Panasonic SC-H M900 User manual

ROZMO121
Service Manual
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SC-HM900
SB-PS70
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SB-HM900 SA-HM900
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Stereo system
SC-H M900
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SB-HM900
ESPECIFICA TIONS
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Notes:
1. AIIthe informationaresubjecttochangewithoutnotice.
2. Weigthanddimensionsareapproximate.
,...... Panasonic (illol!@
DIGITAL AUDIO
MODEL UNIT
SA-HM900 Stereo
SC-HM900 SB-HM900 Front Speaker
SB-PS70 Surround Speaker
SB-PC70 Cantar Speaker
POWEROUTPUT(AMPLlFIER)
Front (Low) 130W RMS par ehannel (6 Q), 80 Hz , 10% DAT
(High) 70 W RMS par ehannel (6 Q), 1 kHz , 10% DAT
Surround 50W RMS par ehannel (8 Q), 1 kHz, 10% DAT
Central 100W RMS (8Q), 80 Hz, 10 % DAT
AMPlIFIER SA-HM900
Power output: 7000 W PMPO
Power eonsumption: 280 W
Supply: 127V ea :t10% 60 Hz
Input sensitivity: 250 mV
Freeueney ranga AM: 522 - 1629 kHz (9 kHz steps )
520 -1630 kHz (10kHz steps)
Freeueney ranga FM: 87,5 - 108,0 MHz (50 kHz steps )
Dimensions (b x h xl): 360 x 425 x 340 mm
Weight: 9,8 kg approx.

SC-HM900 I
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Lh WARNING
This service information is designed for experienced repair technicians only and is not designed for use bythe general
publico
It does not contain warnings or cautions to advise non-technical individuals of potential dangers in attempting to
service a product. Producís powered by electricity should be serviced or repaired only by experienced professional
technicians. Any attempt to service or repair the porduct or producís dealt with in this service information by anyone
else could result in serious injury or death. ~
CONTENTS
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
page
Safety Precaution 3
Before Repair and Adjustment 4
Protection Circuitry 4
Accessories 4
Handling Precautions For Traverse Deck 5
Precaution of Laser Diode '6
Operation Procedures""""""" 7
Operation Checks and Main Component Replacement Procedures 9
Self-Diagnostic Function """""' 17
Descriptionof ErrorCede"""""""" 18
Cd Test Mode Function """"""""""" 19
Measurements and Adjustments """"""' 20
lIIustration of IC, Transistors and Diodes :23
Terminal Function of IC 24
Block Diagram "" 27
Schematic Diagram 35
Printed Circuit Board 48
Wiring Connection Diagram """""""' 59
TroubleshootingGuide"""""""""" 60
París Location and Replacement París List 61
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PSPEAKERS INPUT DIMENSIONS WEIGHT
IMPEDANCE (b x h x 1)
SB-HM900
FRONT 355 x 560 x 340 mm 9,2 Kg aprox.
Super Tweeter 3cm - - - - -- -- -
Tweeter 6cm - -- -- - - - -
Woofer 17 cm - -- -- - - - -
Super Woofer 30 cm - -- - - - -- -
(high) 612 - - - -- -
(Iow) 612 - - - -- -
SB-PS70
SURROUND
FuI!Range 8 cm 812 170 x 106x 118 mm 0,9 Kg aprox.
SB-PC70
CENTER 812 250x121 x147mm 1,6 Kg aprox.
Tweeter 6cm
Woofer 10 cm A

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1SC-HM900
1Safety Precaution
1.
2.
3.
4-
5.
Before Servicing, unplug the power cord to prevent an electric shock.
When replacing parts, use only manufacture's recommended components for safety.
Check the condition of the power cardoReplace if wear or damage is evident.
After servicing, be sure to restore the lead dress, insulation barriers, insulation papers, shields, etc.
Before returningthe serviced equipment to the customer, be sure to make the following insulation resistance test to
prevent the customer from being exposed to a shock hazard.
1.1 Insulation Resistance Test
1.
2.
3.
Unplug the power cord and short the two prongs of the plug with a jumper wire.
Turn on the power switch.
Measure the resistancevalue with ohmmeter between thejumper AC plug and each exposed metal cabinet part, such
as screwheads, antenna, control shafts, handle brackets, etc.
Equipment with antenna terminals should read between 3MQ and 5.2MQ to all exposed parts* (Fig.1).
Equipment without antenna terminals should read approximately infinity to all exposed parts. (Fig.2).
*Note: Some exposed parts may be isolated from the chassis by designoThese will read infinity.
4. If the measurement is outside the specified limits, there is a possibility of a shock hazard. The equipment should be
repaired and rechecked before it is returned to the customer.
Exposed
metal,./'/
par!
Fig.1
Resistance ==3MO - 5.2MO
Exposed
metal/'
par!
Fig-:2
Resistance==Approx 00
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SC-HM900 J
2Before Repair and Adjustment
Disconnect AC power, discharge Power Supply Capacitors POWER PCB C556, C557, C558, C559, C561 and TRANS-
FORMER PCB C705 through a 10 Q, 5W resistorto ground.
DO NOT SHORT-CIRCUIT DIRECTLy (with a screwdriver blade, for instance), as this way destroy salid state devices.
After repairs are completed, restore power gradually using a variac, to avoid overcurrent.
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Current consumption at AC 127V, 60Hz in NO SIGNAL mode should be ~800mA.
3Protection 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:
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1.
2.
3.
Turn off the power.
Determine the cause of the problem and correGíit.
Turn on the power once again after one minute.
Note:
Whentheprotectioncircuitryfunctions,theunitwillnotoperateunlessthepowerisfirstturnedoffandthenonagain.
4Accessories '""
Ac cord 1 pza
(SJA168-1A) DtR~~~~~~~)""""""""""""""""""""" 1 pza
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Df~s~~~~~-~)""""""""""""""""""""" 1 pza DBattery(remote control) 2 pzas
(UM-3PA)
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DtRMM~~~~~~support 1 pza D ~~2~ol~~~~~~113)""""""""""""""""" 1 pza
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[SC-HM900
5Handling Precautions For Traverse Deck
f'" 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 pick up).
Handling of traverse deck (optical pick up)
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 (LO)and No. 5 (GND)pins on the flexible board (FFC) is shorted with a solde build-
up to prevent damage tothe laserdiode. To connect to the PC board besure to open by removing the solder build-up
and finish the work quickly.
3. Take Gafenot to apply excessive stress to the flexible board (FFC).
4. Do not turn the variable resistor (laser power adjustment). It has already been adjusted.
Flexible board.
FFC
(Handle it carefully)
\
Lens
(Donottouch)
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/
No.@Pin(GND) No.@)Pin(LO) Variable resistor
(Do not lum)
Grounding for electrostatic breakdown prevention
1. Human body groundling
Use the anti-satatic wrist strap to discharge the static electricity from your body.
Work table grounding
Pul a conductive material (sheet) or steel sheet on the afea where the traverse deck (optica! pickup) isplaced, and
ground the sheet.
r2.
Caution:
The static electricity of your clothes will not be groundedthrough the wrist strap. So,take Gafenot to leí your clothes touch
the traverse deck (optical pickup).
Caution when Replacing the Traverse Deck:
The traverse deck has a short point shourted with solder to proteGíthe lazer diode against electrostatics breakdown. Be
sure to remove the solder from the short point before making connections.
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Wriststrap
(Anti-static bracelet)
Iron plate or some metals
to conduct electricity
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SC-HM900]
6Precaution 01 Laser Diode
CAUTION:
This unit utilizes a class 1 laser.
Invisible laser radiation is emitted from the optical pick up lens.
When the unit is turned on:
1. Do not look directly into the pick up lens.
2. Do not use optical instruments to look at tlle pick up lens.
3. Do not adjust the preset variable resistor on the pick up lens.
4. Do not disassemble the optical pick up unit.
5. If the optical pick up is replaced use the manufactures's specified replacement pick up only.
6. Use of control or adjustments or performance of procedures other than those specified here in may result in hazard-
ous radiation exposure.
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CAUTION!
THIS PRODUCT UTILlZES A LASER.
USE OF CONTROLS OR ADJUSTMENTS OR PERFORMANCE OF PROCEDURES OTHER THAN THOSE SPECI
FIED HERE IN MAY RESULT IN HAZARDOUS RADIATION EXPOSURE.
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7Operation Procedures
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ISC-HM900
aMain unit
No. Name
CD Ac supply indicator (AC IN)
(This indicalor lighls when Ihe unil is connecled lo Ihe AC power supply)
(]) Standby/on switch (6/1 POWER)
Press lo switch Ihe unil Irom on lo slandby mode or viceversa. In slandby
mode, Ihe unil is slill consuming a small amounl 01 power.
@ Play timer/record timer button (e) PLAY/ e) REC)
@ Clock/timer button (CLOCKlTIMER)
@ Signal sensor
@ 6ch button (6 CH INPUT)
(j) Karaoke select button KARAOKE
@ Microphone volume control (MIC VOL)
@ Microphone jacks 1 y 2
@ Deck 1 open button ( ~ DECK 1 OPEN)
@ Deck 1 cassette holder
@ Disc tray
@ Cd manager button (CD MANAGER)
@J Disc direct play and indicators (1 - 5)
@ Disc tray open/close button ( ~ )
@ Super 3d ai button (SUPER 3D Al)
@ Super sound eq button (SUPER SOUND Ea)
@ Sound equalizer knob (SOUND Ea)
@ Sound equalizer control (SOUND Ea)
@ Volume control (VOLUME DOWN UP)
@ Headphones jack (PHONES)
~Deck 2 open button ( ~ DECK 2 OPEN)
eDeck 2 cassette holder
rn Consola central
~Aux select button (AUX 1/2)
@ Tuner/band select button (TUNER BAND)
@ Tape/deck select button (DECK 1/2 TAPE)
@ Cd button (CD)
@ Display
@ Reverse mode select button (REV MODE)
@ Tape edil button (TAPE EDIT)
@ Dolby pro logic button ( [][JPRO LOGIC)
@ Display selectldemostration button (-DISPLAY/-DEMO)
@ Recording button ( . REC/STOP)
@ Surround button (SURROUND)
@ Super woofer on/off button (S. WOOFER)
@ Basic operating button
(Funclions change according lo Ihe source)
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SC-HM900 ]
IRemote control
Numberssuch asO, lunction is exactlythe same way as the buttons on
the main unit and the number such as @, lunction only with remate
control.
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No. Nombre
f) Standby/on button ( <!>)
@Auto power-off (AUTO OFF)
@Numeric buttons (;::: 10,1-9, O)
@Program button (PROGRAM)
@Cancel button (CANCEL)
~Aux selector button (AUX 1/2)
eTuner/band select button (TUNER)
G) Eq select button (Ea)
e3d ai button (3D Al)
a. Dolby Pro Logic button ([][] PL)
@Play/pause/preset channel select button (only lor cd play)
(""/11IV )
@Test button (TEST)
@Channel selector button (CH SELECT)
G> Volume buttons (- VOLUME +)
@Sleep button (SLEEP)
@Muting button (MUTING)
@Disc button (DISC)
@Random button (RANDOM)
@Repeat button (REPEAT)
GDisc button (CD)
eTape/deck selct button (TAPE)
@Skip/search bullan ( 1+11/"-, ~/~ )
@Play/preset channel select ( ~/¡\)
~Stop/clear program melodies (8/CLEAR)
@Channellevel selector buttons (- CH LEVEL +)
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ISC-HM900
8Operation Checks and Main Component Replacement
Procedures
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IGear for servicing (jig) informationI
1. This unít has a gear which is usedfor checking items (open/close of disc tray, up/down operation of traverse unit by
manually) when servicing.
2. For preparation of gear (for servicing), Perform the procedures as follows.
3. In case of re-servicingthe same gel, the "gear for servicing" may has been taken off because ithas been used.
The "gear for servicing" must be stored.
1. Remove the gear provided with mechanism cover
as shown below. 2. Insertthe hexagonal screwdriver (2 mm) into the
gear and then project the tip of screwdriver for
1~2mm in length.
~t-
Gear ~.
nHexagonal screwdnver
VIPart No. : SZZP11 0.1C]
Mechanism caver -1~
1-2mm
c=:
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"ATTENTION SERVICER"
2.
Some chassis components may have sharp edges.
Be careful when disassembling and servicing.
1. This section describes procedures for checking the operation of the majar printed circuit boards and replac-
ing the main components.
For reassembly alter operation checks or replacement, reverse the respective procedures.
Special reassembly procedures are described only when required.
3. Select items from the following index when checks or replacement are required.
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Contents
eDisassemblyandassemblymain unit
1. Checking of the Main, Panel, Deck and Power P.C.B.
Main component Replacement Procedures
1. Replacementof the Traverse Deck.
2. Replacement of the PowerAmplifier IC.
eDisassemblyand assemblyof theTraverseUnit
eDisassemblyandassemblyof the DiscTray
Warning:
This product uses a laser diode. Refer to caution statement Precaution of Laser Diode.
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SC-HM900 I
8.1 Disassembly and assembly main unit
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Step 1 Remove 4 screws each side and remove
the Top Gabinet.
E)x 4
Step 3 Pul!out the CD tray as shown and remove
the CD lid. Push back the CD tray after the
CD lid has been removed.
Step 2 To open the CD tray, releasethe le-
ver as shown.
~~
E)x 4
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Step 4 Remove the screws.
G)
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0x 16 .......
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