo
Separation Fig.2
99.0MHz Ext.
mod. 65dBf
(60dB)
Channel L
or R 1kHz 99.0MHz
Oscilloscope
R941
Maximum
separation
Repeat stereo
distortion and
stereo separation
alignment until
THD at minimum
and separation at
maximum.
Distortion
Meter Minimum
Mute
Level Fig.1 99.0MHz 18dB – 99.0MHz Oscilloscope R956 Signal
output
RDS Fig.3
99.0MHz Ext.
mod. 65dBf
(60dB)
RDS 2% MOD
– 99.0MHz – – –
Decode
the RDS-
Program station
AM SECTION
AF Modulation: 400Hz, 30%
For AH Version
Step AM SG
output
Tuning
frequency
Output
indicator
Adjustment
point
Adjust
for
1 – 530kHz
Digital
DC
voltmeter
OSC coil
on RF
block M971
1.35±0.2V
2
600kHz
400Hz 30% mod.
60dB/m
600kHz AC
voltmeter
RF coil
on RF
block M971
Maximum
3
600kHz
400Hz 30% mod.
60dB/m
990kHz AC
voltmeter L972 Maximum
For C Version
Step AM SG
output
Tuning
frequency
Output
indicator
Adjustment
point
Adjust
for
1–
522kHz
or
531kHz
Digital
DC
voltmeter
OSC coil
on RF
block M971
1.3±0.2V (522kHz)
1.35±0.2V
(531kHz)
2
600kHz
400Hz 30% mod.
60dB/m
603kHz AC
voltmeter
RF coil
on RF
block M971
Maximum
3
600kHz
400Hz 30% mod.
60dB/m
999kHz AC
voltmeter L972 Maximum
- 12-
POWER SUPPLY BOARD
DISPLAY BOARD
LED BOARD
Top side
Top side
Top side
Bottom side
KEY BOARD
Top side
Bottom side
Bottom side
Bottom side
D209
P/N:1726-042A+000B
SECTION:D,ISSUE:B
PCB-C426+LED
LED-ORANGE
KEY-SDBY
LED-BLUE
GND
POWER-ON
LED-ORANGE
J203B2
M207
P/N:1726-042A+000B
SECTION:E,ISSUE:B
P/N:PCB-C426+KEY
J201B
VR201
C231
C230
STOREFM MUTEFM / AM DISPLAY MODE
P/N:1726-042A+000B
BLEND
SECTION:B,ISSUE:B
PCB-C426+DSP
KEY-SDBY
LED-ORANGE
LED-BLUE
GND
U202
J203A
J201A
J1
J4
J5
J6
J7
J8
J9
J10
J11
J12
J13
J14
J15
J16
J17
J18
J19
J20
J21
J26
J27
J28
J29
J30
J31
J32
J33
J34
J35
J36
J37
J38
M210
J202A
J2
J3
C202
C201
C212
C213
C211
C210
R222
R221
R220
R219
Q201
R227
R216
R215
J263
R210
R211
J264
R225
D206
J265
J270
J262
R250
R251
J269
M206
M204
M203
M202
M201 M205
J261
J266
J267
R252
R261
R262
R263
D210
J268
1
13
14
26
27 39
40
52
AC-IN-L
AC-IN-N
GND
GND
POWER-ON
+3V3-SDBY
P/N:1726-042A+000B
SECTION:C,ISSUE:B
PCB-C426+PSU
WHITE BLUE
YELLOW
T1AL 250V AT 230V VERSION
T1.6AL 250V AT 120V VERSION
C103C102
U101
D101
D102
C105
RL101
D106
C106
D105
R103
M103 M104 M105
230V
120V
M101
M102
D104
D103
D107
D108 R104
C111
C107
C109
R105 R106
C110
C101
C104
C116 D109
J101
D301
R301
Q301
J301A
C112
T100
L103
L102
R101
Q302 U116
C100
J103
J105
R108
R102
F101
- 13-
PCB LAYOUT
MAIN BOARD
Top side
13.5
19.5
U902
8.9V
1
AC3.8V
AC3.8V
8V
0V
8V
8.9V
0V
OSC
IF
+B
VT
GND
GND
GND
ANT
M901
U902
8.9V
1
AC3.8V
AC3.8V
8V
0V
8V
8.9V
0V
M901
U204
U701
U201
+3V3-SDBY
POWER-ON
GND
FM-ST
FM-SD
FM-ST
FM-SD
AM-SMETER
FM-SMETER
DATA -IN
CE-PLL
CLK
DATA -OUT
+5V-D
+3V3 +3V3
-VP
-VP
P/N:1726-042A+000B
SECTION:A,ISSUE:B
PCB-C426+MAIN
R-OUT
L-OUT
M302
TRIG-IN IR-IN
M303
C412
C905
C427
L904
M904
L901
U901
M902
R956
R941
R911
L972
L903
U903
R932
L941
L942
L985
P901
M903
R989
L905
0205
R903
R901
R904
R919
R920
R971
R905
R908
R907
R910
R909
R928
R929
R915
R973
R921
R922
R923
R947
R948
R974
C968
C941
D902
R931
R942
R943
R975
R954
R959
R960
R957
R958
R944
R950
R961
R953
R952
R918
R949
R951
R927
R924
J907
J909
J911
J912
J913
J915
J916
J917
J923
J924
J929
J904
J931
J932
J933
J936
J939
J219
J946
D980
J945
J245
R984
R981
J944
J942
R964R963
J401B
D409
D408
D407
D401
D402
J206
J207
J208
J404
J403
U402
M987
G-O
J901
J209
J238
J922
R995
R994
R997
R998
R996
R993
J940
J211
R978
J903
G1
G2
R988
R972
M985
M905
J920
C963
C943
C964
C960 C959
C965
C991
C953
C954
C951
C970
C961
C962
C990C986
C987
C988
C985
C916
C950
C989 C992
Q982
C980
Q981
Q980
Q942
C949
C946
C948
J950
R946
J949
C911
C944
R945
C945
J941
C932
C969
C979
C981
C982
C978
C977
C976
C975
C974
C971
C973
C927
C912
Q922
C913
Q923
C902
C903
C926
C928
C929
Q902
C901
Q901
C904
Q903
C914
C915
C930
C931
C925
C924
Q943 Q944
Q945
C706
D905
R990
Q983
D981
J201
C205
R208
R209
J708
Q984
C216
C217
C221
U203
C219
C425
C417
C416
C421
C407
C409
Q401
Q403
Q402
C414
C413
C415
C405
C406
C411
C410
C402
C403
C404
C203
R404
R401
J406
D412
D411
R403
R402
J958
J202B
C223
C222
J407
C418
D410
J902
J918
J935
J242
J244
D208
R214
R213
J231
J230
R202
J246
J202
R983
J239
J240
R204
R205
J228
J221
J216
J218
J229
J214
J402
J236
R982
J243
R207
R933
J914
C983
C907
C984
J908
J905
D404
D405
D406
J947
J701
J237
J925
R955
C996
C995
R916
J210
J409
J405
R236
Z203
R913
J919
J906
R962
J934
J241
C401
C420
C942
M911
Q702
C701
C702 R701
R702
R705
C707
J235
C408
R707
R706
R708
R418
D903
C966
J910
R902
J921
GND
C999C998
C207
C206
C208
C209
J301B
R986
R985
R987
J955
J952
J956
J926
R999
R991
J418
R992
J411
J930
J951
C994
C993
J953
J204
J232
J948
C215
R968
R969
J234
R235
J223
R203
J928
J927
R906
J417
J227
J233
J225
J215
J412
J413
J414
J416
J415
J213
J220
J224
R912
J954
J957
J212
J217
D403
J938
J943
C220
C906
R228
R212
J226
J205
J222
J401
J203
J247
J248
C908
GND1
GND2
GND3
GND4
GND5
J249
J937
R703
R704
C967
C947
C709
J702
D281
R281
C708
C204
C228
C419
C426
L971C
L971B
L971A
C251
C250
C253
C254
J256
J255
- 14-
MAIN BOARD
Bottom side
18
9
16
114
15 28
1
7
8
14
18
9
16
- 15 -
SCHEMATIC DIAGRAM
KEY / MCU / DISPLAY
NOTE: 1. RESISTORS ARE CARBON FILM 5% 1/8W
UNLESS OTHERWISE SPECIFIED.
2. CERAMIC CAPACITORS ARE 50V 10%
UNLESS OTHERWISE SPECIFIED.
SHEET: 1 OF 3
TITLE:
SIZE: REV:
Revision
Sheet Size
FILE:
NATNC426+09CSXX
Product Code: Customer
NATNC426(A)
NAD
C426 MCU
GND
IR-IN
GND
F1
+3V3-SDBY
F2
+5V-D
STB
CLK
DIN
KEY-B
KEY-A
-VP
KEY2-PCB
+3V3-SDBY
F2
KEY-B
LED-G
KEY-A
-VP
LED-R
GND
GND
LED PCB
KEY1-PCB
F1
IR-IN
+5V-D
STB
CLK
DIN
FM 106.2 MHz
M201
BLEND
M204
MODE
M203
FM MUTE
M202
MEMORY
M205
FM/AM
M206
MODE
J1
J2
J3
J5
J6
J7
J8
J9
J10
J11
J12
J13
J14
J15
J16
J17
J18
J19
J20
J21
J23
J24
J25
J26
J27
J28
J29
J30
J31
J32
J33
J34
J35
J36
J37
J38
M209
VFD
C201
100u
C202
0.01u
1
2
3
45
6
7
8
U203
24C08
C219
0.1U
M210
SENSOR
REMOTE
D209A
GREEN D209B
RED
M213
TRIGGER_IN
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
J202A
D981
1N4148
E
B
C
Q983
C114
R990
1K
R991
47K
T1
T2
R1
R2
C1+
C1-
C2+
C2-
GND
Vcc
V+
V-
12
3
4
5
6
7
89
10
11
1213
14
15
16
U204
MAX232
R214
4K7
C216
100u
C217
104K
6
7
8
9
1
2
3
4
5
J201
DB9
R209 75R
R208 75R
C203
223
C205
104K
C204
100u
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
J202B
C212
100u
C213
0.1U
C210
100u
C211
0.1U
R213
4K7
R204
4K7
R203
4K7
R202
4K7
J22
1
P2.0
2
P2.1
3
P0.0
4
1.7
5
P1.6
6
P1.5
7
VSS
8
P3.1
9
P3.0
10
P1.4
11
P1.3
12
P1.2
13
P2.2
14
P2.3
28 P2.7
27 P2.6
26 P0.1
25 P0.2
24 P0.3
23 P0.4
22 P0.5
21 VDD
20 P0.6
19 P0.7
17 P1.1
18 P1.0
16 P2.5
15 P2.4
U201
P89LCP936
C223
100u
C222
104K
R215
470R
R216
470R
R219
680R
R220
820R
R221
1K8
R222
680R
49
LED2
50
LED1
51
GND
52
OSC
32
GR18
31
SG17
30
SG16
29
SG15
28
SG14
27
SG13
26 SG12
25 SG11
24 SG10
23 SG9
22 SG8
21 SG7
20 SG6
19 SG5
18 SG4
17 SG3
33
VDD
34
VEE
35
GR10
36
GR9
37
GR8
38
GR7
39
GR6
40
GR5
41
GR4
42
GR3
43
GR2
44
GR1
45
VDD
46
LED5
47
LED4
48
LED3
16 SG2
15 SG1
14 VDD
13 K4
12 K3
11 K2
10 K1
9STB
8CLK
7NC
6DIN
5DOUT
4SW4
3SW3
2SW2
1SW1
U202
PT6311
R225
10K
R227
56K
R999
5K1
R212 470R
R228 470R
L201
100uH
203
5V6
R235
4K7
R236
4K7
VR201 J201B
J201A
E
B
C
Q702
2SC1923
R704
1K
R705
10K
R701
1K5
C709
100u
C706
104K
C701
473J
R703
30K
R702
330R
1606
IR_IN
1
1A
2
1B
3
1Y
4
2A
5
2B
6
2Y
7
GND
14 VDD
13 4B
12 4A
11 4Y
10 3B
93A
83Y
U701
74HC86
D701
DAP202K
C702
10u
R706
15K
D903
3V3
C206
104K
C207
104K
C208
104K
C209
104K
D208
SR2100
R288
100R
D210
1N4148
R229
0R
J301B
M207 POWER ON
R252
820R
1
2
3
4
1
2
3
4
J203A
1
2
3
4
1
2
3
4
J203B
R211 120R
R250
4K7 R210
100R
IN
GND
OUT
U3
LM1117-3V3
E
C
B
Q201
DTC114
SG18
SG17
SG16
SG15
SG14
SG13
SG12
SG11
SG10
SG09
SG08
SG07
SG06
SG05
SG04
SG03
SG02
SG01
SG17
SG16
SG15
SG14
SG13
SG12
SG11
SG10
SG09
SG08
SG07
SG06
SG05
SG04
SG03
SG02
SG01
+3V3-SDBY
POWER-ON
GND
GND
GND
GND
GND
GND
GND
GND
GND
GND
GND
GND
-VP
GND
+3V3-SDBY
+5V-D
RDS-CLK
RDS-DATA
AM-SMETER
FM-SMETERFM-STEREO
FM-SD
DATA-OUT
GND
TUNER-MUTE
CE-PLL
CLK
DATA-IN
POWER-ON
CHGND
SG[01:18]
GND
DATA-OUT
- 16 -
TUNER
NOTE: 1. RESISTORS ARE CARBON FILM 5% 1/8W
UNLESS OTHERWISE SPECIFIED.
2. CERAMIC CAPACITORS ARE 50V 10%
UNLESS OTHERWISE SPECIFIED.
SHEET: 2 OF 3
TITLE:
SIZE: REV:
Revision
Sheet Size
Company Name
FILE: NATNC426(A)
Product Code: Customer
NATNC426+09CSXX NAD
C426 TUNER
GND
GND
FM
GND
1
2
3
ANT
GND
ANT
7
4
6
8
IF
GND
B+
OSC
5
VT
NMRF-5077
MITSUMI FE450-G11
R901 R904 R907 R903 R905 R908 R975 R959 R960 C901 C961 C962 Q901
3K3 - - 1K - - 33K 120K 120K - 332 332 -
33K 330 3K3 12K 680 470 56K 270K 270K 223 152 152 2SC945A-P
AH
C
R957
4K3
3K
R958
4K3
3K
TUNER_L
TUNER_R
M971
M901
FM_SD
(M)
(M)
(M)
(M)
(M)
(M)
SEP.
(M)
R960
*
C964
22U/16V
1
FM_I
2
AM_MIX_O
3
FM_I_BYPASS
4
AM_I
5
GND
6
TU
7
ST
8
VCC
9FM_DETECT
10
AM_NARROW
11
FM_S_O
12
AM_S_O
13
IF_BUFF
14
PHASE_COMP
15
PILOT_DETECT
16
R_O
17
L_O
18
R_I
19
L_I
20
R_MPX_O
21
L_MPX_O
22
MPX_I
23
FM_DM_O
24
AM_DETECT_O
25
AM_AGC
26
AFC
27
AM_RF_I
28
REG
29
OSC
30
OSC_BUFF
U901
LA1837
R963
100K
R959
*
C961
*
R957
*
R958
*
C962
*
C963
22U/16V
C959
10U/16V
C960
10U/16V
R961
470R
R962
470R
R964
100K
E
C
BQ944
2SD1468A
Q943
2SD1468A
C953
272J
C954
272J
C951
10U/16V
R954
10K
R975
*
C979
10U/16V
C970
223
1
2
3
R941
22K
C976 223Z
C977
10U/16V
1
2
P901
C978
223Z
C975
10U/16V
C974
223Z
R973
18K
C971
8P (NPO) R972
10K
C973
473J
C982
101J
C981
223Z
C949
223Z
E
C
B
Q942
2SC1740S
R949
3K3
R951
1K
R950
680K
C950
223Z
E
C
B
Q945
DTA114ES
R968
1K
C967
10U/16V
C948
1U/50V
R948
10K
C947
0.47U
50V
C946
1U/50V
R946
3K3
R945
10K
R947
10K
C968
223Z
C969
47U
16V
C943
2u2
50V
3
2
1
M911
CST12
450JL3
R974
100K
C941
223Z
C942
1000U
16V
D902
9.1V
1/2W
R931
22E
C932
223Z
C944
4.7u
50V
R944
100K
C945
101J
R943 8K2
R942
4K7
R913
0R
M985
4.332MHz
C989
30P (NPO)
C988
30p (NPO)
C985
561
C987
223Z
C986
6V3
100u
C990
6V3
100u
R987 1K
R986 1K
R985 1K
L985
100uH
R953 22K
R952
22K
R922
1K
R921
1K
C925
20P (NPO)
C924
20P (NPO)
R923
1K
C930 223Z
C931
100U/6V3
R924
1K
C927
2u2/50V
C926
333J
B
C
EQ923
2SC1740S
R929
3K3
R928
220
R927
10K
C929
0.22U/16V
C928
10U/16V
13
2
M902
SFE10.7MA5
R902
22E
R901
*
B
C
E
Q901
*
C901
*
13
2
M903
SFE10.7MA5
R904
*
R908
*
R907
*
B
C
E
Q902
2SC1923-0
R909
330E
R910
330E
13
2
M904
SFE10.7MA5
C902
223Z
C903
223Z
1003
C904
10U/16V
R579
100K
68
2200p
5p
100K
0.018u
1.5p
2200p
100K
3
1
4
6
5p
27p
470K
470p
8p
10K
100E 0.018u
15p
330E
330K
5p
10E 220
330E
22p
1K8
10K
5p
0.7p
2K7
82p
0.018u
22E
10K
1
3
4
L941
NFIF-4081
4
6
1
3
L942
NFIF-4082
M971-A
M971-B
M971-C
1
2
3
4
6
L903 *
NMC-4085
4
6
1
2
3
L972
NMIF-4062
1
2
3
4
6
L904 *
NMC-4085
R956
10K
C965
272K
C906
100U/16V
R903
*R905
*
R911
100
C991
102
C916
330p
L901
22uH
R906
10K
C911
20p
B
C
E
Q922
2SC1740S
C912
102
C913
102
M905 7.2MHz
R916
1K
R918
4K7
C914
100p
C915
100p
R919
1K
R920
1K
E
C
B
Q903
DTA114ES
RDSID/READY
RDCL
RDDA
RST
MODE
VDDD
VSSD
XIN XOUT
TEST
CIN
FLOUT
VSSA
VDDA
MPXIN
VREF 1
2
3
4
5
6
7
89
10
11
12
13
14
15
16
U902
LC72723
L905
100uH
C992
0.01u
1XIN
2CE
3DI
4CL
5DD
6SYC
7IN0
8IN1
9OUT0
10 OUT1
11 OUT2
12 OUT3 13
OUT4
14
OUT5
15
LCTR
16
HCTR
17
OUT6
18
AMIN
19
FMIN
20
VDD
21
PD1
22
PD2
23
VSS
24
XOUT
U903
LC7218
R915
10K
E
C
B
Q980
DTC114
R989
10K
E
C
BQ981
DTA114
R983
100K
Q982
2SK363BL
D980
1N4148
R984
1M
R988
470 C980
224K
R981
100
R995
100k
R996
0R
R993
100K
R994
100k
R998
0R
R997
100K
R969
100K
E
C
BQ984
C114
R992
2K2
R912
100uH
J965
1N4001
R955
100uH
C966
223K
C998
152K
C999
152K
C994
152K
C993
152K
GND
GND
+9V
+5V-D
+9V
+5V-D
+9V
-9V
+12V
FM_STEREO
FM_SD
TUNER-MUTE
RDS_SIG
RDS-DATA
RDS_CLK
AM-SMETER
FM-SMETER
DATA-IN
CLK
CE-PLL
DATA-OUT
- 17 -
PSU
PIN=2.54mm
MAIN Transformer
120V/ONLY
230V ONLY
" ARE SAFETY CRITICAL PARTS.
3 COMPONENTS MARKED "
2 CERAMIC CAPACITORS, ARE 50V 10% 0805. UNLESS OTHERWISE SPECIFIED.
NOTE:1 RESISTORS, ARE METAL FILM 5% UNLESS OTHERWISE SPECIFIED.
CE 230V/50Hz
UL 120V/60Hz
CONNECT AGND TO DGND
AC3.8V
AC3.8V
8V
8V
0V
8.9V
8.9V
0V
D411
10V C407
16V
22U
E
C
B
Q402
2SA950Y
C408
16V
2200u
C409
16V
220u
C405
16V
2200u
C406
16V
1000u
D403
1N4001
D404
1N4001
D405
1N4001
D406
1N4001
C404
223K
C402
223K
C403
223K
C413
25V
220U D407
1N4001
D409
1N4001
D408
1N4001
C414
50V
100u
C415
50V
100u
R402
1K
R403
10
R401
1K
E
C
B
Q401
2SA950Y
D410
27V
C416
50V
100u
C417
50V
100u
C418
50V
100u
D402
1N4001
D401
1N4001
C410
0.1u
C411
0.1u
C412
16V
100u
C401
223K
1
2
3
4
5
6
7
8
J401
C419
10V
47u
B
C
E
Q403
8050
D412
10V
C421
16V
47u
R404
1K
AC INPUT
IN
GND
OUT
U402
78M05
R418
47K
D101
1N4007
D102
1N4007
D103
1N4007
D104
1N4007
C102
400V
4.7U
L102
27uH
C103
400V
4.7U
C105
16V
10U
D107
UF4006
D106
1N4007
C106
25V
47U
R103
2K7 1/4W
D105
UF4006
R102 100K/1W
C104 103M/400V
1
2
U103-A
3
4
U103-B
EL817A
R104
1K
D108
UF4006
U102
TL431
C107
25V
470U
C110
25V
100U
C109
103K R105
12K
R106
22K
L103
27uH
C116
472M 400V
T101
D109
1N4007
C100
472M
400V
4
3
5
RL101-A
1
2
RL101-C
C101
472M/400V
M104
M105
M103
T201
120/230V
1
2
3
4
5
6
7
8
J4
Q301
A42
D301
IN4007
M101
M102
J301A
R301
120R
C112
1000P
C111
104K
1VCC
2NC
3NC
4FB 5
DRAIN
7
NC
8
GND
U101
E
C
B
Q302
DTC114
F101
T1A 230V only
T1.6A 120V only
R108
3M3 1/2W
230V only
POWER-ON
+3V3-SDBY
+5V-D
GND
+3V3-SDBY
POWER-ON
F2
F1
-9V
+9V
-VP
+3V3-SDBY
GND
H-GND
J103
Change jumper to 100R 1W MOX/FP
Part # 4718-101J-1-P
- 18 -
Serial
Data
Interface
DIN
DOUT
CLK
STB
VDD
R
OSC
SW1
SW2
SW3
SW4
LED1
LED2
LED3
LED4
LED5
K1 K2 K3 K4 VDD GND VEE
SG1/KS1
OSC
General
Input
Register
LED
Driver
Dimming Circuit
Grid
Driver
Segment
Driver
Grid
Driver
Key Scan
Output
Control
Dispaly Memory
Timing Generator
Key Matrix Memory
SG2/KS2
SG3/KS3
SG4/KS4
SG5/KS5
SG6/KS6
SG7/KS7
SG8/KS8
SG9/KS9
SG10/KS10
SG11/KS11
SG12/KS12
SG13/GR16
SG14/GR15
SG15/GR14
SG16/GR13
SG17/GR12
SG18/GR11
SG19/GR10
SG20/GR9
GR1
GR2
GR3
GR4
GR5
GR6
GR7
GR8
IC BLOCK DIAGRAM
DSP Board
U202: PT6311
- 19 -
Main Board
U201: P89LCP936
ACCELERATED 2-CLOCK 80C51 CPU
4 kb/8 kB/16 kB
CODE FLASH
256-BYTE
DATA RAM
PORT 2
CONFIGURABLE I/Os
PORT 1
CONFIGURABLE I/Os
PORT 0
CONFIGURABLE I/Os
KEYPAD
INTERRUPT
PROGRAMMABLE
OSCILLATOR DIVIDER
CPU
clock
CONFIGURABLE
OSCILLATOR
ON-CHIP
RC
OSCILLATOR
internal bus
CRYSTAL
OR
RESONATOR
POWER MONITOR
(POWER-ON RESET,
BROWNOUT RESET)
UART
ANALOG
COMPARATORS
512-BYTE
AUXILIARY RAM
I2C-BUS
512-BYTE
DATA EEPROM
(P89LPC935/936)
PORT 3
CONFIGURABLE I/Os
CCU (CAPTURE/
COMPARE UNIT)
(P89LPC935/936)
P89LPC933/934/935/936
WATCHDOG TIMER
AND OSCILLATOR
TIMER 0
TIMER 1
REAL-TIME CLOCK/
SYSTEM TIMER
SPI
ADC1/DAC1
ADC0/DAC0
(P89LPC935/936)
P3[1:0]
P2[7:0]
P1[7:0]
P0[7:0]
X2
X1
TXD
RXD
SCL
SDA
T0
T1
CMP2
CIN2B
CIN2A
CMP1
CIN1A
CIN1B
OCA
OCB
OCC
OCD
ICA
AD10
AD11
AD12
AD13
DAC1
AD00
AD01
AD02
AD03
DAC1
ICB
SPICLK
MOSI
MISO
SS
P89LPC935FDH
P89LPC936FDH
1
2
3
4
5
6
7
8
9
10
11
12
13
14
16
15
18
17
20
19
22
21
24
23
26
25
28
27
P2.0/ICB/DAC0/AD03
P2.1/OCD/AD02
P0.0/CMP2/KBI0/AD01
P1.7/OCC/AD00
P1.6/OCB
P1.5/RST
VSS
P3.1/XTAL1
P3.0/XTAL2/CLKOUT
P1.4/INT1
P1.3/INT0/SDA
P1.2/T0/SCL
P2.2/MOSI
P2.3/MISO
P2.7/ICA
P2.6/OCA
P0.1/CIN2B/KBI1/AD10
P0.2/CIN2A/KBI2/AD11
P0.3/CIN1B/KBI3/AD12
P0.4/CIN1A/KBI4/DAC1/AD13
P0.5/CMPREF/KBI5
VDD
P0.6/CMP1/KBI6
P0.7/T1/KBI7
P1.0/TXD
P1.1/RXD
P2.5/SPICLK
P2.4/SS
- 20 -
VCC 8
7
4
6
5
3
2
1
GND
WP
SCL
LOAD
LOAD INC
DATA WORD
ADDR/COUNTER
Y DEC
X DEC
R/W
COMP
SERIAL
CONTROL
LOGIC
EN H.V. PUMP/TIMING
DATA RECOVERY
EEPROM
SERIAL MUX
DOUT/ACK
LOGIC
DEVICE
ADDRESS
COMPARATOR
START
STOP
LOGIC
SDA
A
2
A
1
A
0
DIN
DOUT
Main Board
U203: AT24C08A-10PU
Main Board
U204: MAX232D
Main Board
U402: NJM78M56FA
1
INPUT
3
OUTPUT
2
GND
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
C1+
V+
C1–
C2+
C2–
V–
DOUT2
RIN2
VCC
GND
DOUT1
RIN1
ROUT1
DIN1
DIN2
ROUT2
Main Board
U206: NCP1117ST33T3G
132
ADJ/GND V
OUT
V
IN
Main Board
U701: 74HC86 1
2
3
4
5
6
7
14
13
12
11
10
9
8
1A
1B
1Y
2A
2B
2Y
GND
VCC
4B
4A
4Y
3B
3A
3Y
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
ALC AM
OSC
AM
MIX
AM
RF.AMP
REG
AGC
AM IF
AM
S-METER
TUNING
DRIVE
STEREO
DRIVE
VCC
VCC
AM/FM
IF-BUFF
FM
S-METER S-CURVE
AM IF FM
DET
GND
FM IF INPUT
AM MIXER
OUTPUT
FM IF INPUT
BYPASS
AM IF INPUT
GND
TU-LED
ST LED
AM-IF OUTPUT
FM DETECTOR
A
M NARROW CF
FM S-METER
OUTPUT
AM S-METER
OUTPUT
MUTE
FM/AM
SWITCH
PILOT VCO
SD
COMP
DET
BUFF
DECODER
ANTI-BIRIDE
3 rd 5 th
STEREO
SW
MUTE
VCO
304kHz
FF
38k
P-DET
Ø
FM SD
ADJ
OSC
REG
AM RF
INPUT
AFC
AM AGC
AM DETECTOR
INPUT
FM DETECTOR
OUTPUT
MPX
IUTPUT
MPX
OUTPUT
MPX
OUTPUT
AM STEREO L
INPUT
AM STEREO R
INPUT
L-OUT
R-OUT
FF
19k
FF
19k
PILOT
DET
Main Board
U901: LA1837L-E
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