OK, so adjusting didn't help. Put the pot back to where it was.
Have you access to a 'scope?
P.
Have you been through the Alignments as per the Manual?
Pin6 of TP1 to -150mV with VR103.
I am guessing you have and it still doesn't achieve Focus Lock when Program is pressed.
So, with a Disc loaded and the unit in Test Mode, when you press Program and you move the disc with your finger can you hear a 'shushing' noise? This should be the Focus Servo working but this will only happen once the Player gets Focus Lock. When Program is pressed the Laser Lights, then the Focus Coils are driven up and down (the 'S' Curve some Manufacturers refer to) usually three times. If the Laser is working correctly, the reflected Light back from the disc will at one point be at its largest. This the Player detects and remembers as the correct Focus point and the Lens will be held at this point.
At this point if the disc is moved (by your finger) you should hear the 'shushing' noise which is the Focus Servo working to keep the Lens at the correct point.
So, when Play is pressed and the Spindle Motor Servo kicks in the disc should spin. The RF waveform can be observed at this point but as the Tracking Servo isn't working at this point it will appear a little 'blurred'.
So, with your Player, you say you do see the Laser Light and the Lens driven up and down. If you move the disc at this point can you hear the 'shushing' sound.
As you say it doesn't spin when Play is pressed I am going to guess that you don't hear the shushing sound.
So, what do you see at the RF Test Point (Pin1 of TP1) when you do press Program? It will be small (If you have no Eye Pattern we are talking a fault mode of some description so it will be tiny) so adjust your 'scope accordingly. As the Lens is going up and down we are looking for a flicker of signal as the reflected light from the disc produces a signal from the Laser's receiving Diode which is amplified by the RF Amp IC (IC101) and we should see at the RF Test Point.
I am going to guess you won't see anything here and to me it is going to point towards the Laser being at fault.
Of course it could be the RF Amp IC (IC101) but I can't ever remember having to change one of these. Of course just because I can't remember changing one doesn't mean they don't fail. It could easily be this. I have changed many RF Amps in Philips machines.
However, I do remember changing hundreds of PEA1030's !!! These were not Pioneer's most reliable Laser. They had a bad habit of the Lens falling off !! (Yours doesn't look like it has ever been glued back on does it?!?!?!)
Let me know how you get on.
P.
Pin6 of TP1 to -150mV with VR103.
I am guessing you have and it still doesn't achieve Focus Lock when Program is pressed.
So, with a Disc loaded and the unit in Test Mode, when you press Program and you move the disc with your finger can you hear a 'shushing' noise? This should be the Focus Servo working but this will only happen once the Player gets Focus Lock. When Program is pressed the Laser Lights, then the Focus Coils are driven up and down (the 'S' Curve some Manufacturers refer to) usually three times. If the Laser is working correctly, the reflected Light back from the disc will at one point be at its largest. This the Player detects and remembers as the correct Focus point and the Lens will be held at this point.
At this point if the disc is moved (by your finger) you should hear the 'shushing' noise which is the Focus Servo working to keep the Lens at the correct point.
So, when Play is pressed and the Spindle Motor Servo kicks in the disc should spin. The RF waveform can be observed at this point but as the Tracking Servo isn't working at this point it will appear a little 'blurred'.
So, with your Player, you say you do see the Laser Light and the Lens driven up and down. If you move the disc at this point can you hear the 'shushing' sound.
As you say it doesn't spin when Play is pressed I am going to guess that you don't hear the shushing sound.
So, what do you see at the RF Test Point (Pin1 of TP1) when you do press Program? It will be small (If you have no Eye Pattern we are talking a fault mode of some description so it will be tiny) so adjust your 'scope accordingly. As the Lens is going up and down we are looking for a flicker of signal as the reflected light from the disc produces a signal from the Laser's receiving Diode which is amplified by the RF Amp IC (IC101) and we should see at the RF Test Point.
I am going to guess you won't see anything here and to me it is going to point towards the Laser being at fault.
Of course it could be the RF Amp IC (IC101) but I can't ever remember having to change one of these. Of course just because I can't remember changing one doesn't mean they don't fail. It could easily be this. I have changed many RF Amps in Philips machines.
However, I do remember changing hundreds of PEA1030's !!! These were not Pioneer's most reliable Laser. They had a bad habit of the Lens falling off !! (Yours doesn't look like it has ever been glued back on does it?!?!?!)
Let me know how you get on.
P.
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Hi Percy,
I did adjust the Focus Offset to 150mv.
I can also see a small flickering on my scope whenever I press PLAY that's in reference to pin 1 TP1 but I cannot hear any focus adjust from the LENS if I rotate the DISC Manually.
I might change the LENS but the part is 6X expensive than what I paid for this CD player
Do you have a spare LENS/Optical pickup?
Regards,
Junie
Do take note, it is -150mV. That's Negative 150mV. On these Players with the 'Stable Platter Mechanisms' where you put the disc in Label side down and the Laser is 'upside down' you have to adjust the Focus Offset to a Negative value.
Sorry, no.
My player doesn't use this Laser so I never 'stocked up' on the PEA1030 like I did for mine !
P.
Well,
I would say it's either the RF Amp IC or the Laser. And on a player this age I would say the Laser.
As you say the PEA1030's are not cheap.
A quick search on ebay reveals this.........
PIONEER PEA1030 LASER PICKUP (PNP-1138-B) - NEW in Factory Sealed box | eBay
and this but this is not new..............
http://www.ebay.co.uk/itm/Pioneer-P...438350?hash=item3d346b164e:g:rIQAAOSwZQRYbogV
I am disappointed that the Chinese have not made any 'fake' Pioneer Lasers. One or two of their Sony and Philips ones aren't too bad. I would think the demand is there for Pioneer Lasers. Ah well.
P.
I would say it's either the RF Amp IC or the Laser. And on a player this age I would say the Laser.
As you say the PEA1030's are not cheap.
A quick search on ebay reveals this.........
PIONEER PEA1030 LASER PICKUP (PNP-1138-B) - NEW in Factory Sealed box | eBay
and this but this is not new..............
http://www.ebay.co.uk/itm/Pioneer-P...438350?hash=item3d346b164e:g:rIQAAOSwZQRYbogV
I am disappointed that the Chinese have not made any 'fake' Pioneer Lasers. One or two of their Sony and Philips ones aren't too bad. I would think the demand is there for Pioneer Lasers. Ah well.
P.
Hi percival007, Junie,
I agree with you. However, you can check the Fok pin to see if the CD player was able to find the disc. If it does and it spins up too quickly, the E-F balance might be out, or the diffraction grating adjustment might be off. E-F balance is a very touchy adjustment and critical for the player to work. So is the diffraction grating. In service test mode, this adjustment can be safely carried out. So it may not be the head, check these things before messing with the laser power adjustment.
-Chris
Edit: I forgot to ask you to make certain the lens is securely glued down before doing anything else.
I agree with you. However, you can check the Fok pin to see if the CD player was able to find the disc. If it does and it spins up too quickly, the E-F balance might be out, or the diffraction grating adjustment might be off. E-F balance is a very touchy adjustment and critical for the player to work. So is the diffraction grating. In service test mode, this adjustment can be safely carried out. So it may not be the head, check these things before messing with the laser power adjustment.
-Chris
Edit: I forgot to ask you to make certain the lens is securely glued down before doing anything else.
Never try and check a LD with a DVM on ohms. It takes only pico second current spikes to impair or even destroy the facets within a semiconductor laser. The only meaningful tests are checking the current consumption of the LD, usually by calculation using the voltage dropped across a low value resistor already present in the LD drive circuit and secondly by using a laser power meter to measure the optical output.
The diode MD is on the same die as the laser and is used for optical power control by means of a feedback arrangement.
The diode MD is on the same die as the laser and is used for optical power control by means of a feedback arrangement.
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