My CD player was skipping tracks so I cleaned the lens and wiped and lubricated the rails.
It read the index and while playing track one it skipped ahead by a minute. I was able to skip to each track and it seemed to work fine. When I returned to track one the disc just spins and won’t play.
I’ve confirmed the laser moves up and down centers itself as it should after closing the tray. The STA341M does get very hot.
Any ideas?
It read the index and while playing track one it skipped ahead by a minute. I was able to skip to each track and it seemed to work fine. When I returned to track one the disc just spins and won’t play.
I’ve confirmed the laser moves up and down centers itself as it should after closing the tray. The STA341M does get very hot.
Any ideas?
After sitting off for about 30min it worked, but experienced the same issues.
There are times when the disc is inserted it won’t spin. Other times it spins for a couple of revolutions and then stops very quickly.
There are times when the disc is inserted it won’t spin. Other times it spins for a couple of revolutions and then stops very quickly.
@Boydk you were correct it’s the worm gear. When you hit stop the motor return the laser back to the start position and it does it rapidly. This binds the worm gear and the gear it’s meshed with. If I use my finger, as you suggested, it frees the gear and plays normally.
I’m not sure what the fix is. I tend to think the spring in the arm to the left is meant to prevent the binding. Maybe it’s a weak spring.
I’m not sure what the fix is. I tend to think the spring in the arm to the left is meant to prevent the binding. Maybe it’s a weak spring.
Attachments
Well @Boydk I got it working. In order to prevent the gears from binding after hitting stop I used some thicker doubled sided tape between the CD motor and the laser. This provides some cushioning so the gears can’t jam when the laser returns home.
Any idea what the black micro switch is for behind the laser sled motor? It’s at the end of the long white plastic piece that meshes with the larger gear.
Any idea what the black micro switch is for behind the laser sled motor? It’s at the end of the long white plastic piece that meshes with the larger gear.
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It's looks to be a usual fault in this Luxman CD series. This thread is a little similar.
https://www.diyaudio.com/community/...ing-discs-trimpots-or-component-issue.405366/
About the problem, I think it's the KSS-152A laser that works bad, a adjust needed, or both causes. Ok, let's go to try adjust. VCO adjust, Focus bias, Tracking error balance are adjustments that you can perform witha n oscilloscope.
D/A converter is not a necesary adjust for this issue, but you can perform it with CD 1khz tone and an Audio Analyzer.
Well, the problem is tracking gain and focus gain, becuse we don't have any information about the "jig". What is the "jig"? I don't know, but if you look some CDs adjustments procedures like a Pioneer PD-S504 or a JVC XL-V231bk, the "jig" should be only a resistor with a capacitor for to do a low pass filter, and another resistance in other place.
I think that if you tries to perform the adjustment in these Luxman like the cited Pioneer or JVC, the adjust should be perfect.
Maybe, if nobody do it, and one day I'm boring, I try it.
This is applicable to some Sony cd players, becasuse focus gain and tracking gain is not clear too.
About the semiconductors geting hot, I think it is because focus gain is too high, so, focus gain is misaligned.
https://www.diyaudio.com/community/...ing-discs-trimpots-or-component-issue.405366/
About the problem, I think it's the KSS-152A laser that works bad, a adjust needed, or both causes. Ok, let's go to try adjust. VCO adjust, Focus bias, Tracking error balance are adjustments that you can perform witha n oscilloscope.
D/A converter is not a necesary adjust for this issue, but you can perform it with CD 1khz tone and an Audio Analyzer.
Well, the problem is tracking gain and focus gain, becuse we don't have any information about the "jig". What is the "jig"? I don't know, but if you look some CDs adjustments procedures like a Pioneer PD-S504 or a JVC XL-V231bk, the "jig" should be only a resistor with a capacitor for to do a low pass filter, and another resistance in other place.
I think that if you tries to perform the adjustment in these Luxman like the cited Pioneer or JVC, the adjust should be perfect.
Maybe, if nobody do it, and one day I'm boring, I try it.
This is applicable to some Sony cd players, becasuse focus gain and tracking gain is not clear too.
About the semiconductors geting hot, I think it is because focus gain is too high, so, focus gain is misaligned.
Could be the motor is worn out. These are simple DC motors with brushes and a commutator. As they wear, the resistance between these gets higher, so the winding current drops resulting in lower torque, eventually to the point where they won't start without a push.
It looks like a Mabuchi motor so might be easy to find a replacement.
It looks like a Mabuchi motor so might be easy to find a replacement.
If you want to test Sled motor, apply a few volts in it, 2 or 3 volts, and change polarity. If you want to test it with the IC204, apply a tiny voltage in pin2 IC 204, positive and negative voltage for to test forward and reverse movement.
The spring you cites is for join the tooths of the sled to the wheel, for avoid any movement.
Sled motor is for to move the laser pickup horizontaly, but this is a coarse movement, the mechanism who makes horizontal tracking is tracking servo. The sled motor moves with littles steps when the cd is playing, This motor does not should be the cause for the high temperature of the IC204.
The spring you cites is for join the tooths of the sled to the wheel, for avoid any movement.
Sled motor is for to move the laser pickup horizontaly, but this is a coarse movement, the mechanism who makes horizontal tracking is tracking servo. The sled motor moves with littles steps when the cd is playing, This motor does not should be the cause for the high temperature of the IC204.
Superb...... Pictures might reveal better, what you´ve actually done.
That switch is actually the stop-switch to tell the sled motor, that it has reached it´s end point. Problem is the reaction time allows the gear
to lock.
I can´t´obviously point this out excact enough, without all kinds og new suggestions coming to life.
There´s one reason.... and one reason only, that this error occurs.
The worm is worn out. The glassy surface is gone and the worms surface is not smooth anymore, which allows it to lock.
Unfortunately this wormgear, specs/measures of the worm is not found in any other product (that I know of).
No reason to try to mingle with the switch position (tried that too).
The way it works is: When you load a CD, the motor runs just enough to release the switch. (but can´t since it has locked itself)That´s where the TOC index on the CD is located. Altering switch posisition just messes TOC-read up too.
I´m sure that with the proper time and tools, the whole system could be altered with an alternative "tooth"-piece on the laser and a
different way of driving the laser sled. If one finds it worthwhile. I didn´t and tossed my 2 units.
But IT IS........ Because the gear has locked itself. The current IC 204 is capable of is not enough to get the motor lose from it´s locked position.
That´s the reason it gets hot, When the motor is not moving, the voltage keeps increasing, until it does. Problem is..... It does NOT 😉
All great suggestions, but I tend to agree with @Boydk because all it took was a bit of a nudge of the worm gear with my finger to get it working every time. Sometimes it would run 2 or three times without any issues, but eventually would lock after hitting stop.
After putting 3 layers of double sided foam tape, it’s about 2mm thick, in this area the cd player works fine. I think it prevents the worm gear from jamming when the laser travels to the home position.
This is the area I put the tape in. I didn’t take a photo as I wasn’t sure it would work.
After putting 3 layers of double sided foam tape, it’s about 2mm thick, in this area the cd player works fine. I think it prevents the worm gear from jamming when the laser travels to the home position.
This is the area I put the tape in. I didn’t take a photo as I wasn’t sure it would work.
