Its looking like a problem with or around IC503. The master clock is running (you checked with the freq meter). RFCK 1/4 is the signal divided down in frequency by four but the main RFCK is missing to begin with.
Worth checking pins 38 and 39 as its possible a problem there could inhibit something internally within the IC.
In fact its always worth going round any IC and seeing if any other voltages are amiss but its looking a bit like the IC is faulty at the moment.
Worth checking pins 38 and 39 as its possible a problem there could inhibit something internally within the IC.
In fact its always worth going round any IC and seeing if any other voltages are amiss but its looking a bit like the IC is faulty at the moment.
today I have changed complete audio amp board where the IC-503 is located from another CDP which has some different fault (do not read discs, but spindle motor is OK) and the result is OK. motor does not spinns, it is OK so the problem was on the audio amp board.
but I have anotherproblem, CDP does not read the discs as the other CDP. this one was able to read the CDs and now is not. I wonder why, I thouhgt reading (tracking,focusing and moving tray) makes on servo amp board ICs 204,304...
whoaaa it never ends
but I have anotherproblem, CDP does not read the discs as the other CDP. this one was able to read the CDs and now is not. I wonder why, I thouhgt reading (tracking,focusing and moving tray) makes on servo amp board ICs 204,304...
whoaaa it never ends
The laser pick-up connects to the audio amp board, you may have noticed. This is shown on the circuit diagram of the servo amp board as "audio amp board 1/2".
Tracking balance and offset, and focus bias, are adjusted on that section of the audio amp board. They may need re-adjustment for the different pick-up, but you don't have a 'scope.
You could swap the boards back again and swap ic503, but it might be easier to fix the other machine.
Tracking balance and offset, and focus bias, are adjusted on that section of the audio amp board. They may need re-adjustment for the different pick-up, but you don't have a 'scope.
You could swap the boards back again and swap ic503, but it might be easier to fix the other machine.
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aah, ofcourse Ive got it 
the fact ist I am not such a technician as most of you (that is the reason I am asking may be stupid questions for you) and I do not have special equipment. for this kind of IC it is for me risk to swap it.
well, I need to buy some required equipment or new CDP.
anyway, thank you very much for help
the fact ist I am not such a technician as most of you (that is the reason I am asking may be stupid questions for you) and I do not have special equipment. for this kind of IC it is for me risk to swap it.
well, I need to buy some required equipment or new CDP.
anyway, thank you very much for help
Easy... once you have a bit of experience
Use solder braid to remove most of the solder first and then jewellers screwdriver to gently lift each leg as it is heated with the iron.
Its a bit different to this but you get the idea,
http://www.diyaudio.com/forums/parts/127924-working-smd-how-do-without-specialised-tools.html
Use solder braid to remove most of the solder first and then jewellers screwdriver to gently lift each leg as it is heated with the iron.
Its a bit different to this but you get the idea,
http://www.diyaudio.com/forums/parts/127924-working-smd-how-do-without-specialised-tools.html
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