Panasonic SAHT730 - DVD THEATER RECEIVER, SC-HT730, SC-HT930, SB-FS930, SB-WA930 Technical Manual

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Technical Guide

5-DVD Changer Home Theater System

SC-HT730, SC-HT930 Models

Practical Servicing of

B02

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Prepared by

Herb Chin, & Joe Blanks

Panasonic Services Company

National Training

Panasonic is a registered trademark of Panasonic North America "HDMI, the HDMI logo and High-Definition Multimedia Interface are trademarks or registered trademarks of HDMI Licensing LLC."

BBE, the BBE logo, Sonic Maximizer and High Definition Sound are registered trademarks or trademarks of BBE Sound, Inc. Photoshop is a registered trademark of Adobe Systems Incorporated in the United States or other countries. Dolby is a registered trademark of Dolby Laboratories.

istered trademark of Digital Theater Systems Corporation.

Warning

This service information is designed for experienced repair technicians only and is not designed for use by the general public. It does not contain warnings or cautions to advise non-technical individuals of potential dangers in attempting to service a product. Products powered by electricity should be serviced or repaired only by experienced professional technicians. Any attempt to service or repair the product or products dealt with in this service information by anyone else could result in serious injury or death.

SA-HT730 / SAHT930

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Table of Contents

OBJECTIVE............................................................................................................................. 4

I NO START-UP AND DVD TRANSPORT PROBLEMS................................................. 5

1. POWER-ON START-UP SEQUENCE – WHERE IS THE PROBLEM?........................................... 5

2. SENSORS, BELTS, AND MOTOR LOCATION ............................................................................ 6

3. SIMULATED FAILURE SYMPTOMS – QUICK FIXES................................................................. 7

4. TRAY REMOVAL FOR SENSORS, BELTS, & DIAGNOSTIC ACCESS......................................... 8

5. TRAY INSTALLATION (AFTER REPAIRS)................................................................................ 9

6. SENSOR TESTING ............................................................................................................... 10

Testing the Tray Loading Motor and Related Sensors .................................................... 10

Testing the Tray Rotation Motor and Related Sensors.................................................... 11

II SHUTDOWN PROBLEM................................................................................................ 12

PROTECTION CONCEPT – ALL THE SHUTDOWN POSSIBILITIES................................................12

Overall Repair Strategy ................................................................................................... 12

CONTROL UNIT REPAIR (SA-HT730 / SA-HT930) STRATEGY ............................................. 13

Control unit repair Procedure......................................................................................... 14

Jumper Paths to System Control IC2018 for Shutdown Problems.................................. 15

Control Unit Protection Concept.....................................................................................16

SUBWOOFER UNIT REPAIR (SB-WA730 / SA-WA930)........................................................17

Subwoofer Repair Strategy – Start by isolaating the problem......................................... 17

Subwoofer Repair Procedure........................................................................................... 18

Subwoofer Disassembly ................................................................................................... 20

Subwoofer Test / Operating Position............................................................................... 21

III NO AUDIO PROBLEMS ...............................................................................................22

How to trace down no audio (one or more channels)...................................................... 22

SA-HT730 / SAHT930

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Objective

This technical guide was prepared with the following objectives in mind:

• Provide the servicer with a brief overview of the concepts of operation for new circuits employed in this line of models.

• Provide drawings with emphasis on signal path to simplify the task of signal tracing and to locate the cause of a defect.

• Furnish troubleshooting procedures that contribute to a speedier repair of the product.

• Provide examples of typical problems that may have occurred in similar types of circuits.

SA-HT730 / SAHT930

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I No Start-Up and DVD Transport Problems

Model: SA-HT730 / HT930. Since this unit normally starts in DVD mode, start-up symptoms are often caused by DVD transport problems – A failure in the DVD transport stops the start up. Servicing the DVD section is divided into 6 groups (pick and choose what you need):

1. Power-On Sequence 4. Tray Removal for Diagnostic Access

2. Sensors, Belts and Motor Location 5. Tray Installation (after Repairs)

3. Simulated Sensor Failure Symptoms 6. Sensor testing

Start with the power-on sequence. The power-on sequence is important for identifying the section that does not start. Compare the sequence in the defective unit to the correct sequence listed below in table 1. The step where the unit stops working is where the problem is (or in the step just before). Testing the sensors is the next diagnostic step (section 6) if the transport works but behaves out of sequence. Section 2 locates the sensors. However access to the sensors for testing is tricky but the trick is revealed in section 4 - tray removal. After repairs, section 5 shows how to align the gears for reassembly.

1. Power-On Start-Up Sequence – Where is the problem?

After AC is disconnected, the unit always powers on into the DVD operation mode.

SA-HT730 / HT930 Power ON sequence

Step Time Operation Display Proof

1. 0 AC input. Unit off.

2. 0 Press Power button Disc # 1-5 light in sequence.

3. 1 sec “Hello”

4. 4 sec Micro IC8001 controls laser

assembly via cable to CN2004. See table 2.

5. 5 sec Loading motor moves the

Tray in (if S9001 is not open) and into the disc unchucked position using two loading sensors. No movement will occur if the transport is already in this tray in unchucked position.

6. 8

sec.

7. 17 Tray motor stops at original

1. Disc Tray motor rotates. Slow rotation is first.

2. Detection of discs on platter / tray.

disc slot.

None

appears “INIT” appears

“Please Wait”

“ No Disc”

Table 1

Red light over pwr button (standby).

All disc numbers 1-5 light. Disc proof sequence is followed *

see table 2. Two loading sensors are used:

1. S9001 = contacts open / tray closed. Contacts are open if the Tray is in.

2. Q9001 at CN2011/6 = 0Vdc = non-clamped position (tray rotation is possible when the disc assembly is unclamped.)

1. S9102 detects tray motor gear rotation.

2. Q9103 detects each disc when the disc blocks the Q9103 light.

S9101 also detects tray rot. position.

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* Disc Proof Sequence (no disc loaded)

a) Sled moves to home position (at

center).

b) Sled moves out to DVD TOC

location. c) Laser ON. h) Focus search 3X. 3. Volts missing d) Focus search 3X. (spins if disc is

found) e) Sled moves to home position (at

center).

f) Sled moves out to DVD TOC

location.

g) Laser ON. 2. Mechanical

i) Sled moves to home position 4. Traverse j) Sled moves out to initial position. 5. IC8251 –

Table 2

Checkout

Failure

1. Ribbon cable

binding

Motor motor drive

2. Sensors, belts, and motor location

Items in dotted lines are under the tray. Since many parts are under the tray, the tray must be slid out to test the parts. This is easier than it looks. Use disassembly section 4 to access the parts shown below.

SA-HT730 / SAHT930

Part numbers Tray Belt = RDV0073 Loading Belt = RDV0073 Loading Motor = REM0112 Tray Motor = same as above

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3. Simulated Failure Symptoms – quick fixes

Although sensor failures cause the following symptoms listed in table 3, the more common failure is an internally broken ribbon cable that carries the sensor signal to the microprocessor.

To determine which is at fault, begin testing using figures 4 and 5 or order the cable with the corresponding sensor. For example the motors (#6 & #7 in table 3) and S9001 (#4) can be quickly checked with an ohmmeter at the CN2010/2011 cable end (see figures 4 or 5). If the part tests bad bypass the cable and recheck the part right at the part’s terminal.

CN2010 ribbon cable p/n = REZ1484 (11 pins) CN2011 ribbon cable p/n = REZ1483 (10 pins)

Simulated Failures

Sensor Cable Symptom Comments

1. Disc Det Q9103 open

2. Tray rotation Q9102 open.

3. Tray position Q9101 open.

4. Main gear position Q9001 open.

5. Tray out switch S9001 open.

6. Tray Loading Motor CN2011 Front panel display = “Please Wait” or

7. Tray Rotation Motor CN2010 Front panel display = “Please Wait”

CN2010 No disc detected (no PB possible). CN2010 Tray motor rotates back & forth for ¼ rotation then

shuts down. H01 error code shown.

CN2010 Slow continuous CCW rotation of the tray. “INIT”

appears and no buttons work except power.

CN2011 Tray moves out and spins, then the tray moves in.

and the mech clamps & then unclamps. Repeats.

CN2011 Normal start up. Pressing the open tray button

permits the tray to open but it closes automatically.

“Open/Close”

Table 3

Unit shuts down. Unit does not shutdown. Unit does not shutdown. Tray will not stay open.

Motor = 14

ohms

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4. Tray Removal for Sensors, Belts, & Diagnostic Access

Removing the tray to access the sensors and motor first requires removing the tray trim, and then the front panel (not shown) before the tray assembly will come out. Follow figure 2 for easy tray removal. CAUTION – metal chassis edges are sharp.

Quick Procedure:

1. Rotate the white Close Lock Gear / lever CW (clockwise) within the turntable platter to unlock the tray. Pull the tray forward (towards yourself) until it stops.

2. From the bottom of the black tray, remove the front silver trim piece (not shown).

3. Unplug the two front panel cables (CN2008 & CN2009) and remove the front panel (not shown).

4. On the main board, remove the cable (CN2010) attached to the tray.

5. Move the rear white lever counter-clockwise (CCW) as shown in figure 2 and at the same time

6. Release the two parallel tray stops (a and b) by pressing the larger tab (closest to you) inward toward the center of the tray (figure 2).

7. Slide the tray out towards yourself to expose the sensors, motors, and belt.

5. 6b

CN2010

Contacts = rear

CN2008

Contacts = left

CN2009

Contacts = rear

Figure 2 – Tray removal revealed

2. Remove trim from the bottom.

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5. Tray installation (after repairs)

Refer to figure 3. Positioning the main black gear and a white gear is all that is required to slide the tray back in.

Procedure:

1. Main black gear – Rotate the gear so that its hole is at the 5 o’clock position and its line across the gear is horizontal as shown in figure 3. In this gear position, the laser assembly is clamped.

2. White gear – Rotate the (now free moving) left white gear so that its top molded in lines point towards the rear as shown.

3. Without crushing the tray’s ribbon cable, slide the tray halfway into the mechanism.

4. Plug in the tray’s ribbon cable into CN2010. The cable’s contacts face rearward.

5. Push the tray all the way in.

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6. Sensor testing

These 7 electrical parts could cause transport problems but so can a broken mechanical part. Test all 5 sensors and 2 motors as a group once the tray is removed. If the parts test OK, the problem is mechanical or a ribbon cable is bad.

Testing the Tray Loading Motor and Related Sensors

With the tray removed (section 4), install the front panel to test the tray loading operation. Plug in front panel ribbon cables CN2008 and CN2009.

Testing Parts 1/2

Part Setup Do / Watch Proof the part is good

1. Tray in – out loading motor

2. Tray out sw. S9001

3. Main gear position Q9001

1. Rotate the main gear to the disc clamped position.

2. Press power on. Unplug the unit from AC power.

Press the poweron button.

After laser focus searches (“INIT”), the loading motor turns to drive the transport to the non-clamped position (“WAIT”). The unit will then shut down (“H01 error”).

Measure the resistance between CN2011 / pin 1 and pin 2.

Rotate the main gear to the position shown in figure 4 inset so that you can see the sensor in the cutout. Rocking the gear changes Q9001’s logic state.

Table 4

Motor must turn belt and the main black gear into the disc unclamped position. Motor resistance = 14 ohms. Motor volts = 8Vdc. Between CN2011/pins 8 & 10. The switch is normally open but shorted when pressed (simulates tray out). The voltage at CN2011/pin 6 will change from 0.1Vdc to

4.6Vdc as you rotate the main gear to block Q9001’s light.

Q9001 Main gear position sensor test CN2011 / pin 6 =

0.1V – 4.6Vdc as gear is rotated

Main gear position

sensor S9001

Figure 4 – Loading (Tray In – Out) Motor Circuit

SA-HT730 / SAHT930

S9001 tray in / out test Shorted - Tray out Open – Tray in [Front panel displays the words “Open” or “Close”.]

Inset

Main black gear position for

Q9001 sensor inspection

Cutout shows Q9001

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Testing the Tray Rotation Motor and Related Sensors

1. With the tray removed, install the front panel to begin the remaining tests.

2. Place the plastic tray on top of the unit between the laser block and front panel.

3. Plug the tray ribbon cable into CN2010 for testing.

Testing Parts 2/2

Part Setup Do / Watch Proof the part is good

4. Tray rotation motor

5. Tray rotation sensor S9102

6. Tray position sensor Q9101

7. Disc presence detector Q9103

Press the power on button.

Press the power

on button.

Press the power on button.

Tray motor should turn 8 seconds after the power button is pressed. Rotate the tray motor gear by hand.

Before the unit shuts down, rotate the tray past the disc center position at the laser assembly. Move the tray past the disc sensor.

Table 5

To CN2010

3.6Vdc

Power to tray motor: Pin 11 = gnd. Pin 10 will go from 0 – 2V – 5.6Vdc. At CN2010/pin 4: Voltage changes from

0.1Vdc to 4.6Vdc as the tray gear is turned. Volts at CN2010/pin 2:

0.15Vdc = Tray centered for disc playback. 5Vdc. = Tray in transit. At CN2010/pin 6:

0.3Vdc = light reflected back from top plate. 5Vdc = light blocked

Motor: pin 11 = gnd. Pin 10 = 0V, 2V, 5.6V

CN2010/Pin 6:

5.0V = Disc

0.3V = No Disc

Pin 4: motor rot.

0.1V to 4.6Vdc

Figure 5 – Tray Rotation circuit

SA-HT730 / SAHT930

CN2010/Pin 2:

0.15 = disc centered 5Vdc = tray bet discs.

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II Shutdown Problem

Protection Concept – all the shutdown possibilities

Refer to figure 6. The models SCHT730 and SCHT930 are both 2-piece units (with speakers). The SA-HT930 / SA-HT730 control piece (figure 6, right) has no AC input. The control unit power comes from the SB-WA 30 “Subwoofer” piece through a 25 pin umbilical cable (not shown). The subwoofer (left) houses the power output amplifier for all 6 channels and delivers protection information to the microprocessor (Syscon IC2018) in the control unit.

Figure 6 -

Overall Repair Strategy

Shutdown protection can be started in either the control unit (SA-HT730/HT930) or the subwoofer (SB-WA730/WA930). Start the repair with either unit to first determine which piece houses the problem, and then follow the individual Repair Strategy procedure to isolate the problem.

Control Unit - In the control unit, most parts are under the board. Access to test areas for diagnosis is overcome by using the jumper wires on the top as test points. Since test point jumpers are used, additional diagrams and pictures are used to quickly locate the jumpers. The repair flow information is shown in figure 7. Control unit repair starts on page 13.

Subwoofer Unit – All parts are accessible once the electronics is pulled from the subwoofer speaker cabinet. Unscrewing the board from the metal frame and rotating it 90 degrees permits operation if a ground wire is added (service position). Subwoofer unit repair starts on page 17.

SA-HT730 / SAHT930

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Figure 7 – Repair Information

Control Unit Repair (SA-HT730 / SA-HT930) Strategy

SC-HT730 / SC-HT930 Repair Strategy for a shutdown (F61) symptom: These two units differ in power output so the ‘HT930 has an additional board in the subwoofer. Troubleshooting of the control unit is almost identical for both models. Shutdown can be either in the control unit or subwoofer. Refer to figure 8. In the control unit, diagnostic troubleshooting is quickly done from the top of the main board by cutting jumper wires to isolate the problem. Cutting specific jumpers on the board to stop the shutdown problem from reaching Micro IC2018 is a fast way to determine if the problem is in the subwoofer or the control

unit. Use figure 9 to cut additional jumper wires to isolate the problem to an exact circuit. Thereafter, repairs are done from the bottom where the parts are located.

SA-HT730 / SAHT930

Figure 8 – Cut Jumper wire Concept

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Control unit repair Procedure

To perform the following steps, you need to locate the jumper wires and identify which jumpers carry what shutdown signals to the IC2018 microprocessor (using figure 9). The purpose of the jumpers is found in the concept diagram figure 10. Procedure:

1. First prove the problem is in the control unit by cutting the W2344 jumper on the top of the board (at location grid K7). Measure the voltage at W2156 / G8 at power on. This cut disconnects most of the control unit’s protection into micro IC2018.

• If the 9Vdc is present before shutdown, the problem is in the subwoofer assembly and not in the control unit. Reconnect the jumper and go to the repair information on the subwoofer (page 12).

• If the 9Vdc is present, and the unit does not shutdown the problem is in the control unit. Shut off the unit and proceed to step 2.

• If the 9Vdc is absent, the problem is in the control unit. Refer to figures 9 and

10. Either the M9V source (Q2803) is missing or the 9Vdc is loaded down (reduced).

Cut jumpers W2413 and W2154 one at a time to determine which load causes the reduced or missing voltage. If cutting both jumpers does not restore the missing 9V, the M+9V source is bad.

2. If the unit does not shutdown because you have compromised the protection circuit (e.g. cut W2344), only keep the unit on to measure a test voltage. Monitor the various voltages at these jumpers to determine which is incorrect: [The jumper’s grid location follows the “W” jumper number.]

 W2550 / M7 = SW 5Vdc  W2417 / K8 = + 7Vdc  W2340 / I7 = - 7Vdc  W2235 / K9 = 0Vdc

Inv Q2818

 W2427 / J8 = 9Vdc

3. Except for the K9 (0V) measurement, if any of the voltages listed above is

missing, cut the (load) jumper and measure each of its ends. If the voltage is now present at one end after the cut, its load is shorted. Trace down and troubleshoot the Use the “Protect Paths to Micro IC2018” diagram (figure 9) to make sure that the jumper is the load jumper that bridges the load and the source voltage before cutting.

IC2018 Micro

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Jumper Paths to System Control IC2018 for Shutdown Problems

C2018

SYS 6 from JK2000

/ PIN 4 Subwoofer

W2145 /M6

W2541 /K6

Pin 2 of JK2000

From SUB W

M9/T9 SOURCE

D2001

Q2803 /C

W2615 /H8

W2154 / I8

W2158 /H7

W2705 / I6

CN2004

PINS 5,7

Stby 6V

Pull up resistor

TP Jumpers (eg. W____ ) are accessible from the top of the board

W2550 /M7

CN2009 /Pin 18

W2118 /M7

W2549 /M7

W2515 /L4

)

R2069

CUT*

SYSTEM

CONTROL

D2850

W2156

/G8

R2707 R2708

CUT*

W2413 /E8

TUNER

DC Det

W2344 /K7

C+9

source

Q2811 /C

SW5

source

Q2813 /E

CN2009

PIN2

LED’S

MOTOR DRIVES

IC2007/pin 7(Tray)

IC2008/pin7(Loading

SW5 / +7

D2851

D2852

W2427 /J8

SW5V load

Q2818

W2235 /K9

Q2801 /C

OCP

CN2010/pin8

PHOTO

INTERRUPTER

Q9103/pin1

W2855 / H6

W2582

/ K8

W2231 /K7

-7V load

W2417 /I7

W2340 /I7

W2854 /H6

+7V load

+7 source Q2814 /E

-7 source Q2807/E

SA-HT730 / SAHT930

Figure 9 – Jumper Paths & Location

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Control Unit Protection Concept

Figure 10 – Control Unit Shutdown Simplified Schematic

SA-HT730 / SAHT930

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Subwoofer Unit Repair (SB-WA730 / SA-WA930)

Overview - Refer to figure 11. The SC-HT930 consists of a Subwoofer and Control unit. The units are connected by a 25 pin round umbilical cord that carries power from the Subwoofer to the control unit and audio from the control unit back to the subwoofer. When connected together and plugged in to AC, the Subwoofer provides standby (SYS6V) voltage to the micro in the control unit. The SC-HT730 model is similar but has less front channel wattage. That model does not have a Subwoofer front Amp Board. Its front channel power amplifier is part of IC501 in the subwoofer’s Power Board.

Figure 11 -

Protection - Refer to figure 11. The protection monitoring circuitry in both of the subwoofer (left) and control unit (right) feed the microprocessor IC2018 in the control unit. If shutdown is triggered, the micro via the 25 pin umbilical cable opens the subwoofer AC relay power relay, shutting off the power for both the control & subwoofer [but standby voltage (SYS 6V) is still present]. Error code F61 may be displayed just before power is lost. In the subwoofer, the lines monitored for shutdown are:

• Speaker Balance – All 6 channels to the speaker must average 0Vdc +0.6Vdc with or without audio or the unit will shut down.

• + 9Vdc balance – Both the positive and negative 9V power supplies must be within 1.2V of each other or the unit will shut down.

• + 9Vdc loss – Missing 9V or excessive 9V load that brings the 9V line below 5Vdc will shut down the unit.

Subwoofer Repair Strategy – Start by isolating the problem

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Follow this procedure to determine if the Subwoofer causes shut down: Refer to the subwoofer protection simplified troubleshooting circuit, in figure 12. Disassembly and service positions are shown in figures 13 and 14.

3. Do not connect the Control unit to the Subwoofer. On the larger power board of the subwoofer, tack a 10k ohm test resistor across D508 to serve as a temporary “DC Det” pull-up resistor so that the subwoofer can be tested alone.

4. Jump the contacts of the AC relay RLY501.

5. While monitoring the unbanded anode end of D508 with your DC voltmeter, momentarily plug the subwoofer into AC.

6. If the voltage remains at 0Vdc, unplug the AC immediately. The problem is in the subwoofer. See subwoofer repair below.

7. If the voltage rises to 7-9Vdc, the problem is in the Control unit, not this subwoofer. Disconnect the test resistor and close the subwoofer.

Subwoofer Repair Procedure

1. Refer to figure 12. To supply pull-up voltage, either leave the 10k ohm test resistor across D508 or plug in the control unit, but Do not do both.

2. On the SB-WA930 Subwoofer, remove the Front Amp board. See subwoofer disassembly diagrams figures 13 & 14.

3. If RLY501 contacts are shorted, momentarily plug the subwoofer into AC while monitoring the unbanded anode end of D508 with your DC voltmeter. If the control unit is connected, press its power-on button while measuring the D508/A voltage.

• Voltage remains at 0Vdc - the problem is on the subwoofer’s power amp

board. Remove Q501/Q502, Q559, and Q556/Q557 one group at a time to determine which group permits D508/Anode voltage to rise to 5-9V when plugged in momentarily. If removing a group of transistors causes D508/A voltage to rise, the feed for those transistors is at fault. E.g. If Q501/2 was removed, and the voltage came up to 5-9V, suspect IC501 and the transistors removed (Q501 & Q502).

• Voltage rises to 5-9Vdc (normal voltage): SB-WA930 - the problem is in the

Amp board that was unplugged or the + unbalanced (+V not = -V). Check for open foils to connector H601 and replace IC601 on the board. SB-WA730 – The problem is not in the subwoofer. Check the control unit.

4. Remove the 10k ohm test resistor across D508 to prevent micro damage.

supply voltage from T501 (H601) is

SA-HT730 / SAHT930

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Figure 12 – Subwoofer Power On / Protection Circuit

SA-HT730 / SAHT930

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Subwoofer Disassembly

SA-HT730 / SAHT930

Figure 13 – Subwoofer Disassembly

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Subwoofer Test / Operating Position

After removing the boards, the grounds must be reconnected for operation and testing. Procedure:

1. Remove screws to free the bottom frame from the heat sink and PC boards.

2. Rotate the assembly and rest the heat sink on the bottom frame as shown.

3. Connect the ground screw terminal to the heat sink as shown in figure 14.

4. Install the umbilical (system) cable if you are troubleshooting with the control

unit, otherwise you will tack in the 10k ohm test resistor to troubleshoot the subwoofer independently (Subwoofer isolation procedure on page 15).

5. The subwoofer assembly is now operational and in a serviceable position.

Ground screw terminal

Front Bd. SBWA930 only

Figure 14 – Subwoofer Operational Service Position – SB-WA930 shown

SA-HT730 / SAHT930

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III “No Audio” Problems

A loss of audio in one or more channels can either be caused by a break in the signal flow or a line being muted. Use the following two diagrams to see the audio signal flow, the mute locations, and the location of accessible capacitors in the signal path for signal tracing.

How to trace down no audio (one or more channels)

Once an audio tone is generated (A) it can be followed through the unit (B).

A- Generating test audio to the speakers: Refer to figure 15.

Notice: When a headphone is plugged in, all the audio to the subwoofer amplifier is

muted so there is no sound from any speaker (only to the headphones).

1. TV, VCR, and FM – These stereo audio inputs produce audio from the front

and subwoofer speakers only unless the remote’s “Super Srnd” button is pressed. Then “S.SRND” appears on the front panel and all 6 channels output audio.

2. DVD - When playing a DVD movie with DTS or Dolby Digital (“SFC” will light in

the display and) all 6-channels will work. Older stereo-only movies (no SFC light) will only deliver 2-channel stereo sound. When the remote’s “Super Srnd” is pressed, the front panel display shows “Error”.

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3. Internal test tone - An alternative to input a signal to test the amplifier is to use

the internal speaker level test mode. Once in this test mode, IC2011 generates a fixed level signal to each speaker, one at a time except the subwoofer. The test tone lasts for approx half second at each speaker and repeats. As feedback, the display shows which channel is test active.

Test Tone generating procedure: a) Turn the unit on. b) Press the front panel or remote input selector to select DVD / CD (front

panel display).

c) On the remote top opaque buttons, press DVD (so the remote buttons are

for DVD mode.

d) On the remote, press both the SHIFT and TEST buttons. The front panel

display will show the speakers that are producing the test tone.

e) Stop the test tone sequence – press ENTER or both SHIFT & TEST

buttons.

B Tracing the audio

• Audio output IC2011 can be traced by following the audio path through coupling capacitors at the top of the main board.

• Use figure 15 to identify the signal path and figure 16 to locate the capacitors in the path. Follow the signal from capacitor to capacitor with a scope to determine where the signal is lost.

Figure 16

SA-HT730 / SAHT930