CD 16 CD loading Problem and DAC problem

When it reads CD’s it play flawless and audio is present  on the digital output ,  Analog won’t work ;-( ,

The player has been in a repair shop for CD loading problems. then the said the is laser broken and the player could not be repaired ;-o

 

 

 

 

Lets check if the SM5803 is working

Okay what is this…?! why..?!

 

DOL Data Left channel when in stop , look okay

BCKO , the bit clock, okay

Play a CD , data on DOL & DOR

I see some strandes orange dots on safety resistors  , the are burned

 

7 in total all in the + & – 5 volt

Replaced the resisitos and now  we have a working right Channel.., left is still dead…;-( , aha Left channel TDA1547 has vREF of -0.5 instead of 4.7volt…the 560 ohm ressitor is fine ..

 

Carefully desoldered sDIL IC  , -5 volt for pin 8 & 25  is correct now

bought NOS TDA1547 ….New Old Stock 😉

Repaired DAC Board

Next CD Loading , New Belt and cleaning all pulleys .

 

 

Two things I noticed: an SM5852 for the SPDIF output, but only the mute input of the SM5852 is being used..?!
The SM5852 has Digital Dynamic Bass Boost and Digital Dynamic Compression, but it’s not connected.
Datasheet : SM5852AS
The Digital filter the SM5803 has its own CPU that probably controls some of the volume or attention ,
only ATSB is connected here as an input click-clack, possibly the CPU also sets the filter to the correct input and output mode.
Datasheet : SM5803AP