Pioneer cd player pots

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Hi PIY,
The only thing you can do is send it in for service. The tech should be really good at alignment and Pioneer products. Tell them the pots have been played with.

Sorry, it's not the answer you wanted.

To get it closer right now, mark the current positions. If you gently turn the control, there should be a slight indent that you can feel at the factory position. This may or may not work.

Guess what I'm recommending. I can only hope your local service choices are good.

-Chris
 
Get the service manual if avaliable. Then you would know what the adjustments do and how to make them.

Usually I mark the trimpots with a sharp marker pen their orginal positions before playing with them so I can return them to their orginal positions after mucking around witgh them. Pick a point where you can draw a line across the moving part to a stationary part.
 
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Hi PIY,
Fair enough. A 'scope with a time base of 0.5uS / div is recommended. The manual of course. I was hoping you'd have a friendly tech by your side to help.

Do not touch the diffraction grating adjustment in the head. It is very touchy. Read the instruction through twice at least. Mark the pot positions.

Good luck.

-Chris
 
the digital and servo schematic are the same for pd 8700 und 9700.

the pots are:

-focus offset: trim "fcs err" so that TP1 PIN6 gets -150 mV
-tracking error balance
(tracking server open, pickup in the middle of a disc TRK BAL on TP1 Pin 2 -> 0 V DC)
-rf level: trim laser power to get rf signal @ TP1 PIN1 1.2 Vpp
-focus gain
(you need an af generator (1.2Khz 1Vpp), 2ch-scope, 100k resistor..)

i can mailing you photos from the instructions..
 
Hi Everyone, Good evening!

I just had a PD-8700, all functions are working but the CD is not spinning.
First thing I did was checked all switches (open and clamp, Inside switch in the lens assy)and all are functional.
I checked the Spindle motor, supplied external supply (5V) and it's working fine.
Checked the Lens assembly and found the laser diode is working perfectly.
I also replaced the Spindle driver IC LA6520 thinking it might be the cause but still no joy.

Someone please help me on where to look next, I'm suspecting the system control IC but that Part is discontinued, I think. and if that's the case this CD player will be put back on the shelve. Thanking you all in advance.
 

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As a generalisation, if the lens performs the focus search routine (bobs up and down 3 times) when the tray is closed and the laser is lit during that time, then you should try and see if there are any logic transitions visible on the Fok (focus OK) data line. That looks to be pin 39 of IC151.

As with any fault finding, always check all the rails are correct and clean. The SYSCON chip (unless there is a known failure mode with them) would be way down the list of suspects.
 
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