Marantz MAR770, DR-6000, MAR775 service manual CD Main Board, Troubleshooting P816

Models: MAR770 MAR775 DR-6000

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8.2.2Troubleshooting P816

Check fuse F820 and replace if necessary

OK

 

Check DC voltages

OK

+5V, +12V, -8V, VFTD (-35V),VDC1-VDC2 (3V8)

NOK

Disconnect power supply unit from CDR main board

Connect dummy load resistors 10W, 15 ohm at +5V, +12V and ground

 

Check DC voltages

 

OK

+5V, +12V, -8V, VFTD, VDC1-VDC2

 

 

 

These voltages might be somewhat higher than specified

 

 

 

 

 

 

 

 

 

 

 

OK

 

 

 

 

 

 

 

Check the +5V and +12V

 

 

 

 

 

 

 

 

 

 

 

 

 

 

NOK

 

 

 

 

 

 

 

 

 

 

 

 

 

OK

Connect the mains inlet to a mains

isolated variac

Power supply unit OK

Power supply is OK

Check : - CDR main board

-Display assy

-CD main board for DR6050

Check the path of the other faulty voltage(s)

+5V : check D856, C857, L856, C859

+12V : check D866, C867, L867, R866, D868, C869

Turn input voltage up and check voltage across C821, this voltage should be ±1.41 x Vin AC

OK

Is power supply ticking?

NO

NOK

YES

Check the functionality of the following components :

F820, R819, C820, L820, D802, C821

Check :

Load on secondary output

Overvoltage protection : L832, D814, C814, R814, R815, R816 Oscillator voltage on pin 10 of Q810 :

check C802, R810 replace Q810

Drive circuit : gate voltage of MOSFET Q825 components R812, R813, C813, R825 Regulation circuit

- Measure voltage on pin 6 of Q810 with oscilloscope

-If > 2.5V check the regulation circuit : Q810, D881

R881- R885, C881, C882, R804 - R806, R809, C804, C809

Check Vcc on pin 1 Q810 Vcc = 12V...... 16V

OK

Power supply OK

NOK

Check start circuit and Vcc supply:

 

 

R823, R834, C829, D829, R829, R811, C811

 

 

Replace Q810

 

 

 

 

 

 

 

CL 96532076_037.eps

 

 

290799

Figure 8-18

8.3CD Main Board

The CD main board is built around the compact disc mechanism VAM1250 and a loader 1250. The CDM delivers diode signals and an unequalised high frequency signal. These signals are necessary inputs for the decoder CD10. Based on these signals the decoder will control the disc. The decoder is able to control the sledge, focus motor, radial motor and turn table. When everything is "locked", the decoder delivers a digital output according to IEC958 standard, subcode to the microprocessor and I2S for reproducing analog audio signals by means of a D/A converter.

The microprocessor controls the CD10 and is slave of the master processor on the CDR main board in the DR6050. Both processors communicate via a DSA connection (data, strobe and acknowledge).

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Marantz MAR770, DR-6000, MAR775 service manual CD Main Board, Troubleshooting P816

MAR770, MAR775, DR-6000 specifications

The Marantz DR-6050 and DR-6000 are revered components in the world of high-fidelity audio systems, reflecting the brand's long-standing commitment to quality and performance. These models have gained popularity among audiophiles for their comprehensive features and advanced technologies, which cater to both casual listeners and serious music enthusiasts.

The Marantz DR-6050 is a CD recorder and player that stands out with its dual functionality. It allows users to enjoy CDs while also having the capability to record directly from various sources, including analog inputs and digital connections. This functionality is essential for those who wish to preserve their vinyl records, cassettes, or other audio formats onto CD. The machine supports CD-R and CD-RW media, providing flexibility for repeated use and recording.

One of the standout technologies in the DR-6050 is its high-quality Digital-to-Analog Converter (DAC), which significantly enhances sound performance by converting digital signals to analog with incredible accuracy. This contributes to the unit's ability to reproduce audio with rich detail and clarity. Additionally, the recorder is equipped with a Microprocessor that ensures precise recording levels and optimizes the quality of the output.

On the other hand, the Marantz DR-6000 offers similar capabilities but with an emphasis on simplicity and ease of use. Designed for users who appreciate an intuitive interface, it features straightforward controls and an ergonomic design. The DR-6000 supports multiple recording formats, including standard audio CDs, making it versatile for various playback systems.

Both models are built with high-grade components that promise longevity and reliability. They feature robust construction, ensuring minimal vibration and interference to enhance playback quality. Integrated analog and digital inputs allow for diverse connectivity options, which is crucial for users with elaborate audio setups.

In terms of audio performance, both the DR-6050 and DR-6000 exhibit impressive frequency response and low distortion levels, characteristics that are vital for a satisfying listening experience. The devices also include features like playback speed control and disc finalization options, providing the user with complete control over their audio sessions.

The Marantz DR-6050 and DR-6000 are ultimate companions for those who appreciate high-quality sound and need versatile recording solutions. With their blend of advanced technologies, clear audio output, and user-friendly designs, they remain solid choices for anyone looking to enhance their audio collection and experience.