Troubleshooting CD Players

Low output could be caused by shorted muting transistors.
I did some research and found out that muting transistors are used to mute the final stages of audio equipment as a safety measure during on/off operation.
So I tried to locate them on the D300 I have now open on my table. I think I saw 2 transistors but from the schematics (attached) it seems they are just the power transistors for the outputs. And it also seems Cabridge went high end and used relays instead of transistors to mute the analog outputs.
Am I correct? I've just learned this - Thank you all guys, if anything, I'm learning a lot of good stuff here...
 

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Well, thank you very much for the nice comments!

Once you get it apart and can find out if it really is a bent spindle you can also measure the disk height. Please take a few photos when you can.

If it's bad perhaps we can work something out. Either I loan you the tools or you send it to me, I don't see a problem with that. If the disk height is different than the standoff that I made I can cut another one. I have more material and access to a metal lathe at work. And I have 10 new motors here, 22mm shaft.

As far as the shaft length goes, check if the upper clamping disk has a through-hole in it. My Denon's do, so a longer shaft is actually not a problem because it passes through the hole in the upper clamping disk without any interference.

Cheers,
James
 
Well, thank you very much for the nice comments!

Once you get it apart and can find out if it really is a bent spindle you can also measure the disk height. Please take a few photos when you can.

If it's bad perhaps we can work something out. Either I loan you the tools or you send it to me, I don't see a problem with that. If the disk height is different than the standoff that I made I can cut another one. I have more material and access to a metal lathe at work. And I have 10 new motors here, 22mm shaft.

As far as the shaft length goes, check if the upper clamping disk has a through-hole in it. My Denon's do, so a longer shaft is actually not a problem because it passes through the hole in the upper clamping disk without any interference.

Cheers,
James
Very kind of you!
It would be probably easier to send the motor to you....
I'll send pictures when I'll have the time for disassembling it. First I'd like to upload a video of the motor spinning so you guys can estimate if it is really wobbling too much...
But looking at the output section I spotted another problem. A capacitor may be gone as you can see in the picture I'm attaching.
So probably dr*audio was right, this thing was not working since before it was shipped. The seller gave the money back and he also didn't care about having the CDP returned, I could scrap it myself....
 

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Yes, it has a muting relay. The first thing to try is see if the relay is on or off and whether it is shorting the output to ground.
The stuff at the base of the cap is glue.
 
Yes, it has a muting relay. The first thing to try is see if the relay is on or off and whether it is shorting the output to ground.
The stuff at the base of the cap is glue.
The D500SE has just arrived. It will take a few hours until I can get my hands on it. I think I will keep it hooked to the system by digital output for a while, before opening it and seeing what I can do.
I'm gonna need advice on how to check the relays... But possibly not until the weekend... ;-)
However, I am reading the intenal converter is practically a Dacmagic of the times. I should upgrade my Project Dacbox E by buyng a used Dacmagic and that would solve everything about the D500SE.
The D300SE is still waiting for me to do something...
 
I have an Onkyo DX-1800. CDs play, but in the background you can hear distortion, especially in quiet parts. Hard to describe, kind of a scratchiness. Some CDs are worse than others. All CDs tried are pre-recorded, no CD-Rs, etc. With the cover off it all appears ok to my untrained eye. Drawer works quickly, CDs spin up, and play. It's definitely the cd player, does it on 2 different systems. Not sure where to begin?
 
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I have an Onkyo DX-1800. CDs play, but in the background you can hear distortion, especially in quiet parts. Hard to describe, kind of a scratchiness. Some CDs are worse than others. All CDs tried are pre-recorded, no CD-Rs, etc. With the cover off it all appears ok to my untrained eye. Drawer works quickly, CDs spin up, and play. It's definitely the cd player, does it on 2 different systems. Not sure where to begin?
Low laser power. You are hearing bit errors. I haven't found a reliable source for the laser. It's a kss210A. You could search eBay and check feedback. If the seller sells mostly lasers and they have good feedback there is a chance they may be good.
 
I grabbed one off the bay, they had sold 178 of them so we'll see how it goes. Any tips for replacing or is it pretty straight forward?
 
I grabbed one off the bay, they had sold 178 of them so we'll see how it goes. Any tips for replacing or is it pretty straight forward?
1. You need an anti static work station to do this on. Get or make a grounded wrist strap.
2. Before you install the new laser there is a solder blob on the back of the little circuit board that protects the laser from ESD. Remove the shorting blob with a soldering iron and solder wick. Wear the wrist strap and ground it when you handle the laser.
3. I think you can replace the laser without removing the mechanism, but you have to remove the drawer.
4. Power up the player and push the open button so the drawer goes out.
5. turn off the power and unplug the AC cord.
6. Carefully, and SLOWLY push the drawer in all the way.. It will now be free to slide out.
7. Remove the top cover of the player and push the drawer out. I think there are 2 screws on the rear of the drawer that have to be removed in order for the drawer to come out.
8. There is a machined post on the right side of the mechanism that the laser slides on. There are plastic caps on each end of the post secured by small screws. Remove the screws, supporting the mechanism with a finger underneath as you push on the screw. Set the screws and caps aside.
9. Now you can lift up the post and carefully lift the laser out, unplugging the 2 connectors as you do it. They are color coded on the old laser. The new one may not be color coded so take note which connector goes where.
10. Carefully plug the cables into the new laser, supporting the little PCB as you do it.
11. Slide the post into the bearing on the new laser and install the new laser in the same way as the original. Apply 2 - 3 drops of light machine oil to the post on both sides of the laser. ALSO APPLY 2 -3 DROPS OF OIL TO THE TOP BEARING OF THE DISC MOTOR.
12. Push the drawer in all the way and reinstall the screws.
13 Hold the drawer in place while turning the power on. the mechanism will rise and the drawer timing will now be correctly set.
14. For best performance the adjustments in the service manual should be performed, using an oscilloscope, but it should work pretty well without doing that.
 
Well, thank you very much for the nice comments!

Once you get it apart and can find out if it really is a bent spindle you can also measure the disk height. Please take a few photos when you can.

If it's bad perhaps we can work something out. Either I loan you the tools or you send it to me, I don't see a problem with that. If the disk height is different than the standoff that I made I can cut another one. I have more material and access to a metal lathe at work. And I have 10 new motors here, 22mm shaft.

As far as the shaft length goes, check if the upper clamping disk has a through-hole in it. My Denon's do, so a longer shaft is actually not a problem because it passes through the hole in the upper clamping disk without any interference.

Cheers,
James

Before taking it apart, I'd like to show you a video of the spinning CD. Could you judge from here that it may be a bent spindle?
 
1. You need an anti static work station to do this on. Get or make a grounded wrist strap.
2. Before you install the new laser there is a solder blob on the back of the little circuit board that protects the laser from ESD. Remove the shorting blob with a soldering iron and solder wick. Wear the wrist strap and ground it when you handle the laser.
3. I think you can replace the laser without removing the mechanism, but you have to remove the drawer.
4. Power up the player and push the open button so the drawer goes out.
5. turn off the power and unplug the AC cord.
6. Carefully, and SLOWLY push the drawer in all the way.. It will now be free to slide out.
7. Remove the top cover of the player and push the drawer out. I think there are 2 screws on the rear of the drawer that have to be removed in order for the drawer to come out.
8. There is a machined post on the right side of the mechanism that the laser slides on. There are plastic caps on each end of the post secured by small screws. Remove the screws, supporting the mechanism with a finger underneath as you push on the screw. Set the screws and caps aside.
9. Now you can lift up the post and carefully lift the laser out, unplugging the 2 connectors as you do it. They are color coded on the old laser. The new one may not be color coded so take note which connector goes where.
10. Carefully plug the cables into the new laser, supporting the little PCB as you do it.
11. Slide the post into the bearing on the new laser and install the new laser in the same way as the original. Apply 2 - 3 drops of light machine oil to the post on both sides of the laser. ALSO APPLY 2 -3 DROPS OF OIL TO THE TOP BEARING OF THE DISC MOTOR.
12. Push the drawer in all the way and reinstall the screws.
13 Hold the drawer in place while turning the power on. the mechanism will rise and the drawer timing will now be correctly set.
14. For best performance the adjustments in the service manual should be performed, using an oscilloscope, but it should work pretty well without doing that.


Printed and ready to go...thanks!
 
Replacement laser coming tomorrow, so I thought I'd take out the old tonight. On step 9 I'm unable to remove the laser. Does the top white gear need to be removed? There is a black guide on the left. Underneath is a piece of plastic, so can't lift from that side and the gear is in the way on the right.

DSC_0025.JPG
 
Only way I could get it out was by removing the screw on the small PCB board, carefully pushing to one side and angling it out. All back together and the cdrom does not spin and is not recognized as being in. I can see the laser go up and down 3 times with no cdrom in. Using a camera I can see a flash of light 3 times. So either the laser is bad or I damaged something on the swap.
 
An update to my situation here and many thanks to everybody who offered help:
The D500SE works fine through the digital outputs and after all what I needed was a good and cheap transport to hook to a Dac that I will possibly upgrade in the future. The analog output is completely dead. I tried spraying some deoxit, cleaned the plugs.... now way. I can't see anything worng on the internal Dac board so I'd have to take it out and check each connections. Maybe one day...
The D300SE: I posted a video of the supposedly wobbling motor. I opened the D500SE - same Sony transport and laser - and it wobbles as well, maybe even more, but it reads the discs promptly and even if it is rather noisy, it works fine. So the D300SE has maybe a bad laser, not a bent spindle. I could probably pass it to a friend who can deal with it. Or I should by a new laser and resell it.... we'll see.
I've decided to keep the D500SE in my system because it is the superior model. I could have swapped the transports and see if the D300's outputs work, but as I said I was actually looking for a better CD transport than the Philips DVD with no display I was using since my Oppo 980 went dead. I've got the refund for the defective D300 and I bought the D500SE for 50 euros. Worth it, since the digital outputs are good.
Again, many thanks to all the contrinutors to this thread and esecially to dr*audio who started it - I learned a lot!
 
Only way I could get it out was by removing the screw on the small PCB board, carefully pushing to one side and angling it out. All back together and the cdrom does not spin and is not recognized as being in. I can see the laser go up and down 3 times with no cdrom in. Using a camera I can see a flash of light 3 times. So either the laser is bad or I damaged something on the swap.
Did you remove the solder blob?
I forgot about the gear (I was writing the instructions from memory :)) You have to remove the gear.
Put the original laser back in. If it detects the CD, send that piece of crap laser back to China and try another seller.
 
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