Panasonic SA-AK78 User manual

■Amplifier Section
Front speaker power output
Power output
PMPO 3400 W
RMS power output
THD 10%, both channels driven
Total 200 W per channel (6Ω)
LOW 100 Hz 120 W per channel (6Ω)
MID 1 kHz 40 W per channel (6Ω)
HIGH 10 kHz 40 W per channel (6Ω)
Power output in
Dolby Pro Logic mode
PMPO Total 4000 W
RMS power output
THD 10%
Total 500 W
Front LOW 100 Hz 120 W per channel (6Ω)
Front HIGH 1 kHz 40 W per channel (6Ω)
Center 1 kHz 90 W per channel (8Ω)
Surround 1 kHz 45 W per channel (8Ω)
Input sensitivity
AUX 1, AUX 2 250 mV
MIC 0.7 mV
© 2000 Matsushita Electronics (S) Pte. Ltd. All rights
reserved. Unauthorized copying and distribution is a
violation of law.
SA-AK78
Colour
(S)... Silver Type
Area
(GC)... Asia, Latin America, Africa and Middle Near
East
TAPE SECTION
AR2 MECHANISM SERIES
CD SECTION
RAE0152Z-3 TRAVERSE DECK SERIES
Input impedance
AUX 1, AUX 2 10 kΩ
MIC 600 Ω
■FM Tuner Section
Frequency range 87.50-108.00 MHz (50 kHz step)
Sensitivity 1.8µV (IHF)
S/N 26 dB 1.5µV
Antenna terminal(s) 75 Ωunbalanced
■AM Tuner Section
Frequency range 522-1629 kHz (9kHz step)
520-1630 kHz (10kHz step)
Sensitivity
S/N 20 dB 500 µV/m
■Cassette Deck Section
Track system 4 track, 2 channel
Heads
Record/playback Solid permalloy head
Erasure Double gap ferrite head
Motor DC servo motor
Recording system AC bias 100kHz
Erasing system AC erase 100kHz
Tape speed 4.8 cm/s
CD Stereo System
Specification
ORDER NO. MD0005090C3

Overall frequency reponse (+3, -6
dB at DECK OUT)
NORMAL (TYPE I) 35- Hz - 14 kHz
HIGH (TYPE II) 35- Hz - 14 kHz
S/N 50dB (A weighted)
Wow and flutter 0.18 % (WRMS)
Fast forward and rewind time Approx. 120 seconds with C-60
cassette tape
■CD Section
Sampling frequency 44.1kHz
Decoding 16 bit linear
Frequency response 20 Hz - 20 kHz (+1, -2 dB)
Wow and flutter Below measurable limit
Digit filter 8fs
D/A converter MASH (1 bit DAC)
■General
1 Before Use 2
2 Before Repair and Adjustment 2
3 Protection Circuitry 2
4 Accessories 3
5 Handling Precautions For Traverse Deck 4
6 Precaution of Laser Diode 4
7 Operation Procedures 6
8 Self-Diagnostic Display Function 8
9 Description of Error Code 9
Power supply AC 110V/127V/220V/230-240V,
50/60Hz
Power consumption 188 W
Standby
ECO 0.8 W
NORMAL 12 W
Dimensions (WxHxD) 270 x 330 x 339 mm
Weight 8.8 kg
Notes :
1. Specifications are subject to change without notices.
Weight and dimensions are approximate.
2. Total harmonic distortion is measured by the digital spectrum
analyzer.
■System: SC-AK78 (GC) Music Center : SA-AK78 (GC)
Front Speaker : SB-AK78 (GC)
Center Speaker : SB-PC70 (GC)
Surround Speaker : SB-PS70 (GC)
10 CD Test Mode Function 10
11 Measurements and Adjustments 11
12 Terminal Function of IC’s 13
13 Block Diagram 16
14 Schematic Diagram 26
15 Printed Circuit Board 47
16 Wiring Connection Diagram 57
17 Troubleshooting Guide 59
18 Parts Location and Replacement Parts List 60
CONTENTS
Page Page
1 Before Use
Be sure to disconnect the mains cord before adjusting the voltage selector. Use a minus (-) screwdriver to set the voltage selector
(on the rear panel) to the voltage setting for the area in which the unit will be used. (If the power supply in your area is 117V or
120V, set to the “127V” position.) Note that this unit will be seriously damaged if this setting is not made correctly. (There is no
voltage selector for some countries; the correct voltage is already set.)
2 Before Repair and Adjustment
Disconnect AC power, discharge Power Supply Capacitors C566 - C569, C591 through a 10Ω, 5W 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 110V, 127V, 220V, 230-240V, 50 Hz in NO SIGNAL mode should be ~620mA, ~590mA, ~330mA
and ~300mA respectively.
3 Protection Circuitry
The protection circuitry may have operated if either of the following conditions are noticed:
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4 Accessories
Remote Control
Transmitter
AC power supply cord
FM indoor antenna
AM Loop antenna
Power plug
adaptor
••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.
Note : Refer to Packing Materials & Accessories for part number.
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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).
●Handling of 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.
To connect to the PC board, be sure to open by
removing the solder build-up, and finish the work
quickly.
3.Take care not to apply excessive stress to the flexible
board (FFC board).
4.Do not turn the variable resistor (laser power
adjustment). It has already been adjusted.
●Grounding for electrostatic breakdown prevention
1.Human body grounding
Use the anti-static wrist strap to discharge the static
electricity from your body.
2.Work table grounding
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).
Caution when Replacing the Traverse Deck :
The traverse deck 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.
5 Handling Precautions For Traverse Deck
6 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 : 780 nm
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.
ACHTUNG :
Dieses Produkt enthält eine Laserdiode. Im eingeschalteten Zustand wird unsichtbare Laserstrahlung von der Lasereinheit
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■Use of Caution Labels
abgestrahlt.
Wellenlänge : 780nm
Maximale Strahlungsleistung der Lasereinheit :100W/VDE
Die Strahlung an der Lasereinheit ist ungefährlich, wenn folgende Punkte beachtet werden:
1.Die Lasereinheit nicht zerlegen, da die Strahlung an der freigelegten Laserdiode gefährlich ist.
2.Den werkseitig justierten Einstellregler der Lasereinhit nicht verstellen.
3.Nicht mit optischen Instrumenten in die Fokussierlinse blicken.
4.Nicht über längere Zeit in die Fokussierlinse blicken.
ADVARSEL: I dette a apparat anvendes laser.
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.
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8.7. Power Amplifier Failure (F61)
8 Self-Diagnostic Display Function
8.1. Self-diagnostic display
This unit is equipped with a self-diagnostic display function which, if a problem occurs, will display an error code corresponding to
the problem.
Use this function when performing maintenance on the unit.
8.2. How to enter the Self-Diagnostic Function
1.Turn the unit on with no cassette in the deck. (Select the tape function)
2.Press and hold the “STOP/TUNE MODE” button for at least 2 seconds.
3.While pressing the “STOP/TUNE MODE” button, press “FF/MEMORY” button for at least 2 seconds.
4.“T” will appear on the FL display. (unit is in the Self-Dianostic Function)
8.3. Cassette Mechanism Test (For error code H01, H02, H03, F01, F02)
1.Press “TAPE, DECK 1/2” to select Deck 2.
2.Load a cassette tape with the erasure prevention tab, remove from left side only and close the cassette holder.
3.Press “FAST FORWARD MEMORY/NEXT” (Tape will be stop after 2 seconds)
4.Load a cassette tape with the erasure prevention tab, remove from right side only and close the cassette holder.
5.Press “REVERSE FM MODE/BP/PREV” (Tape will be stop after 2 seconds)
6.Load a pre-recorded tape with both side record tabs intact and close the cassette holder.
7.Press “PLAY TUNE/TIME ADJ SELECT” (After TPS function, tape will stop automatically)
8.Press “REC/STOP” (Tape will not move)
9.Press “STOP TUNE MODE” to indicate Error code.
••If several problem exist, error code will change each time when “■TUNE MODE/PBC” is pressed.
(e.g. H01 →H03 →F01 .....etc.)
10.Press “TAPE, DECK 1/2” to select Deck 1.
11.Repeat step 2 to 9 to test Deck 1. (Tape Deck 1 will not check H02 because of no recording function)
8.4. CD Mechanism Test (F15, F26, F16, F17, F27, F28, F29, H15, F75)
1.Press “CD”.
2.Press “CD MANAGER”.
3.Press “■TUNE MODE” to indicate Error Code.
••If several problem exist, error code will change each time when “■STOP TUNE MODE” is pressed. (e.g. F15 →F26 →F16
..... etc.)
8.5. To clear all Error code
1.Press “STOP TUNE MODE/PBC” button for 5 seconds.
2.FL indicator shows “CLEAR” for 1 second and change to “T”.
8.6. How to get out from Self-Diagnostic function
1.Press “Power” button OFF.
1.When power amplifier fail, F61 will indicate automatically.
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9 Description of Error Code
9.1. Error detection for Cassette Mechanism block
No. Error Error
Display Problem condition
1 MODE SW
detection error H01 Faulty operation of cassette mechanism. Faulty contact or short-circuit of mechanism mode switch (S951, S971).
2REC INH SW
detection error H02 Recording not possible. Faulty contact or short-circuit of REC INH switch (S974, S975).
3HALF SW
detection error H03 Playback cannot perform. Faulty contact or short-circuit of HALF siwtch (S952, S972).
4Reel Pulse
detection error F01 The tape advances slightly and then stops. Faulty reel pulse, faulty hole detect IC (IC951, IC971).
5TPS abnormal F02 Cassette deck will not perform TPS function.
Faulty playback EQ/recording amplifier IC (IC101).
9.2. Error detection for CD/Changer block
No. Error Error
Display Problem condition
1REST SW detection error F15 CD does not function.
This error occurs when the Optical Pick Up REST SW (S701) is not
detected within the specified time (about 8 seconds)
2CD tray opens automatically F16 CLAMP switch (S4) NG (Check & Replace)
3Does not startup when [PLAY]
button is pressed F17 BOTTOM switch (S5) NG (Check & Replace)
4Transmission error between CD
servo LSI and micon F26 CD does not function. This error occurs when the POWER is ON for the CD block and an error
is
detected after the transmission has started.
5Startup fails even when you
insert CD or the selected disc tray
does not open
F27 Tray 1 detect switch or Tray 2 detect switch NG (Check & Replace)
6Cannot insert CD F28 Tray 1 detect switch NG (Check & Replace)
7Cannot eject CD F29 Check if disc is stuck. Tray 2 detect switch NG (Confirm & Replace)
8CD power error F75 CD does not function.
Check if CDRST is H for SELECTOR at CD. If it is not H after 1 second,
it shall be memorised as an error. (IC702)
9The CD tray closes H15 CD disc tray detect switch NG (S3) (Check & Replace)
9.3. Power Supply related error detection
No. Error Error
Display Problem condition
1POWER AMP
output abnormal F61 When POWER is switched on, power become off automatically. During normal operation, if DC DET become L, PCNT shall become
L and the error display on the left shall be displayed. (IC501)
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10 CD Test Mode Function
This CD test mode is provided to check CD unit without connecting to changer loading mechanism. This mode shall operate CD
PLAY with CD unit being connected only and CD Automatic Alignment result is shown on FL display.
10.1. How to enter the Self-Diagnostic Function
1.Turn the unit on and select the CD function.
2.Press and hold the “STOP/TUNE MODE” button for at least 2 seconds.
3.While pressing the “STOP/TUNE MODE” button, press “FF/MEMORY” button for at least 2 seconds.
4.“ ” will appear on the FL display. (unit is in the CD test mode)
10.2. CD Automatically Adjustment result indication
Under CD test mode, pressing the numeric key ‘0’ on the remote controller will display the auto adjustment result. FLOCK, TLOCK
and CLVS status shall be shown as below:
During the above display, executing CD PLAY will display auto adjustment result for CD PLAY mode.
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