Marantz MAR775, MAR770, DR-6000 service manual Transfer Characteristics, Hfdet Setting

Models: MAR770 MAR775 DR-6000

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Transfer Characteristics

Set the power and reset connections as described above in "1.1.1. Supply Voltages". Connect a function generator via a serial resistor of 1k5 to pin 4 of connector 1000. Use the

function generator as a sine wave generator with output level of 1Vtt. Check this AC value with an AC mV-meter connected to the input (pin 2) of the CD10 (7000) :

Frequencies

S1 and S2 “low”

S1 and S2 “high”

300Hz

10kHz

100kHz

300kHz

800kHz

1.5MHz

3MHz

Input VAC

200mV

200mV

200mV

200mV

200mV

200mV

200mV

Pin 2 at 7000

<100mV ± 20% 295mV ± 20%

310 mV ± 20%

385 mV ± 20%

655 mV ± 20%

1.1V ± 20%

1.1V ± 20%

Input VAC

200mV

200mV

200mV

200mV

200mV

200mV

200mV

Pin 2 at 7000

<100mV ± 20% 330mV ± 20%

330 mV ± 20%

335 mV ± 20%

485 mV ± 20%

760 mV ± 20%

1.1V ± 20%

CL96532086_059.eps 080999

Figure 8-30

HFDET Setting

Set the power and reset connections as described above in "1.1.1. Supply Voltages". Connect a function generator via a serial resistor of 1k5 to pin 4 of connector 1000. Use the

function generator as a sine wave generator with output level of 500 kHz, 1Vtt. Check this AC value with an AC mV-meter :

Location

F190

F192

F206

 

Voltage DC

No HF

 

HF

4.8V± 20%

 

4.8V± 20%

< 100mV

 

1.1V± 20%

4.9V± 20%

 

150mV± 20%

Voltage AC

175mV± 20%

-

-

CL96532086_060.eps 080999

Figure 8-31

8.3.8Audio Part - DAC

Description

The DAC used, is the UDA1320 bit stream, continuous calibration. I2S signals from various formats can be entered at pins 1,2 and 3. If these signals are in phase with the delivered system clock at pin 6, the DAC will reproduce analog output signals at pins 14 and 16. 0dB level is 0.85Vrms. These analog signals are at 1.65Vdc level.

The DAC has features which can be checked on the input pins. Mute will switch off the analog signals. De-emphasis is not used, since this is done in the decoder. Attenuation of -12dB is not used because this is also done in the decoder.

signal is in phase with the WS-signal. Transition of the WS always happens on a falling edge of the CLK.

DATA

DATA contains all data-bits. Data bits are set by the transmitting device, and read by the receiving device. The position of the DATA-bits within the WS-signal is very important. There are several formats for this. In our case we always use Philips I2S format, no Japanese or Sony format. The number of data-bits per channel depends on the used devices.

Timing of the I2S-bus, in case of Philips I2S is shown in the next figure :

I2S

I2S is a kind of digital audio format, consisting out of 3 lines : CLOCK, WORDSELECT and DATA.

WORD-SELECT

Word select (WS) indicates whether the data-sample is from the left or the right audio-channel. It has the same frequency as the sample rate of the digital audio signal. This can be 32, 44.1 or 48kHz. Normal polarity is low for a left sample and high for a right sample. So within the low state of the WS-line the data bits for the left channel are transferred, and within the high state the data bits of the right channel are transferred.

CLOCK

The CLOCK signal (CLK) indicates when DataTips must be set, and when DataTips must be read. The frequency depends on the speed of the I2S-bus, but is always a factor of the frequency of the WS-signal. It can be 48x, 64x, 96, 128x... .In our case it is 48x the sample rate frequency = 2.1168MHz. The

WS

LEFT SAMPLE

RIGHT SAMPLE

 

 

CLK

 

 

DATA

MSB

MSB

 

Figure 8-32

CL96532086_061.eps 080999

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Marantz MAR775, MAR770, DR-6000 service manual Transfer Characteristics, Hfdet Setting