NAD C 541I COMPACT DISC PLAYER – CIRCUIT DIAGRAM

Nad C 541i COMPACT DISC PLAYER – Circuit Diagram

PRECAUTIONS FOR CHECKING BEAM EMISSION
The laser beam of this unit is focused on the reflecting surface of the objective lens in the optical system block.  Therefore, keep your eyes at least 12 inches (30 cm) away from the objective lens when the laser diode is ON.  (Operation Check Method for Laser Diode and Focus Search Function.)
When the POWER switch is turned ON after the chucking plate is removed, observe the objective lens and confirm that the following operations are performed properly.
(The optical system should be at the lead-in area position when it is checked at this time.)
(1) The laser should be at the innermost position after the chucking plate is removed.
(2) The diffused light of the laser beam can be seen when the POWER switch is turned ON.
(3) Vertical (up and down) movement of the objective lens (2 or 3 times) will take place.

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Main board

MCU 

Display

RF amplifier

Amplifier

Power

Wiring

Exploded view

When removing the pick-up assembly, short circuit the PCB tracks on the optical block as show in the drawing in order to protect the pick-up before removal.

NOTE: Replacement pick-up assemblies are supplied with the PCB pattern already protected.

DO NOT REMOVE THE SHORT CIRCUITS UNTIL YOU HAVE FINISHED FITTING THE PICK-UP.

Laser diodes are extremely susceptible to damage from static electricity. Even if a static discharge does not ruin the diode, it can shorten its life or cause it to work improperly. When replacing the pick-up, use a conductive mat, a grounded soldering iron, and so on, to protect the laser diode from static damage.

NAD L56 DVD-VIDEO PLAYER – CIRCUIT DIAGRAM

NAD L56 DVD-Video Player – Circuit Diagram

SMPS

U-Com expander

MPEG

DVD DSP

Drive-IF circuit

NAD C325BEE STEREO AMPLIFIER CIRCUIT DIAGRAM

NAD C325BEE Stereo Amplifier Circuit Diagram

CONTINUOUS AVERAGE POWER 50 W (17 dBW) OUTPUT INTO 8 OHMS OR 4 OHMS
(Min. power per channel, 20 Hz – 20 kHz, with no more than rated distortion)

ALIGNMENTS

INITIAL

LOWEST VOLUME ADJUSTMENT

Tune the volume pot to lowest state.

Input a high voltage signal such as 5V from CD input.

Connect a oscilloscope to L channel binding posts.

Observing the oscilloscope, adjust VR301,make the output of speakers become to the  lowest level.

Adjusting VR302,make R channel output become to the lowest level by same way.

IDLING CURRENT

Level power on for a minimum of 5 minutes.

Connect a DC voltmeter toTP1 and TP2, adjust VR22 for 4mV reading on voltmeter.

Connect a DC voltmeter toTP3 and TP4, adjust VR12 for 4mV reading on voltmeter.

ISC CIRCUIT ORIGINAL ADJUSTING

Adjust the pot VR3 to make the DC voltage of the point of TP10 to the same as TP11

ALIGNMENT POINTS

CIRCUIT DIAGRAMS

CLICK ON THE PICTURES TO MAGNIFY

YAMAHA DVD-S2700 - POWER SUPPLY SMPS _ SCHEMATIC - (CIRCUIT DIAGRAM) _ DVD AUDIO/VIDEO SA-CD PLAYER

NAD C-320 - POWER AMP SCHEMATIC (Circuit Diagram) - STEREO AMPLIFIER - [2SC5200 _ 2SA1943 – UPC1237]

POWER AMP & P/S _ SCHEMATIC

CLICK ON THE PICTURES TO ZOOM IN

ALIGNMENT PROCEDURES

INITIAL ADJUSTMENT (No load connected) {A. OUTPUT OFFSET VOLT AGE}

• Connect a DC Millivoltmeter to L Channel speaker output terminals.
• Turn unit ON and adjust VR21 (100 ohms) to get the reading of 0V+/-30mV.
• Connect the DC Millivoltmeter to R Channel speaker output terminals and adjust VR11 (100ohms) to get a reading of 0V+/-30mV.

IDLING CURRENT

• Connect a DC Millivoltmeter to TP1 and TP2 and adjust VR22 (300 ohms) for 3-5mV reading on meter.
• Connect the DC Millivoltmeter to TP3 and TP4 and adjust VR12 (300 ohms) for 3-5mV reading on meter.
• Leave power on for a minimum of 5 minutes.

Repeat procedure A and B for offset voltage and idling current alignment respectively.

NAD C-320BEE - STEREO AMP - SCHEMATIC - [CIRCUIT DIAGRAM]

NAD C-320BEE - STEREO AMP - SCHEMATIC - [Circuit Diagram]

INPUT SELECT

CLICK ON THE SCHEMATICS TO ZOOM IN

KEYBOARD

POWER & AMP

ALIGNMENT PROCEDURES

I. INITIAL ADJUSTMENT (No load connected)

A. OUTPUT OFFSET VOLT AGE

1.Connect a DC Millivoltmeter to L Channel speaker output terminals.

2.Turn unit ON and adjust VR21 (100 ohms) to get the reading of 0V+/-30mV.

3.Connect the DC Millivoltmeter to R Channel speaker output terminals and adjust VR11 (100ohms) to get a reading of 0V+/-30mV.

B. IDLING CURRENT

1.Connect a DC Millivoltmeter to TP1 and TP2 and adjust VR22 (300 ohms) for 3-5mV reading on meter.

2.Connect the DC Millivoltmeter to TP3 and TP4 and adjust VR12 (300 ohms) for

3-5mV reading on meter.

3.Leave power on for a minimum of 5 minutes.

II. FINAL ADJUSTMENT

Repeat procedure A and B for offset voltage and idling current alignment respectively.

NAD DVD video player – T531B – T531C – T531AH – SMPS circuit diagrams

NAD T531B – T531C – T531AH – T512C – T512AH – DVD Video Player Power Supply Schematics

Click on the Schematics to Zoom in

NAD C521 compact disc player – schematic – mechanism exploded view

Used ICs: PCM1710U – LC78621ED – LC587206A - LA9240 – LA6541D – LB1641 – 5532

CHECKING THE BEAM EMISSION

  The laser beam of this unit is focused on the reflecting surface of the objective lens in the optical system block. Therefore, keep your eyes at least 12 inches (30 cm) away from the objective lens when the laser diode is ON. (Operation Check Method for Laser Diode and Focus Search Function.)

When the POWER switch is turned ON after the chucking plate is removed, observe the objective lens and confirm that the following operations are performed properly. (The optical system should be at the lead-in area position when it is checked at this time.)

(1) The laser should be at the innermost position after the chucking plate is removed.

(2) The diffused light of the laser beam can be seen when the POWER switch is turned ON.

(3) Vertical (up and down) movement of the objective lens (2 or 3 times) will take place.

  Laser diodes are extremely susceptible to damage from static electricity. Even if a static discharge does not ruin the diode, it can shorten its life or cause it to work improperly. When replacing the pick-up, use a conductive mat, a grounded soldering iron, and so on, to protect the laser diode from static damage.

Schematic diagram & PWB

CD11CA- Mechanism - exploded view

NAD DVD video player – T531B – T531C – T531AH – SMPS circuit diagrams:

NAD T531B – T531C – T531AH – T512C – T512AH – DVD Video Player Power Supply Schematics

Click on the Schematics to Zoom in

NAD C320BEE – Schematic – Current adjustments - Stereo amplifier

Circuit diagram - current adjustments - NAD C320BEE – Stereo amplifier - NAD C320BEE : Used semiconductors and ICs - 2SD669 – 2SC5200 – TL082D – Upc1237HA – Z86C0812PSC – 24C01 – 4094

CONTINUOUS AVERAGE POWER 50 W (17 dBW)
OUTPUT INTO 8 OHMS OR 4 OHMS IHF dynamic power (maximum short term power per channel) 8 ohms: 110 W (20.4 dBW) 4 ohms: 160 W (22.0 dBW) 2 ohms: 210 W (23.2 dBW

Schematic [Click on the pictures to magnify]

ALIGNMENT PROCEDURES.  INITIAL ADJUSTMENT (No load connected)

A. OUTPUT OFFSET VOLTAGE
1. Connect a DC Millivoltmeter to L Channel speaker output terminals.
2. Turn unit ON and adjust VR21 (100 ohms) to get the reading of 0V+/-30mV.
3. Connect the DC Millivoltmeter to R Channel speaker output terminals and adjust VR11 (100ohms) to get a reading of 0V+/-30mV.
B. IDLING CURRENT
1. Connect a DC Millivoltmeter to TP1 and TP2 and adjust VR12 (300 ohms) for 3-5mV reading on meter.
2. Connect the DC Millivoltmeter to TP3 and TP4 and adjust VR22 (300 ohms) for 3-5mV reading on meter.
3. Leave power on for a minimum of 5 minutes.
FINAL ADJUSTMENT
Repeat procedure A and B for offset voltage and idling current alignment respectively