Technical Guide For 2008-9 models: 6 Home Theater …diagramasde.com/diagramas/otros2/PANASONIC...

Models:SA-PT660SA-PT760SA-PT960SA-PT1060SH-FX67, 85

OutlineWirelessMechPwr SupplyProtectionAudio

Home Theater Products Repair

Panasonic Service and Technology Company

SA-PT660 SA-PT760 / 954 / 956SA-PT960SH-FX65, 67, FX85 (wireless)

For 2008-9 models:Technical Guide

National TrainingSample Model SC-PT760 Home Theater System

ContentsHints / Layout / Reset 4Wireless Section 8Power On Sequence 14

5 Disc Mechanism (CR-14)o Operation 15o Alignment 16o Troubleshooting 21o Laser replacement 25

Power Supply, 31Protection Troubleshooting (F61 or F76 Error Code) 34No Audio (main unit) 39

SA- PT760

Herb Chin



Panasonic Service and Technology Company

Produced byPanasonic Services and Technology Company

National Training DepartmentSecaucus, NJ

WarningThis 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.

Copyright © 2008 by Panasonic Services CompanyAll rights reserved. Unauthorized copying and distribution is a violation of law

Slide # 3




Table of ContentsElectronics –Layouts / Hints Hints – p/n, New codes, Tests, Reset 4Layout w test points and PS voltages 5Wireless

SH-FX65/66 Rear Receiver Setup 8Wireless Troubleshooting Plan 9Testing & Paring Trans & Rec 10Transmitter / Receiver Repair Info 11

Power ON Power On Sequence 14

Mechanism – stacked 5 Disc model CR-14

Operation 15Alignment 16Troubleshooting 21Laser Replacement (removal & install) 25

Power SupplyPS Block with isolation strategy 31PS Circuit with ref voltages 32

ProtectionProtection Concept (F61 & F76 codes) 34Protection Circuitry 35Protection Repair Procedure 36

AudioConcept 39Speaker Output Waveform 40Sample Problems & Repair Methods 41

SA-PT660

SA-PT760

SA-PT960

T

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center

center SW

T

R

center

SW

Slide # 4



Hints – I Common P/N, II Missing error codes, III Unplugged cable symptoms, IV Reset

I Popular Part Numbers

Description P/N Note

Remote SA-PT760, PT960

N2QAyb 000 214

Remote SA-PT660 N2QAyb 000 210

Fan L6FAJCCH 0007

Output ICs C1bA 00000 487

Transmit Card Repx 0644b

Receiver card Repx 0645b

CR-14 Mechanism RD-DDC026-S Exch

Traverse / Laser Assem RR-DDtx002-V

II Error Codes not in the Service Manual:Changer Error – appears when a button is pressed and the mechanism is not responding. Go to the mechanism troubleshooting of this book to determine if it is mechanical.

Sum Error – Incorrect communications with DVD board micro. Transport is dead, DVD can not be selected. Replace 50 pin ribbon cable or DVD bd.

F897 – Play the recovery disc and reset the unit. (see IV at left)

III Troubleshooting by cable RemovalCable

RemovedDisplay Symptom

1 Large 50 pin DVD cable CN2001 off

Hello, Aux (last input),

Close, “change

error”

Fan on, No AM/FM mode, No audio. Unit remains on.Vol level # changes w knob but no audio.

2 2 rear mech cables off (fp8531,fp8251)

Hello, Din. Fan on, Mech motor buzzes, display skips DVD when press Sel button, No audio.

3 Main Bd. CN2007 off

None CN2007 is only for the display. No display. Unit works OK otherwise.

4 PS Bd / mech CN2011 off

Hello, Change, Open.

Fan on, locked on last input mode used but that audio works fine with volume control.

IV Reset after DVD Board replacement1. After replacing the DVD board Play recovery disc

(p/n = RFKZD 03r005) containing firmware + update. Select yes or no for update.

2. Reset –1. Select DVD mode & wait for “1 No Disc” display.2. Press >10 (remote) and (panel). = Stop.3. Until the display = “INIT”.4. While still pressing STOP , also press the remote

OK button until the word “RESET” appears.5. Power off the unit and unplug for 1 min.

Slide # 5



PT760 Layout 1 – Top Level

Slide # 6



PT760 Layout – Bottom Level

Slide # 7












SA-PT660

SA-PT760

SA-PT960

T

RSW

center

center SW

T

R

center

SW

Slide # 8



Home Theater Wireless ProductsPanasonic ModelSA-PT660 – no wireless spks.

(optional FX67 or / & FX85)SA-PT760 – wireless rear spks.SA-PT960 – wireless rear spks + more pwr

SH-FX65/67max range = 49’

ID set button

(back)

Receiver

Transmitter card

Wireless rear receiver

Optional for the ‘PT660

Transmitter card – REPX 0644b

Receiver card - REPX 0645b

Need a manual for the wireless portions of the above units? Try a model below.

SH-FX65 – takes spk wires.

SH-FX67 – takes spk plug.

Slide # 9



SA-PT760 Wireless Troubleshooting Plan

Wireless rear does not work – W1 or W2 display icons do blink at power on.

Wireless rear does not work – W1 or W2 display icons do NOT blink at power on.

1. RF connection has not been made. Go to slide 6 to pair the transmitter and receiver. Steps 1-6.

2. Go to slide 8 to troubleshoot the receiver. Make sure there is standby voltage input the receiver and the pair button is working (pin 9 grounds when the button is pressed.

3. Go to slide 7 to check the transmitter card Sw +5V voltage at the main board (CN2003) or at the card socket itself CN6301).

1. The RF connection is OK. No audio is the problem. Replace the transmitter card if hot (damaged when plugged in while the unit was powered on).

2. Go to slide 6 and follow steps 7 to turn on “S Music” mode (surround music). This makes the rear surround speaker sound the same as main L & R.

3. Input an audio source (play some music).

4. Disconnect the speakers and turn the volume control to max (level number 50 is displayed).

5. Go to slide 8. Check for audio at the receiver card CN1100/pins 2 & 4.

6. If there was no audio present at CN1100 (receiver), Go to slide 7. Check for audio at the transmitter socket CN6301/pins 10 & 12.

Slide # 10



Wireless Information – RF Pairing / Matching T & R

2. Transmitter card

5. ID Set button

ID Set

3. Press panel FF & 3 buttons

RF Pairing1. Proximity – Bring the wireless receiver to the transmitter.

2. Power ON – Plug the transmitter card in. Turn everything on and press the selector button for DVD mode. (Do not plug the card in with the unit on. A damaged card will get hot.)

3. Setup – While the W1 / W2 icon is blinking in the unit’s display, hold down the front panel FF button and the remote’s “3” Button.

4. Indicators – a) W1 / W2 will blink on the main unit’s display if the transmitter card is inserted. b) “P” icon will be displayed when the pairing process is started.

5. Mating – While the “P” is present, press the rear receiver recessed “ID Set” button.

6. Indicator – The W1 / W2 will stop blinking proving an RF match has been made.

7. Audio Test – Repeatedly press the remote’s SOUND button until the

panel displays “S.Music”. Then press the arrow button to turn ON “S.

Music”. The rear speakers will have the same music as the front L & R.

8. W1 / W2 still blinking? – Use the troubleshooting info in the next pages.

On

7. Rear Audio Test

1. H. Bass2. R.C. FCS3. SRD Enh(ance)4. S.Music

Slide # 11



Wireless - Troubleshooting Information ½ - Transmitter partUse this diagram to:

Prove that the T card is recognized (CN2003/pin 11).Power is getting to the T card (CN2003/pin 9).Audio is getting to the T card (CN2003/ pin 2-8).

Notes:1. Measure the voltages at the CN2003 main board with the Transmitter card / Bd. plugged in.2. Channel 2 audio is present with a surround sound DVD or if the S Music is turned ON. See the previous slide, step 7 for access S Music.3. Channel 1 audio is only present when its 2nd room accessory transmitter card is plugged in. Otherwise channel 1 is muted.4. Data is only present when the T card is in.

Rear of Main Unit

When the T card is inserted, the micro blinks a W1 icon



Slide # 12



Wireless - Troubleshooting Information 2/2 – Receiver part

Use this diagram to:

Receiver card is getting power (CN1100/pin 5).Receiver card is outputting Audio (CN1100/ pin 2).Receiver card is not muting the audio (CN1100/ pin 10).



SH-FX67 receiver / amp

Slide # 13






Power ONPower On Sequence 14






SA-PT660

SA-PT760

SA-PT960

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Slide # 14



1. Plug In, Press Power On2. Fan turns on - starts noisy (high speed)3. Hello is displayed4. Last Mode used is displayed

(DVD, Aux, D-in, Am, FM, or IPod)

Unit Operation - Plug in, Power On Sequence

5. Use the panel “Select” button to change modes or the < or > buttons to change stations.

6. Tray 1 status is displayed (disc tracks or time or No disc)

Trays stocked

laser

Tray 1

Tray out position

5. Micro checks “Top” & “Home” mech switches to ID tray 1 (SW3 & Q3 = 0Vdc = tray 1 loaded in the laser).

6. If tray 1 is not in the laser compartment (default), the mech will load tray 1 in:

• Not tray 1 moves to stock (center) position. (Q1 UD sensor = 0Vdc to stop rear traverse motor)

• Elevator moves laser assembly up to tray 1 level (SW 3 = 0Vdc at top level to stop the stock/elevator motor @ tray 1)

• Tray 1 is pulled into the laser assembly

• Mech clamps the disc

7. With Tray 1 in the laser compartment, Disc Detection occurs – Laser moves away from home, laser on, focus searches. Disc spins if a disc is found.

8. Tray 1 status (contents if any) is displayed.

DVD ModeAux, D-in, Am, FM, or IPod Mode

Fan

SA-PT760mech

Top view

Tray release

mech

Slide # 15



5 Disc Mechanism - Operation

Default position = Tray 1 is loaded into the laser assembly at plug-in, power-on when the DVD function is selected. The remaining 4 trays are in the middle “stock” area.

Tray 5 selection – (button 5 is pressed)

a) Press 5 button – Display = “Disc 5”b) Laser unclamps and the tray returns to middle stock location (TRV motor). c) Display = “Change”d) Laser assembly lowers to tray 5 location (Stocker motor). e) TRV motor pulls tray 5 into the laser assembly. f) TRV motor clamps the disc if any.

g) TRV motor moves the sled away from home position to begin disc readout for play.

All Trays out – (Close / Open button is pressed)

a) Laser drops down (unclamps) and tray returns to middle stock location (TRV motor).b) Stocker motor continues to turn to internally catch all 5 gears of the #328 “OC” gear. When the last gear is caught, all the trays are moved to the end of the stock area almost out of the mechanism (for disc insertion)

laser

Stock location

Trays 2-5rear Side View

Slide # 16



5 Disc Mechanism - Concept & Transfer Alignment 1/4

Figure 1b – mech components

Operational Concept:

There are 2 motors and 8 sensors in the CR-14 mech.I. The traverse motor moves:

• Laser back & forth • Clamps disc• Pulls trays into the laser assembly

II. The stocker motor moves • Tray(s) between the middle stocker

area and out of the assembly (for disc insertion)

• Traverse / laser platform up/dwn,

III. Trays moved from the stock area must be transferred to the laser area.

1) Tray transfer is made after the traverse assembly elevators to the desired tray level. The following occurs in the rear traverse assembly:

2) The traverse motor uses arms to pull the tray into gear #331. Pictures in the fourth slide 4/4.

3) SW4 opens (fp 8251) to tell the micro the tray is in.4) The traverse motor continues to turn, bringing the tray

in, then clamps the disc5) SW5 opens (fp 8251) at clamp end and sled moves

away from home.6) The sled moves the laser to the approx TOC disc

area & stops. The laser comes on, lens focus searches and if a disc is found, spins it.

7) SW4 and SW5 are both inside the Traverse assembly.

laser

Stock area

Trays 2-5rear

Figure 1a – Default position side view

rear

Traverse assembly p/n = RD-DDtx002-V

Mechp/n = RD-ddc 026-S

laser

Tray 1

Stock motor

traverse motor

Top view

Slide # 17



5 Disc Mechanism - Assembly Transfer Alignment – Trays Out 2/4

Preparing the Traverse unit for docking:

1. Trays Out (laser down)

2. Rotate the black gears so the white slider and laser are forward, as shown.

Next page is a close up picture.

Rear

Figure 2

Slide # 18



5 Disc Mechanism Assembly Transfer Alignment – Trays Out 3/4

Preparing the Traverse unit for docking:

3. Slide the top #336 sub slide plate inside the cutout to the left or as far as it will go without force (pictured down).

4. This permits the other end of the #336 slide plate to engage gear #331.

5. Rotate the #331 gear (cw) so the plastic arm of the sub plate points past the triangle cutout, all the way left as shown. This is the elevator position.

6. The rear Traverse portion of the mech is ready for docking with the front tray assembly.

7. Optional - At the middle tray area (fig 4), you may manually rotate the stocking motor gear so the black gear hole lines up here. It will pwr to this position anyway.

8. Plug in the mech’s 3 ribbon cables and test.

rear

#331 gear

front

left Figure 3Figure 4

cutout

Slide # 19



5 Disc Mechanism Assembly Transfer Alignment – Tray In 4/4

Fig 5 – Traverse assembly elevatored up to tray level. Note position of #333 tray load lever for elevator operation.

Fig 6 – Traverse motor moves #333 lever to pull tray 1 in.

Fig 7 - #333 lever slips under tray 1.

Fig 8 - #333 lever pulls tray 1 into gear #331 on the other side (not shown).

Gear #331 grabs the tray teeth and pulls the tray into the laser assembly.

rear

Lever #333

Laser area Stock

area

III. Trays moved from the middle stock area must be transferred to the laser area.• Tray transfer is made after the traverse

assembly elevators to the desired tray level.• The traverse motor uses arms to pull the tray

into gear #331. Details in slide 4/4, above.• SW4 opens (fp 8251) to tell the micro the tray is

in.

Operational Concept Conclusion

Gear #331

Slide # 20












SA-PT660

SA-PT760

SA-PT960

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Slide # 21



Mechanism Access for Troubleshooting

Fig 9 – cover removal Fig 10 – spindle magnet plate

Access - Cover removal to view the mechanism

1. Left fig 9 - Push down on the 2 plastic catches and slide the top plastic cover ¼” rearwards to unlock.

2. Lift up the top plastic cover about ¼” for clearance and slide out toward the front to unhook the 2 tray stop arms.

3. Right fig 10 – Remove the spindle magnet plate by pulling in on the 2 plastic catches, then lift the plate up and out.

¼”

up

out

¼”

Slide # 22



Mech Troubleshooting. Is it the Mech or the Circuitry?Troubleshooting concept: The fastest way to find out if the circuitry is causing the mech problem is to check the sensors. When they turn on, they ground out the micro input lines, proving each sensor is OK.

Procedure:1a. Note the

position of the tray in the jammed mechanism (pictured left).

1b. Unplug the ribbon cable from socket CN2011.

2. Measure the voltage at each of the CN2011 socket pins. The voltages should be identical to the ones listed on the next page.

Default = Tray 1 loaded Defect - All or some trays OutDefect -Trays 2-5 loaded (shown is tray 3 loaded)

Default tray 1 position

Fig 11

Fig 12

Fig 13

rear Isolation

Slide # 23



Mech Troubleshooting. Is it the Mech or the Circuitry?

When the mechanism does not work correctly, is the problem mechanical? Is it a sensor under the mech? Is it on the main board by the microprocessor?

Isolation Procedure:1. Note which tray is in the laser assembly. Unplug the ribbon cable at CN2011.2. Compare the dc voltages at the 11 pin connector (without the cable inserted) to the

“No cable” column voltages shown below. If any are different, the main board is at fault. Check the pull up resistors and check the main board for cracks.

3. Note the position of the trays in the mechanism. Reconnect CN2011.4. Compare the dc voltages at the same CN2011 connector to the corresponding

column in the chart below (cable inserted). Pictures are on the previous page. If any of the voltages do not agree with the chart below, the corresponding sensor (Q1-5, Sw3,4) is bad. If the voltages all agree, the mechanical assembly is defective or out of alignment. Replace the assembly, or do the prev. transfer alignment.

CN2011 Connector Voltage CN2011/

pin No CN2011

cable Tray 1 in

Trays 2-5 in

All trays out

CN2011/pin corresponds to:

Changes during

1 8.2V 7.5V 7.5Vdc 7.5Vdc Motor driver Vcc 2 gnd No change 3 5Vdc 5Vdc 5Vdc 5Vdc Q4 Mode sensor Elevator dwn 4 gnd 5 5Vdc 0Vdc 5Vdc 0Vdc SW3 Top sw 6 5Vdc 0Vdc 0Vdc 0Vdc Q1 UD (lever

sensor) Trays stocked

7 0Vdc 0Vdc 0Vdc 0Vdc Motor fwd 8 0Vdc 0Vdc 0Vdc 0Vdc Motor rev 9 5Vdc 0Vdc 0Vdc 0Vdc Q2 close (gear

sens)

10 5Vdc 0Vdc 0Vdc 5Vdc Q3 home (gear sens)

Tray moves back / forth

11 5Vdc 0Vdc 0Vdc 0Vdc Q5 open (lever sens)

H at tray out

Slide # 24












SA-PT660

SA-PT760

SA-PT960

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center SW

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Slide # 25



5 Disc Mechanism Laser Replacement 1/5 – Removed from any play position

Setup –

Move Mech to PLAY position:

A. Power the unit on, select DVD and let the micro automatically move the mechanism to load tray 1, play position (the default PLAY position is shown at left for understanding only *).

B. Unplug the 3 cables and Remove the mechanism.

C. Turn the mech over.

Go to the next page.

Panasonic CR-14 Mechanism -

Default Position (no discs)

If the mechanism is replaced, The TRV / laser assembly is transplanted to the new mechanism.Mech p/n = RD-DDC026-S

Traverse/Laser p/n = RD-DDtx002-V

front

back

Fig 14

Mech p/n = RD-DDC026-S

Traverse/Laser p/n = RD-DDtx002-V

* Verification is from the front panel tray compartment. Trays 2-5 are seen below but tray 1 is recessed (loaded).

Trays 2-5

Tray 1 inside

Front view

Slide # 26



5 Disc Mechanism Laser Replacement 2/5 – Removed from play position

D. Removing the Laser assembly from the bottom in play position:

1. Locate the bottom of #335 TRV slide plate and move the catch up as shown.

2. Slide #336 sub slide plate to the right as shown until the grooves in the slot are revealed (permitting the traverse assembly to lift out).

3. Go to the next page.

back

front# 336

# 335

Fig 15

Slide # 27



Removing the Laser assembly:

3. Lift up the TRV assembly in the direction of the two arrows shown.


front

back

5 Disc Mechanism Laser Replacement 3/5 – Removed from play position

Fig 16

Slide # 28



5 Disc Mechanism Laser Replacement 4/5 – Installation

Reinstalling the Laser assembly:

4. Before dropping the laser assembly into the TRV assembly observe the two areas (A & B) outlined.

5. During the insertion, mate the pin of the laser slider (A) to the mechanism’s corresponding groove (B).


B A

Fig 17

Slide # 29



5 Disc Mechanism Laser Replacement 5/5 – Installation

Reinstalling the Laser assembly:

6. Drop the laser assembly in.

7. Slide the lever to the left as shown in arrow 2.

8. Make sure the catch is back down.

9. Finished. Turn the mechanism over and connect the mech’s 3 ribbon cables to the remainder of the unit.

4

Fig 18

Slide # 30








General Operation 15Concept & Alignment 16Failure? Mech or circuitry? Access 21Laser Replacement (removal & install) 25




SA-PT660

SA-PT760

SA-PT960

T

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center

center SW

T

R

center

SW

Slide # 31



Power Supply Block for Stby, Pwr On, Isolation.

1. Output volt @ w5713

2. FdBk volt at w5711

Defect area

30Vdc 1.5Vdc Normal Operation

Lower than 30V Higher than 1.5V Reg circuit (IC5801, Q5802)

Lower than 30V Lower than 1.5V Output Stage (IC5701, T5701, D5702)

Higher than 30V Higher than 1.5V Output Stage (IC5701, T5701, D5702)

Higher than 30V Lower than 1.5V Reg circuit (IC5801, Q5802)

Dividing a PS problem to the output or regulation stage with 2 voltages.

Plug In, Power ON Sequence1. Press Power ON2. Fan turns on - Starts Noisy3. Hello is displayed4. Last Mode used is displayed.

1

2

Measure voltages. Look up voltages on chart below for the defect area.

Slide # 32



Power Supply Circuit

Slide # 33












SA-PT660

SA-PT760

SA-PT960

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center SW

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Slide # 34



PT760 Protection Troubleshooting Concept

Slide # 35



PT760 Protection Circuit

Slide # 36



F61 / F76 error code Repair procedure (1/2)Use the protection diagrams for strategy information (p32-33) and the layout diagram (p25-26) to locate test points. The main strategy below is to first isolate the problem to one of 5 boards.

Board Isolation:

F61 Error Code

1. Even if the fan blades were spinning, replace the fan if the 3 pin CN5501 fan connector voltages are 7vdc, 0V, and 0.6Vdc (normal = 7V, 0V, 0V) at power on. See Protect diagrams.

2. Isolate the problem to the D Amp board – The problem is on the D Amp board if the unit remains powered on (no F61 error code) with CN5050 unplugged (disconnected). Go to A.

3. Isolate the problem to the SMPS board – The problem is on the SMPS board if the unit remains powered on (no F61 error code) with CN5802/pin 4 removed from the plug and the connector plugged back into the socket (with wire 4 missing). Go to B, next page.

F76 Error Code

1. On the Main board, unsolder CN2008/pin 21 OR remove jumper w2866 (layout diagram page 25).

2. Turn the unit ON. Does the Unit shut down with an F76 error code?

a) The unit remains ON (no F76 error code). The problem is on the power supply board or DVD module. Go to C, next page.

b) The unit still shuts off with an F76 error code. The problem is on the main board or power supply bd. Go to D, next page.

Slide # 37



F61 / F76 error code Repair procedure (2/2)

A) D Amp Board1. If the voltage at +

C5133 is 0.6Vdc, one of the output ICs is bad. Check the speaker terminal voltages to find out which +/- pair is more than 0.6Vdc at power on. The terminal that is 0.6V or more has a bad output IC. +C5133 = 0Vdc means the output ICs are all good.

2. If the voltage at fan CN5501/pin 3 = 0.6Vdc, replace the fan. 0V = norm.

3. If this CN5501/pin 3 fan voltage is normal at 0Vdc before shutdown, cut jumper W5002. Reconnect CN5050 & power On. Unit stops shutting down? Replace Q5640 & Q5641.

4. If cutting W5002 does not stop the shutdown F61 error code, replace SMD Q5101,Q5102.

B) SMPS Board1. Keep CN5802/pin

4 disconnected.

2. Use the layout diagram to locate and measure the +30V and -30V and fan 18V (CN5500/pin1) . Missing? Trace it to its source using the simplified PS diagrams.

3. If the voltages are all present, replace TH5860, Q5861,2 and QR5802.

C) Power Board1. Resolder

CN2008/pin 21 or reconnect jumper w2866 (removed previously).

2. Unplug 50 pin ribbon cable at main board CN2001 and power on the unit. No more F76 error code? Replace the DVD module

3. If F76 still appears, replace Q2921, Q2922 and R2913.

D) Main or Pwr Board1. Resolder CN2008/pin 21 or

reconnect jumper w2866 (removed previously).

2. Remove jumper w2753 so the unit will not shutdown.

a) If the unit still shuts down with an F76 error code, - replace the pull up resistor (R2051) at IC2001/pin 43 and then the micro IC2001.

b) If the unit stops shutting down, Check all the 11 power supply voltages listed on the layout diagram.

• If one is missing or excessive, trace it to its source.

• If the voltages are all normal, check the main bd. protection parts (D2945, Q2919, Q2909, Q2923,4 and related zeners.

F61 Error Code F76 Error Code

Use the layout diagrams (slide 25-26) to locate jumpers and key parts.

Slide # 38












SA-PT660

SA-PT760

SA-PT960

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center SW

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Slide # 39



Audio Processing Concepts

Slide # 40



Audio – Speaker Output Waveforms

No Audio @ spk term Music or Voice Audio @ spk term

Background sine wave is modulated with voice audio that averages above and

below the 0V center line (PAM).

Digital Scope snapshot at the Speaker Terminals

Spk Terminal Output = background sine wave at 1.4Vp-p @ 375kHz. Duty cycle = 50%

Average spk DC voltage = 0VdcSame output with or without speakers.

Normal “RF” waveform at the speaker terminals even when there is no sound!

Typical voice waveform at the speaker terminals

There is a constant 1.4Vp-p minimum signal with the digital (PAM) audio.

PAM = Pulse Amplitude Modulation

Units with a digital power output IC always outputs a sine wave at the speaker terminals

Output IC is ON * but may be muted or no audio is input.

* Output ICs can be turned off from the mute input. 5V = norm, 3V = mute, 0V = Off.

Slide # 41



Sample Audio Problems – Troubleshooting Methods

Audio Troubleshooting Isolation Methods1. No Audio Causes (all inputs dead)

a) Pwr Supply loss – check for + 30Vdc at pwr on. (see layout diagram)b) No Osc input – check for 4.5Vp-p (375kHz) at pin 1 of each output IC5000-5400/pin 1.c) Mute input – check for normal (unmute) 5Vdc at CN2009/pins 12, 13, 17. d) Mute input – check for broken headphone jack Sw at CN2007/pin 11 [5V = hp in, 3.5V = hp out]

2. Missing 1 or more channels (remote is needed)

a) Mute – check for normal 5Vdc at each output IC5000-5400/pin 23 (last pin).b) No Osc – check for 4.5Vp-p (375kHz) at each output IC5000-5400/pin 1.c) Use the Audio Process diagram info to select “S Music” then scope the audio at CN2003 pins.

3. Hum - Unplug CN5050 and power the unit on.a) Hum still present? – “Damp” board problem. The board’s gnd should not touch the chassis.b) Hum gone? – SMPS or Main board problem. (Main transformer T5701 if lightning damage)

4. Mute Causesa) Headphone plugged in instructs the micro to mute the spk output (ck sw at CN2007/pin 11) .b) Unplug the tuner (from the main board) to see if it is killing data communications.c) Check the mute voltages at CN2009/pins 17(all spk mute), pin 13 (frt & Sw mute), pin 12 (cent

& Surr mute). Normal voltage = 5Vdc. 0V = mute.d) DVD board no communications or its 50 pin cable is defective / damaged.

5. Low volumeNormal signal levels when the volume control is max at 50 are at the audio processing concepts diagram, lower left corner box. Vp-p Levels are with the “S Music” On and Off.

Refer to the Audio simplified diagram and layout

PT760/960 remote N2QAYB 000 214

PT660 remote N2QAYB 000 210

Slide # 42












SA-PT660

SA-PT760

SA-PT960

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center SW

T

R

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SW

Technical Guide For 2008-9 models: 6 Home Theater …diagramasde.com/diagramas/otros2/PANASONIC...

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Transcript of Technical Guide For 2008-9 models: 6 Home Theater …diagramasde.com/diagramas/otros2/PANASONIC...