Troubleshooting CD Players

[dr*audio]

Awesome thread. I found this thread and began reading through pages.

Based on 1st page guide, I checked the mechanism with and without cd loaded and found that drawer open/close properly but the mechanism does not rise up to the play position. It comes up half way up so does not fully touch the CD.

Is it rubber belt worn out or can it be something else? Any guide would be hugely appreciated. Thank you.

If it's a single disc player the loading belt is bad. If it's a Sony 5 disc changer the pin on the mechanism is in the wrong groove on the cam gear. This happens when someone moves the player without the locking key installed.

 

[decomo]

If it's a single disc player the loading belt is bad. If it's a Sony 5 disc changer the pin on the mechanism is in the wrong groove on the cam gear. This happens when someone moves the player without the locking key installed.

Thank you so much. I removed the belt and it looks still very good condition without any tear or wear. I will order another one just in case and see if it helps.

 

[dr*audio]

Thank you so much. I removed the belt and it looks still very good condition without any tear or wear. I will order another one just in case and see if it helps.

It is also possible the drawer timing is messed up.
To set the drawer timing:
1. Push the Open button to open the drawer.
2. Unplug the power cord.
3.. Gently push the drawer in. At some point you should feel the resistance stop as the drawer reaches the gap where there are no gear teeth.
4. Hold the drawer all the way in and power up the unit.
5. The mechanism will rise and the drawer timing will now be correctly set.

 

[decomo]

It is also possible the drawer timing is messed up.
To set the drawer timing:
1. Push the Open button to open the drawer.
2. Unplug the power cord.
3.. Gently push the drawer in. At some point you should feel the resistance stop as the drawer reaches the gap where there are no gear teeth.
4. Hold the drawer all the way in and power up the unit.
5. The mechanism will rise and the drawer timing will now be correctly set.

Thank you very much. I just tried and somehow still the same. I placed an order for replacement belt and should receive them in a couple of weeks. Once receive it, will replace old one with new and hope it solves the issue.

I manually pull the mechanism up with finger and once it is up then it reads CD okay so definitely loading mechanism issue.

 

[Nautiker]

I have a 'new' (supposedly) Pioneer PD M730 (6 disc) - it accepts discs, the disc spins but never gets past the TOC check - the disc never plays, and then the unit moves to the next disc, repeat. So, it's obviously not reading. Is there anything I can do with this or is a technician required (assuming I can find one)...?

 

[dr*audio]

I have a 'new' (supposedly) Pioneer PD M730 (6 disc) - it accepts discs, the disc spins but never gets past the TOC check - the disc never plays, and then the unit moves to the next disc, repeat. So, it's obviously not reading. Is there anything I can do with this or is a technician required (assuming I can find one)...?

Does it read the TOC? If so, the laser is bad. If not, the laser could be bad or the flat flexible ribbon to the laser could be broken. Both common problems on Pioneer players. Also could be the lens fell out.

 

[Nautiker]

Does it read the TOC? If so, the laser is bad. If not, the laser could be bad or the flat flexible ribbon to the laser could be broken. Both common problems on Pioneer players. Also could be the lens fell out.

No, it doesn't read the TOC. It doesn't appear to read anything - but I thought that the disc spinning would indicate that the laser is working...

 

[redk9258]

I have a 'new' (supposedly) Pioneer PD M730 (6 disc) - it accepts discs, the disc spins but never gets past the TOC check - the disc never plays, and then the unit moves to the next disc, repeat. So, it's obviously not reading. Is there anything I can do with this or is a technician required (assuming I can find one)...?

Is this one of those Pioneers that you load the disc upside down?

 

[Nautiker]

Is this one of those Pioneers that you load the disc upside down?

It is - to my knowledge, all Pioneer & Denon magazine CD changers load the discs label-side down...

 

[dogwan]

Is this one of those Pioneers that you load the disc upside down?

Looking at pics of that model I can tell right away it is.

@Nautiker try putting the discs in the magazine shiny side up. The laser is above the disc cartridge and the laser reads the discs upside down.

Many an old Pio cartridge player have migrated from the thrift store shelves to the dustbin because people think they don't work after loading the discs right side up.

 

[dr*audio]

No, it doesn't read the TOC. It doesn't appear to read anything - but I thought that the disc spinning would indicate that the laser is working...

It could mean that it achieved focus lock but doesn't have enough power to read data.

 

[Nautiker]

Looking at pics of that model I can tell right away it is.

@Nautiker try putting the discs in the magazine shiny side up. The laser is above the disc cartridge and the laser reads the discs upside down.

Many an old Pio cartridge player have migrated from the thrift store shelves to the dustbin because people think they don't work after loading the discs right side up.

I've owned Pioneer magazine changers for many years, I'm aware of how the discs are to be loaded... Thanks!

 

[dr*audio]

I've owned Pioneer magazine changers for many years, I'm aware of how the discs are to be loaded... Thanks!

If this was on my bench i would use an oscilloscope and look at the FOK signal and the RF signal to determine the fault. The problem with Pioneer CD players is no replacement lasers are available.

 

[Nautiker]

If this was on my bench i would use an oscilloscope and look at the FOK signal and the RF signal to determine the fault. The problem with Pioneer CD players is no replacement lasers are available.

Yeah, I know replacement Pioneer lasers are extraordinarily rare... :-( This unit is supposedly 'new/unused' (and it looks new), so I hope the laser is not dead - not sure why it would be, but if it is, the unit is pretty much ready to be recycled...

Looks like it uses either a PWY 1009/PWY1010 laser....

 

[valentair]

Hi folks, I've read the first 10-ish pages of this interesting thread, but did not find an answer to a problem that has inflicted my Technics SL-PS70 (circa 1991). The player has no problem playing original disks from start to finish, regardless of their length (it handles well even 75min+ long albums). The problem occurs when I try to play user-selected tracks - say, from listening track #3, I select track #14 to be played next --> the player's laser assembly moves to the desired track, but the laser never achieves lock on its beginning (track #14 in our example) and keeps hunting indefinitely, while the disc keeps spinning. No track is played. This usually happens with tracks that are down the playlist and close to the end of the disk. Skipping from track #3 to track #5 will not be a problem. I've cleaned the laser, but this changed nothing. What might be the reason for this deficiency and what would be a possible solution? Thank you in advice for sharing your experience with me.

 

[dr*audio]

Hi folks, I've read the first 10-ish pages of this interesting thread, but did not find an answer to a problem that has inflicted my Technics SL-PS70 (circa 1991). The player has no problem playing original disks from start to finish, regardless of their length (it handles well even 75min+ long albums). The problem occurs when I try to play user-selected tracks - say, from listening track #3, I select track #14 to be played next --> the player's laser assembly moves to the desired track, but the laser never achieves lock on its beginning (track #14 in our example) and keeps hunting indefinitely, while the disc keeps spinning. No track is played. This usually happens with tracks that are down the playlist and close to the end of the disk. Skipping from track #3 to track #5 will not be a problem. I've cleaned the laser, but this changed nothing. What might be the reason for this deficiency and what would be a possible solution? Thank you in advice for sharing your experience with me.

Some Technics players use a linear motor to move the sled, and the machined posts that the laser slides on get gummed up, causing problems like this. Clean the posts with Q tips and alcohol, moving the laser back and forth to get the laser bearings cleaned also.
Allow to dry and then put 2 or 3 drops of light machine oil on the posts on either side of the laser, then move the laser back and forth to distribute the oil.
Dupont Silicone Oil with Teflon is good.

 

[valentair]

Thank you Dr. Audio! Yes, you are correct - the laser slide is moved by a linear motor. I am attaching a picture of the assembly. Did I understood you correctly that I need to clean and then oil the metal rail (pointed with a red arrow) from the attached image?

 

[dr*audio]

Thank you Dr. Audio! Yes, you are correct - the laser slide is moved by a linear motor. I am attaching a picture of the assembly. Did I understood you correctly that I need to clean and then oil the metal rail (pointed with a red arrow) from the attached image?

No, that is just the motor pole piece. Don't lube that. The posts you need to clean and lube are underneath.

 

[valentair]

No, that is just the motor pole piece. Don't lube that. The posts you need to clean and lube are underneath.

Understood. I guess I'll need to take further apart the laser assembly to reach these machined posts. Do you happen to have a picture of similar posts? I suspect they look similar across laser assemblies that are powered by linear motors, like mine. The pic will help me identify these posts easier and lube the correct part

 

[dr*audio]

Understood. I guess I'll need to take further apart the laser assembly to reach these machined posts. Do you happen to have a picture of similar posts? I suspect they look similar across laser assemblies that are powered by linear motors, like mine. The pic will help me identify these posts easier and lube the correct part

Just move the laser back and forth, the posts are what it slides on. Captain Obvious says you're welcome.