NAD C 445 User manual

NAD
C 445
FM / AM
DAB TUNER
C 445 CFM / AM DAB TUNER
SERVICE MANUAL

PRODUCT SAFETY SERVICING GUIDELINES
CAUTION : DO NOT ATTEMPT TO MODIFY THIS PRODUCT IN
ANY WAY. NEVER PERFORM CUSTOMIZED INSTALLATIONS
WITHOUT MANUFACTURER’S APPROVAL. UNAUTHORIZED
MODIFICATIONS WILL NOT ONLY VOID THE WARRANTY, BUT
MAY LEAD TO YOUR BEING LIABLE FOR ANY RESULTING
PROPERTY DAMAGE OR USER INJURY.
SERVICE WORK SHOULD BE PERFORMED ONLY AFTER YOU
ARE THOROUGHLY FAMILIAR WITH ALL OF THE FOLLOWING
SAFETY CHECKS AND SERVICING GUIDELINES. TO DO
OTHERWISE, INCREASES THE RISK OF POTENTIAL HAZARDS
AND INJURY TO THE USER.
WHILE SERVICING, USE AN ISOLATION TRANSFORMER FOR
PROTECTION FROM AC LINE SHOCK.
SAFETY CHECKS
AFTER THE ORIGINAL SERVICE PROBLEM HAS BEEN
CORRECTED. A CHECK SHOULD BE MADE OF THE
FOLLOWING.
SUBJECT : FIRE & SHOCK HAZARD
1. BE SURE THAT ALL COMPONENTS ARE POSITIONED IN
SUCH A WAY AS TO AVOID POSSIBILITY OF ADJACENT
COMPONENT SHORTS. THIS IS ESPECIALLY IMPORTANT
ON THOSE MODULES WHICH ARE TRANSPORTED TO AND
FROM THE REPAIR SHOP.
2. NEVER RELEASE A REPAIR UNLESS ALL PROTECTIVE
DEVICES SUCH AS INSULATORS, BARRIERS, COVERS,
SHIELDS, STRAIN RELIEFS, POWER SUPPLY CORDS, AND
OTHER HARDWARE HAVE BEEN REINSTALLED PER
ORIGINAL DESIGN. BE SURE THAT THE SAFETY PURPOSE
OF THE POLARIZED LINE PLUG HAS NOT BEEN DEFEATED.
3. SOLDERING MUST BE INSPECTED TO DISCOVER POSSIBLE
COLD SOLDER JOINTS, SOLDER SPLASHES OR SHARP
SOLDER POINTS. BE CERTAIN TO REMOVE ALL LOOSE
FOREIGN PARTICLES.
4. CHECK FOR PHYSICAL EVIDENCE OF DAMAGE OR
DETERIORATION TO PARTS AND COMPONENTS. FOR
FRAYED LEADS, DAMAGED INSULATION (INCLUDING AC
CORD). AND REPLACE IF NECESSARY FOLLOW ORIGINAL
LAYOUT, LEAD LENGTH AND DRESS.
5. NO LEAD OR COMPONENT SHOULD TOUCH A RECEIVING
TUBE OR A RESISTOR RATED AT 1 WATT OR MORE. LEAD
TENSION AROUND PROTRUDING METAL SURFACES MUST
BE AVOIDED.
6. ALL CRITICAL COMPONENTS SUCH AS FUSES,
FLAMEPROOF RESISTORS, CAPACITORS, ETC. MUST BE
REPLACED WITH EXACT FACTORY TYPES, DO NOT USE
REPLACEMENT COMPONENTS OTHER THAN THOSE
SPECIFIED OR MAKE UNRECOMMENDED CIRCUIT
MODIFICATIONS.
7. AFTER RE-ASSEMBLY OF THE SET ALWAYS PERFORM AN
AC LEAKAGE TEST ON ALL EXPOSED METALLIC PARTS OF
THE CABINET, (THE CHANNEL SELECTOR KNOB, ANTENNA
TERMINALS. HANDLE AND SCREWS) TO BE SURE THE SET
IS SAFET TO OPERATE WITHOUT DANGER OF ELECTRICAL
SHOCK. DO NOT USE A LINE ISOLATION TRANSFORMER
DURING THIS TEST USE AN AC VOLTMETER, HAVING 5000
OHMS PER VOLT OR MORE SENSITIVITY, IN THE
FOLLOWING MANNER; CONNECT A 1500 OHM 10 WATT
RESISTOR, PARALLELED BY A .15 MFD, 150V AC TYPE
CAPACITOR BETWEEN A KNOWN GOOD EARTH GROUND
(WATER PIPE, CONDUIT, ETC.) AND THE EXPOSED
METALLIC PARTS, ONE AT A TIME.
MEASURE THE AC VOLTAGE ACROSS THE COMBINATION
OF 1500 OHM RESISTOR AND .15 MFD CAPACITOR.
REVERSE THE AC PLUG AND REPEAT AC VOLTAGE
MEASUREMENTS FOR EACH EXPOSED METALLIC PART.
VOLTAGE MEASURE MUST NOT EXCEED 75 VOLTS R.M.S.
THIS CORRESPONDS TO 0.5 MILLIAMP AC ANY VALUE
EXCEEDING THIS LIMIT CONSTITUTES A POTENTIAL
SHOCK HAZARD AND MUST BE CORRECTED IMMEDIATELY.
SUBJECT : GRAPHIC SYMBOLS
SUBJECT : TIPS ON PROPER INSTALLATION
1. NEVER INSTALL ANY PRODUCT IN A CLOSED-IN RECESS,
CUBBYHOLE OR CLOSELY FITTING SHELF SPACE. OVER
OR CLOSE TO HEAT DUCT, OR IN THE PATH OF HEATED
AIR FLOW.
2. AVOID CONDITIONS OF HIGH HUMIDITY SUCH AS:
OUTDOOR PATIO INSTALLATIONS WHERE DEW IS A
FACTOR, NEAR STEAM RADIATORS WHERE STEAM
LEAKAGE IS A FACTOR, ETC.
3. AVOID PLACEMENT WHERE DRAPERIES MAY OBSTRUCT
REAR VENTING. THE CUSTOMER SHOULD ALSO AVOID THE
USE OF DECORATIVE SCARVES OR OTHER COVERINGS
WHICH MIGHT OBSTRUCT VENTILATION.
4. WALL AND SHELF MOUNTED INSTALLATIONS USING A
COMMERCAL MOUNTING KIT MUST FOLLOW THE FACTORY
APPROVED MOUNTING INSTRUCTIONS A PRODUCT
MOUNTED TO A SHELF OR PLATFORM MUST RETAIN ITS
ORIGINAL FEET (OR THE EQUIVALENT THICKNESS IN
SPACERS) TO PROVIDE ADEQUATE AIR FLOW ACROSS
THE BOTTOM, BOLTS OR SCREWS USED FOR FASTENERS
MUST NOT TOUCH ANY PARTS OR WIRING. PERFORM
LEAKAGE TEST ON CUSTOMIZED INSTALLATIONS.
5. CAUTION CUSTOMERS AGAINST THE MOUNTING OF A
PRODUCT ON SLOPING SHELF OR A TILTED POSITION,
UNLESS THE PRODUCT IS PROPERLY SECURED.
6. A PRODUCT ON A ROLL-ABOUT CART SHOULD BE STABLE
ON ITS MOUNTING TO THE CART. CAUTION THE
CUSTOMER ON THE HAZARDS OF TRYING TO ROLL A CART
WITH SMALL CASTERS ACROSS THRESHOLDS OR DEEP
PILE CARPETS.
7. CAUTION CUSTOMERS AGAINST THE USE OF A CART OR
STAND WHICH HAS NOT BEEN LISTED BY UNDERWRITERS
LABORATORIES, INC. FOR USE WITH THEIR SPECIFIC
MODEL OF TELEVISION RECEIVER OR GENERICALLY
APPROVED FOR USE WITH T.V.’S OF THE SAME OR
LARGER SCREEN SIZE.
8. CAUTION CUSTOMERS AGAINST THE USE OF EXTENSION
CORDS, EXPLAIN THAT A FOREST OF EXTENSIONS
SPROUTING FROM A SINGLE OUTLET CAN LEAD TO
DISASTROUS CONSEQUENCES TO HOME AND FAMILY.
THE LIGHTNING FLASH WITH ARROWHEAD SYMBOL, WITHIN AN
EQUILATERAL TRIANGLE, IS INTENDED TO ALERT THE USER TO THE
PRESENCE OF UNINSULATED “DANGEROUS VOLTAGE” WITHIN THE
PRODUCT’S ENCLOSURE THAT MAY BE OF SUFFICIENT MAGNITUDE TO
CONSTITUTE A RISK OF ELECTRIC SHOCK.
THE EXCLAMATION POINT WITHIN AN EQUILATERAL TRIANGLE IS
INTENDED TO ALERT THE USER TO THE PRESENCE OF IMPORTANT
OPERATING AND MAINTENANCE (SERVICING) INSTRUCTIONS IN THE
LITERATURE ACCOMPANYING THE APPLIANCE.
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FM SECTION
Frequency Range: 87.50 MHz to 108.00 MHz
(50 kHz steps)
Signal-to-Noise Ratio: 65dB (Mono) 60dB (Stereo)
Presets: 30
AM SECTION
Frequency Range: 522 kHz to 1620 kHz (9 kHz steps)
Signal-to-Noise Ratio: 35dB
Presets:
DAB SECTION
Band lll: 174MHz - 240MHz
Band L : 1452MHz - 1492MHz
Max signal: ~ -3dBm
Sensitivity: -96dBm
Adjacent Channel Rejection: ~ 35dB
Presets:      
Display: 2-line by 16-character DOT Matrix
Audio Output Stereo: 2.5V P-P
48kHz sample rate, 16 bit sample resolution
Optical S/PDIF: IEC60958 Compliant.
48kHz sample rate, 24 bit sample resolution
GENERAL
Power Requirement: 230-240V AC, 50Hz
Power Consumption: 12W 0.8W(standby)
DIMENSIONS (MAX)
Width Height Depth: 435 x 86 x 318mm
Weight:
30
~
99
6kg
SPECIFICATIONS
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This unit is designed for trouble-free operation. Most problems users encounter are due to operating errors. If you have a problem, first check this list
for a possible solution. If the problem persists, consult your authorized Service Centre.
Symptom Cause/Correction
No lights appear when System Power button is pressed Unit is plugged into a live outlet.
Make sure the outlet is active.
No sound is heard Tune to an active station.
Check for correct amplifier settings.
Check the connections and wires.
Sound distorts, particularly in stereo mode. Use a more directional antenna.
Intermittent or continuous buzzing or hissing Place the unit further away from these appliances.
Install noise filters on the appliances.
Display says 'No stations Available' Check that antenna is connected.
Ensure that DAB coverage exists in your area.
Display has gone blank or says 'service off air' This may occur if a broadcaster changes the label of a service or removes a label
whilst you are listening to it. Try to retune to this station, using the Autotune
procedure.
Unit's operation or the displays seem abnormal To correct this problem, first unplug the unit from the AC wall outlet and wait at
least three minutes. After the pause, reconnect the AC power cord and check the
unit's operation.
Reset the C445 Tuner; press and hold the Menu/FM Mute Button for 5 seconds,
until the Information Display shows FACTORY RESET. Note that when the system
is reset, all tuner presets will be lost and must be re-entered.
Press the RESET switch lightly once or twice with a pencil or ballpoint pen as per
example below.
If these steps do not solve the problem, consult your dealer or an authorized
service centre.
Rear Panel
TROUBLESHOOTING
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MAINTENANCE FLOW CHART
Start
Power on
Voltages NO 1. Check Cable
at pins of connector 2. Replace Power Supply unit if Power Board is not shorted,
(CN93) are normal? otherwise find out first where the short is.
YES
NO NO Check CNVMB114MA18L
Are FM/AM Is Power Supply (Tuner Module)
MAIN Board normal? normal? and peripheral circuit.
(CUP11866Y)
YES
NO
Is PLL Check S3F84BB
Clock normal? and peripheral circuit.
YES YES
Chcek TUNER module connection Antenna.
Power Board
(CUP11866Y)
NO NO Check DAB Module
Is DAB Is Power Supply and peripheral
normal? normal? circuit.
YES
NO Check 74ACT04(IC73) or
Is Voltage level 74LVC04(IC74) and
normal? peripheral circuit.
MAIN Board YES
(CUP11866Y)
YES NO Check S3F84BB or DAB
Are Clock and Module and peripheral
Data normal? Circuit.
YES
Check DAB Module connection Antenna.
Normal Operation
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WIRING DIAGRAM
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Terminal assignment
Relay - top view
Non-latching type,
not energized condition
latching, 2 coils
reset condition
Latching type,
reset condition
FP2 Relay (RT21)
1
2
3
4
8
7
6
5
V+
Out B
–In B
+In B
Out A
–In A
+In A
V–
OPA2134
8-Pin DIP, SO-8
A
B
BLOCK DIAGRAM (IC22, IC23, IC24: OP AMP)
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PIN CONNECTION AND IEC LOGIC SYMBOLS
INPUT AND OUTPUT EQUIVALENT CIRCUIT PIN DESCRIPTION
TRUTH TABLE
PIN No SYMBOL NAME AND FUNCTION
1, 3, 5, 9, 11,
13 1A to 6A Data Inputs
2, 4, 6, 8, 10,
12 1Y to 6Y Data Outputs
7 GND Ground (0V)
14 VCC Positive Supply Voltage
AY
LH
HL
HEX INVERTER (IC73: 74ACT04)
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Terminal Functions (IC21: PCM1796)
TERMINAL
I/O
DESCRIPTIONS
NAME PIN
I/O
DESCRIPTIONS
AGND1 19 − Analogground (internal bias)
AGND2 24 − Analog ground (internal bias)
AGND3L 27 − Analog ground (L-channel DACFF)
AGND3R 16 − Analog ground (R-channel DACFF)
BCK 6 I Bit clock input(1)
DATA 5 I Serial audio data input(1)
DGND 8 − Digital ground
IOUTL+ 25 O L-channel analog current output+
IOUTL– 26 O L-channel analog current output–
IOUTR+ 17 O R-channel analog current output+
IOUTR– 18 O R-channel analog current output–
IREF 20 − Output current reference bias pin
LRCK 4 I Left and right clock (fS) input(1)
MC 12 I Mode control clock input(1)
MDI 11 IMode control data input(1)
MDO 13 I/O Mode control readback data output(3)
MS 10 I/O Mode control chip-select input(2)
MSEL 3 I I2C/SPI select(1)
RST 14 I Reset(1)
SCK 7 I System clock input(1)
VCC1 23 − Analog power supply, 5 V
VCC2L 28 − Analog power supply (L-channel DACFF), 5 V
VCC2R 15 − Analog power supply (R-channel DACFF), 5 V
VCOML 22 − L-channel internal bias decoupling pin
VCOMR 21 − R-channel internal bias decoupling pin
VDD 9 − Digital power supply, 3.3 V
ZEROL 1 I/O Zero flag for L-channel(2)
ZEROR 2 I/O Zero flag for R-channel(2)
(1) Schmitt-trigger input, 5-V tolerant
(2) Schmitt-trigger input and output. 5-V tolerant input and CMOS output
(3) Schmitt-trigger input and output. 5-V tolerant input. In I2C mode, this pin becomes an open-drain 3-state output; otherwise, this pin is a CMOS
output.
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FUNCTIONAL BLOCK DIAGRAM (IC21: PCM1796)
Power Supply
RST
SCK
Advanced
Segment
DAC
Modulator
IOUTL+
IOUTL−
IOUTR−
Current
Segment
DAC IOUTR+
Bias
and
Vref
VCOML
VCOMR
AGND2
VDD
VCC1
VCC2L
VCC2R
AGND1
I/V and Filter
8
Oversampling
Digital
Filter
and
Function
Control
Audio
Data Input
I/F
LRCK
BCK
DATA
MDO
MDI
MC
MS
AGND3L
AGND3R
DGND
Current
Segment
DAC
IREF
VOUT
L
I/V and Filter
VOUT
R
Function
Control
I/F
MSEL
Zero
Detect
ZEROL
ZEROR System
Clock
Manager
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PIN ASSIGNMENTS(IC21: PCM1796)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
28
27
26
25
24
23
22
21
20
19
18
17
16
15
ZEROL
ZEROR
MSEL
LRCK
DATA
BCK
SCK
DGND
VDD
MS
MDI
MC
MDO
RST
VCC2L
AGND3L
IOUTL−
IOUTL+
AGND2
VCC1
VCOML
VCOMR
IREF
AGND1
IOUTR−
IOUTR+
AGND3R
VCC2R
PCM1796
(TOP VIEW)
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RESET IC (RE5VL28CATZ) : IC72
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IC71 FUNCTION (MI-COM S3F84BB)
Pin No. PIN NAME I/O DESCRIPTION
1~8 FIP-DA O FIP Data output port
9 N.C - Non connection
10 SINO I UART Data input port
11 SOTO O UART Data output port
12 VDD1 I Power supply port(+5V)
13 VSS1 I GND
14 XTOUT O 10MHz crystal connection port
15 XIN I
16 TEST I Back-up Input
17,18 N.C - Non connection
19 RESET I Reset input port("L")
20 N.C - Non connection
21 DAB_DIN I DAB Data input port
22 DAB_DOUT O DAB Data output port
23 DAB_CLK O DAB Clock control port("L")
24 FM/AM_MUTE O FM/AM MUTE control port("L")
25 PLL_DATA O PLL Data output port
26 PLL_CE O PLL Enable control port
27 PLL_CLK O PLL Clock control port
28 STEREO I Tuner module stereo control port
29 TUNED I Tuner module tuned control port
30 PLL_DIN I PLL Data input port
31 RDS_CLK O RDS Clock control port
32 RDS_DATA I RDS Data input port
33 BACK_UP I BACK-UP mode control port("L")
34 REMOTE_IN I Remote unit data input port
35~38 N.C - Non connection
39,40 GND I GND
41 SCROLL_UP I Scroll up control port
42 SCROLL_DN I Scroll down control port
43 VREF I A/D converter reference voltage
44 AVSS I
GND
45 GND I
46 KEY3 I
47 KEY2 I
48 KEY1 I KEY 1 control port
49~51 N.C - Non connection
52 VSS2 I GND
53 VDD2 I Power supply port(+5V)
54 SYSTEM_MUTE O System MUTE control port("L")
55 STAND_BY O Standby on control port("L")
56 FM/AM_ON O FM/AM on control port("L")
57 N.C - Non connection
58 POWER_ON O Unit turn on control port("L")
59~64 N.C - Non connection
65~68 OPTION I GND or OPEN
69~70 N.C - Non connection
71 OPTION I GND or OPEN
72~74 N.C - Non connection
75 OPTION I GND or OPEN
76~77 N.C - Non connection
78 RS_P O Register selection port
79 WRITE O Write enable port
80 READ O Read enable port
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BLOCK DIAGRAM (IC71: S3F84BB)
I/O Port and Interrupt Control
SAM88RC CPU
64K-Byte
ROM 2064-Byte RAM
OSC/RESETB
8-Bit
Basic Timer
8-Bit
Timer
/CounterA,B
8-Bit
Timer/
CounterC0,C1
16-Bit
Timer
/Counter10,11
Port 0 Port 1A/D
Port 2 P2.0-P2.7
XIN
XOUT
RESETB
P2.7/TAOUT
P2.6/TACAP
P2.5/TACK
P3.6/TCOUT1
P2.4/TBOUT
P3.4/T1OUT0
P1.0-P1.7P0.0-P0.7 AVREF AVSS
Port 3 P3.0-P3.7
Port 4 P4.0-P4.7/
INT0~INT7
Port 5 P5.0-P5.7
Port 6 P6.0-P6.7
SIO/
UART0,1
PG
P3.7/TCOUT0
P0.0~P0.7/
PG0~PG7
P3.2/T1CAP0
P3.0/T1CK0
P3.5/T1OUT1
P3.3/T1CAP1
P3.1/T1CK1
P2.2/SCK
P2.1/SI
P2.0/SO
P5.3/RXD0
P5.2/TXD0
P5.1/RXD1
P5.0/TXD1
Port 8 Port 7D/A
P7.0-P7.7/
ADC0~ADC7
P8.0-P8.5/
INT8,INT9 P2.3/ DAOUT
Figure 1-1. S3C84BB/F84BB Block Diagram
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