I have been given a Technics SL-P1 which does not work properly.
What happens is that as soon as I turn the power on, the laser is activated but the lens is moved all toward the disc spindle. The disc motor keeps wobbling back and forth and when I press the open/close button, the disc motor starts rotating at full speed. The display always shows 0000. I get the same behaviour with and without a disc.
If I manually open the disc tray, it detects it is open and close it correctly.
If I manually move the pick-up, it detects it is not in the centre and move it back to the inner position.
Any idea what could be wrong ? Anyone familiar with this old player ?
thanks
What happens is that as soon as I turn the power on, the laser is activated but the lens is moved all toward the disc spindle. The disc motor keeps wobbling back and forth and when I press the open/close button, the disc motor starts rotating at full speed. The display always shows 0000. I get the same behaviour with and without a disc.
If I manually open the disc tray, it detects it is open and close it correctly.
If I manually move the pick-up, it detects it is not in the centre and move it back to the inner position.
Any idea what could be wrong ? Anyone familiar with this old player ?
thanks
You can download a service manual for it from a number of places, for example: https://www.vintageshifi.com/repertoire-pdf/pdf/telecharge.php?pdf=Technics-SLP-1-Service-Manual.pdf
Maybe that will have some info on the problem.
Maybe that will have some info on the problem.
Hi, I got an interesting suggestion on another thread and what is actually happening is that the CPU is receiving a wrong signal from the RF amplifier: the servo board is notifying that RF is detected even if there is no disc or even optical pickup connected and that causes a loop in the initialisation sequence. Now I have to understand why the RF amplifier is detecting RF, maybe caps to be replaced or a faulty IC.
I surely miss a scope, I do not have it. I will try a recap of the servo board, i have pulled out some caps in the power supply section (this board has its own voltage regulators) and they are "tired". I do not have some of the bipolar caps needed (and they are hard to find also on Farnell) so i will go with the electrolytic polarised caps first. But i suspect a faulty IC because it detects RF even with the pick-up disconnected.
Indeed the servo caps were the fault. Replaced all electrolytic and it now reads CD's.
IC's and pickup are fine, it was the RF ampli with maybe a wrong signal on one of the pin.
IC's and pickup are fine, it was the RF ampli with maybe a wrong signal on one of the pin.