Panasonic SC-EN38GCS User manual

I
AMPLIFIER SECTION
RMS
OUTPUT POWER both channel driven simultaneously
10%
total harmonic distortion (THD)
1
kHz 3 W per channel (6 Ω)
PMPO
Output Power 90 W
Input
Music Port
Sensitivity
100 mv, 15 kΩ
Terminal
Stereo, 3.5 mm jack
Output
Headphone
Terminal
Stereo, 3.5 mm jack
(16 Ωto 32 Ω)
Option
Port Version 1
I
TUNER SECTION
Frequency
range
FM
87.50 MHz to 108.00 MHz
(50 kHz)
AM
522 kHz to 1629 kHz (9 kHz)
520 kHz to 1630 kHz (10 kHz)
I
DISC SECTION
Disc
played [8cm or 12cm]
(1)
CD-Audio (CD-DA)
(2)
CD-R/RW (CD-DA, MP3)
(3)
MP3
Sampling
frequency
CD
44.1 kHz
© 2008 Matsushita Electric Industrial Co. Ltd.. All
rights reserved. Unauthorized copying and
distribution is a violation of law.
SC-EN38GCS
Colour
(K)... Black Type
MP3 32 kHz, 44.1 kHz, 48 kHz
Bit rate
MP3 32 kbps to 384 kbps
Decoding 16/20/24 bit linear
Pick up
Wavelength 785 nm
Laser power CLASS 1
Audio Output (Disc)
Number of channels 2 channel
Audio performance
Frequency response (CD-Audio) 20 Hz to 20 kHz
Wow and flutter Below measurement limit
Digital filter 8
D/A converter MASH (1 bit DAC)
IUSB SECTION
Media file format support MP3 (*.mp3)
Power consumption in standby mode:
2.6 W (approx.)
ISPEAKER SECTION
Type 1 Way, 1 speaker system
(Bass reflex)
Speaker (s)
Full range 7 cm cone type
CD Stereo System
Specifications
ORDER NO. MD0804001CE

Impedance 6Ω
Input power (IEC) 3W(MAX)
Dimension (W x H x D) 120 mm x 202.8 mm x 133.5 mm
IGENERAL
Power supply AC 220 to 240 V, 50 Hz
Power consumption 30 W
Dimension (W x H X D) 252.5mm x 202.8mm x 133.5 mm
Mass
With speakers Approx. 3.20 kg
1 Safety Precautions 3
2 Prevention of Electro Static Discharge (ESD) to
Electrostatically Sensitive (ES) Devices 5
3 Precaution of Laser Diode 6
4 Handling Precautions For Traverse Deck 7
5 Handling the Lead free Solder 8
6 Accessories 9
7 Operation Procedures 10
8 Self diagnosis and special mode setting 14
9 Assembling and Disassembling 19
10 Service Fixture and Tools 46
Without speakers Approx. 1.90 kg
Operating temperature range 0°Cto+40°C
Operation humidity range 35% to 80% RH (no condensation)
Notes:
• Specifications are subject to change without notice.
• Total harmonic distortion is measured by the digital spectrum
analyzer.
ISystem : SC-EN38GCS-K Main Unit: SA-EN38GCS-K
Speaker: SB-EN38P-K
11 Service Position 47
12 Voltage Measurement & Waveform Chart 53
13 Wiring Connection Diagram 59
14 Block Diagram 61
15 Notes Of Schematic Diagram 65
16 Schematic Diagram 67
17 Printed Circuit Board 77
18 Illustration of IC’s, Transistors and Diodes 81
19 Terminal Function of IC’s 82
20 Exploded Views 85
21 Replacement Parts List 89
CONTENTS
Page Page
2
SC-EN38 GCS

1.1.2. Leakage Current Hot Check
1 Safety Precautions
1.1. General Guidelines
1. When servicing, observe the original lead dress. If a short circuit is found, replace all parts which have been overheated or
damaged by the short circuit.
2. After servicing, ensure that all the protective devices such as insulation barriers, insulation papers shields are properly installed.
3. After servicing, check for leakage current checks to prevent from being exposed to shock hazards.
1.1.1. Leakage Current Cold Check
1. Unplug the AC cord and connect a jumper between the two prongs on the plug.
2. Using an ohmmeter measure the resistance value, between the jumpered AC plug and each exposed metallic cabinet part on
the equipment such as screwheads, connectors, control shafts, etc. When the exposed metallic part has a return path to the
chassis, the reading should be between 1MΩand 5.2Ω.
When the exposed metal does not have a return path to the chassis, the reading must be .
1. Plug the AC cord directly into the AC outlet. Do not use an isolation transformer for this check.
2. Connect a 1.5kΩ, 10 watts resistor, in parallel with a 0.15µF capacitors, between each exposed metallic part on the set and a
good earth ground such as a water pipe, as shown in Figure 1.
3. Use an AC voltmeter, with 1000 ohms/volt or more sensitivity, to measure the potential across the resistor.
4. Check each exposed metallic part, and measure the voltage at each point.
5. Reverse the AC plug in the AC outlet and repeat each of the above measurements.
6. The potential at any point should not exceed 0.75 volts RMS. A leakage current tester (Simpson Model 229 or equivalent) may
be used to make the hot checks, leakage current must not exceed 1/2 milliamp. should the measurement is outside of the limits
specified, there is a possibility of a shock hazard, and the equipment should be repaired and re-checked before it is returned
to the customer.
Fig. 1
3
SC-EN38 GCS

1.2. Before Repair and Adjustment
Disconnect AC power, discharge Power Supply Capacitors C501 through a 10Ω, 1W resistor to ground.
DO NOT SHORT-CIRCUIT DIRECTLY (with a screwdriver blade, for instance), as this may destroy solid state devices.
After repairs are completed, restore power gradually using a variac, to avoid overcurrent.
• Current consumption at AC 230-240 V, 50 Hz in NO SIGNAL mode should be ~300 mA.
1.3. Protection Circuitry
The protection circuitry may have operated if either of the following conditions are noticed:
• No sound is heard when the power is turned on.
• Sound stops during a performance.
The function of this circuitry is to prevent circuitry damage if, for example, the positive and negative speaker connection wires are
"shorted", or if speaker systems with an impedance less than the indicated rated impedance of the amplifier are used.
If this occurs, follow the procedure outlines below:
1. Turn off the power.
2. Determine the cause of the problem and correct it.
3. Turn on the power once again after one minute.
Note:
When the protection circuitry functions, the unit will not operate unless the power is first turned off and then on again.
1.4. Safety Part Information
Safety Parts List:
There are special components used in this equipment which are important for safety.These parts are marked by in the
Schematic Diagrams & Replacement Parts List. It is essential that these critical parts should be replaced with manufacturer’s
specified parts to prevent shock, fire or other hazards. Do not modify the original design without permission of manufacturer.
Table 1
Reference No. Part No. Part Name & Description Remarks
A2 K2CQ2CA00007 AC CORD [M]
A2 K2CP2CA00001 AC CORD [M]
JK600 K2AA2B000017 AC INLET [M]
T600 G4CYAYY00176 TRANSFORMER [M]
F1 K5D202BLA013 FUSE [M]
L600 ELF15N035AN LINE FILTER [M]
301 RAE0165T-V TRAVERSE UNIT (W/O CD SERVO
P.C.B)
[M] (RTL)
FP600 K5G302AA0002 FUSE PROTECTOR [M]
FP841 K5G251A00008 FUSE PROTECTOR [M]
R260 ERD2FCVG470T 47 1/4W [M]
PCB6 REPX0652F TRANSFORMER P.C.B [M] (RTL)
PCB7 REPX0652F AC INLET P.C.B [M] (RTL)
4
SC-EN38 GCS

2 Prevention of Electro Static Discharge (ESD) to
Electrostatically Sensitive (ES) Devices
Some semiconductor (solid state) devices can be damaged easily by electricity. Such components commonly are called
Electrostatically Sensitive (ES) Devices. Examples of typical ES devices are integrated circuits and some field-effect transistors and
semiconductor “chip” components. The following techniques should be used to help reduce the incidence of component damage
caused by electro static discharge (ESD).
1. Immediately before handling any semiconductor component or semiconductor-equiped assembly, drain off any ESD on your
body by touching a known earth ground. Alternatively, obtain and wear a commercially available discharging ESD wrist strap,
which should be removed for potential shock reasons prior to applying power to the unit under test.
2. After removing an electrical assembly equiped with ES devices, place the assembly on a conductive surface such as aluminium
foil, to prevent electrostatic charge build up or exposure of the assembly.
3. Use only a grounded-tip soldering iron to solder or unsolder ES devices.
4. Use only an anti-static solder remover device. Some solder removal devices not classified as “anti-static (ESD protected)” can
generate electrical charge to damage ES devices.
5. Do not use freon-propelled chemicals. These can generate electrical charges sufficient to damage ES devices.
6. Do not remove a replacement ES device from its protective package until immediately before you are ready to install it. (Most
replacement ES devices are packaged with leads electrically shorted together by conductive foam, aluminium foil or
comparable conductive material).
7. Immediately before removing the protective material from the leads of a replacement ES device, touch the protective material
to the chassis or circuit assembly into which the device will be installed.
Caution
Be sure no power is applied to the chassis or circuit, and observe all other safety precautions.
8. Minimize body motions when handling unpackaged replacement ES devices. (Otherwise harmless motion such as the brushing
together of your clothes fabric or the lifting of your foot from a carpeted floor can generate static electricity (ESD) sufficient to
damage an ES device).
5
SC-EN38 GCS

3 Precaution of Laser Diode
Caution :
This product utilizes a laser diode with the unit turned "ON", invisible laser radiation is emitted from the pick up lens.
Wavelength : 785 nm (CD)
Maximum output radiation power from pick up : 100 µW/VDE
Laser radiation from pick up unit is safety level, but be sure the followings:
1. Do not disassemble the optical pick up unit, since radiation from exposed laser diode is dangerous.
2. Do not adjust the variable resistor on the pick up unit. It was already adjusted.
3. Do not look at the focus lens using optical instruments.
4. Recommend not to look at pick up lens for a long time.
CAUTION!
THIS PRODUCT UTILIZES A LASER.
USE OF CONTROLS OR ADJUSTMENTS OR PERFORMANCE OF PROCEDURES OTHER THAN THOSE SPECIFIED HEREIN MAY RESULT
IN HAZARDOUS RADIATION EXPOSURE.
6
SC-EN38 GCS

The laser diode in the traverse deck (optical pickup) may break
down due to potential difference caused by static electricity of
clothes or human body.
So, be careful of electrostatic breakdown during repair of the
traverse deck (optical pickup).
GHandling of CD traverse deck (optical pickup)
1. Do not subject the traverse deck (optical pickup) to
static electricity as it is extremely sensitive to electrical
shock.
2. The short land between the No.4 (LD) and No.5 (GND)
pins on the flexible board (FFC) is shorted with a solder
build-up to prevent damage to the laser diode.
3. Take care not to apply excessive stress to the flexible
board (FFC board) (Fig 4.1).
4. Do not turn the variable resistor (laser power
adjustment). It has already been adjusted.
Fig 4.1
GGrounding for electrostatic breakdown prevention
1. Human body grounding (Fig 4.2)
Use the anti-static wrist strap to discharge the static
electricity from your body.
2. Work table grounding (Fig 4.2)
Put a conductive material (sheet) or steel sheet on the
area where the traverse deck (optical pickup) is placed,
and ground the sheet.
Caution :
The static electricity of your clothes will not be grounded
through the wrist strap. So, take care not to let your
clothes touch the traverse deck (optical pickup).
Fig 4.2
Caution when Replacing the Optical Pickup :
The traverse has a short point shorted with solder to protect
the laser diode against electrostatics breakdown. Be sure to
remove the solder from the short point before making
connections.
4 Handling Precautions For Traverse Deck
7
SC-EN38 GCS

5 Handling the Lead free Solder
5.1. General description about Lead Free Solder (PbF)
The lead free solder has been used in the mounting process of all electrical components on the printed circuit boards used for this
equipment in considering the globally environmental conservation.
The normal solder is the alloy of tin (Sn) and lead (Pb). On the other hand, the lead free solder is the alloy mainly consists of tin
(Sn), silver (Ag) and Copper (Cu), and the melting point of the lead free solder is higher approx.30 degrees C (86°F) more than that
of the normal solder.
Definition of PCB Lead Free Solder being used
The letter of “PbF” is printed either foil side or components side on the PCB using the lead free solder.
(See right figure)
Service caution for repair work using Lead Free Solder (PbF)
• The lead free solder has to be used when repairing the equipment for which the lead free solder is used.
(Definition: The letter of “PbF” is printed on the PCB using the lead free solder.)
• To put lead free solder, it should be well molten and mixed with the original lead free solder.
• Remove the remaining lead free solder on the PCB cleanly for soldering of the new IC.
• Since the melting point of the lead free solder is higher than that of the normal lead solder, it takes the longer time to melt
the lead free solder.
• Use the soldering iron (more than 70W) equipped with the temperature control after setting the temperature at 350±30
degrees C (662±86°F).
Recommended Lead Free Solder (Service Parts Route.)
• The following 3 types of lead free solder are available through the service parts route.
RFKZ03D01K-----------(0.3mm 100g Reel)
RFKZ06D01K-----------(0.6mm 100g Reel)
RFKZ10D01K-----------(1.0mm 100g Reel)
Note
* Ingredient: Tin (Sn), 96.5%, Silver (Ag) 3.0%, Copper (Cu) 0.5%, Cobalt (Co) / Germanium (Ge) 0.1 to 0.3%
8
SC-EN38 GCS

Remote
control
AC cord
AC cord (For
Thailand only)
AM antenna
Support stand
AC Clamp
Filter
6 Accessories
Note : Refer to Packing Materials & Accessories (Section 21) for part number.
9
SC-EN38 GCS

7 Operation Procedures
7.1. Main Unit & Remote Control Key Buttons Operation
10
SC-EN38 GCS