A few months ago “surfing” into Marketplace looking for nothing, I saw a Cd player Pioneer PD8500 announced as “not working but well conserved. OPU must be changed. 20 bucks”. I think: high risk, low amount, ok let's go. The seller was right. The dead OPU had two defects. (1) Low power laser and (2) no movable lens. The mummy was the extinguished PWY-1011 pioneer pickup.
My first visual inspection was the laser power adjust trimmer, suspecting the easy way: full throttle for solve some past failure. And it was, minimum resistance regulation = high current = short laser life. First cause revealed.
The second seeking was for a locked lens or his armature. No news, all was ok. Then, I think, some driver burned, connector or power source out of spec. None of them. All were ok. Next step, resistance of focus and tracking lens coils. Voilá, the focus coils in open circuit, the tracking coils ok (8 ohm). Looking more deeply I found one of the copper tails from the base to the movable part broke, apparently . Second cause was revealed.
Starting with the last issue, I tried to re-weld the broken copper tail, but it was so short and in such a small space that I decided to drop off the 4 tails and replace them with longer wires. The donor was the cable of an apple earbud. After a surgery with magnifying glass, flux, tin soldering iron and patience, all the tails were left reconnected. Silicon glue was applied into welds as an effort dissipator. I had to be very very careful with the rubber suspension. In my opinion, the worst design ever made for lens stabilization (but I´m not a japanese engineer).
I follow. All reassembled, resistance checked (14 ohm focus, 8 ohm tracking), powered on and… the lens goes back to life!!, like a dog wagging its tail. But the laser intensity remained very low. I did not care.3
I put a CD, powered on again, and the focus detection shows began: the nudges for the spindle motor, the swing of lens, the seeking magic sound… but NO DISC fatal error. I did not care. News tests would begin. Laser current measure was 65mA, high, but no so much; power laser measure no possible (who have a pwr meter in this days?). Then a comparison with a healthy cd player, via cell camera, gave low power. Cleaned lens, lubed rails, re-adjusted tilt, but nothing. The fail was the same.
Then, the fact had to be faced: laser diode had to be passed to a better life, and replaced. Here, in a crossroad of change LD or try with other OPU, I took both: buy and replace the laser diode and develop an adaptation for other compatible OPU. The LDs selected were two: SLD105VL from Sony and RLD78MYR1 from Rohm. Why?, both 780nm, 5mW, AKA pinout and they were the best sellers on Aliexpress :|.
The OPU selected was the KSS313. Why?. Because this is cheap, with stock in Argentina and his dimensions appropriated to fit into the carriage, or was it what I expected.
The OPU came first, and surprise: the geometry dont fit any with the carriage… the second crossroads: sacrifice the original carriage or develop a new one, via 3D printing. The second was the election. After hours and hours of measuring, design, trial, re-adjust, the piece was builded.
Regarding the connections between the KSS313 and the board, a cross cable was necessary. The KSS´s flex connector was´nt compatible with the board. When all the parts were mounted and energized, the lens moved, and the LD goes shining. Welll done. A few tests revealed a high current in the KSS´s LD. Why??. Because the RF amplifier, a TA8137 Toshiba has different input sensitivity LD photodiode. Looking for a datasheet, they do not exist on the web (neither deep). Then I emailed Toshiba, and they responded to me (unbelievable!) that this IC wasn´t sold for a massive market and was a special development. Another Pioneer vaulted secret. Investigating other pioneer models, I could see that the issue was the VR for LD power adjustment. The KSS had a 2.2k and the required must be 4.7k. Changed and success!.
With the LD in his comfort zone, the RF signal remained absent. Aghhhh. And now what?. Looking again, I found that the KSS´s PDIC had some contact unsoldered. Surely my KSS OPU was a second hand or surplus. Once corrected this, the RF signal, or some similar, appeared at test point TP1. Yes!!. But not so good. A lot of electrical noise was present as an RF signal. New solutions were applied, shielding, cable re-routing, testing and testing, all resulted unsatisfactory, and discouraging. With a sledge hammer to destroy all in mind, the purchased LDs arrived from China, 4 months after. This is Argentina's style.
The last chance would be the change of LD. The main difference between Sony and Rohm is the focal point. An essential spec for any optical geometry. By similarities, the Sony was similar to the original (none with codes or ID). With a major surgery, the new LD was installed, and tested. It did shine!!!. But.. no focusing was possible, again. Unmounted the sony and mounted the Rohm model, conducted to the same road end: laser on, focus not. The sledgehammer came back.
But, while I saw a photo review of this story, a strange little shiny on the laser lens aroused my suspicion. Watching through a 6x zoom other defects appeared. The lens surface was damaged, with a scratch and a barely noticeable opacity.
And here, the savior ManoloMos magically appeared in this thread https://www.diyaudio.com/community/...ed-and-lost-substitution-and-repaired.390773/. The useless KSS was the lens donor that once changed, and with a new Sony LD installed, the focus signal was detected!!!!!!. Yes!!!!.
Followed by hours and hours of settings in grating, axial and radial tilt, LD current, mech adjustments, spindle balancing, the first tracking closed loop could be achieved and a decent RF eye pattern reached.
It was a lot of effort, technical discovering, schematics readings, included the Cd ISO red book studying, a dead, abandonded, misstreated CD player returned to the life.
Today not all the CDs can be readed, the CDR or CDRW usually fail. But, the commercial works in high level.
I´m apologize about my english, but you, patient reader, if reached this part, you will not give importance.
My first visual inspection was the laser power adjust trimmer, suspecting the easy way: full throttle for solve some past failure. And it was, minimum resistance regulation = high current = short laser life. First cause revealed.
The second seeking was for a locked lens or his armature. No news, all was ok. Then, I think, some driver burned, connector or power source out of spec. None of them. All were ok. Next step, resistance of focus and tracking lens coils. Voilá, the focus coils in open circuit, the tracking coils ok (8 ohm). Looking more deeply I found one of the copper tails from the base to the movable part broke, apparently . Second cause was revealed.
Starting with the last issue, I tried to re-weld the broken copper tail, but it was so short and in such a small space that I decided to drop off the 4 tails and replace them with longer wires. The donor was the cable of an apple earbud. After a surgery with magnifying glass, flux, tin soldering iron and patience, all the tails were left reconnected. Silicon glue was applied into welds as an effort dissipator. I had to be very very careful with the rubber suspension. In my opinion, the worst design ever made for lens stabilization (but I´m not a japanese engineer).
I follow. All reassembled, resistance checked (14 ohm focus, 8 ohm tracking), powered on and… the lens goes back to life!!, like a dog wagging its tail. But the laser intensity remained very low. I did not care.3
I put a CD, powered on again, and the focus detection shows began: the nudges for the spindle motor, the swing of lens, the seeking magic sound… but NO DISC fatal error. I did not care. News tests would begin. Laser current measure was 65mA, high, but no so much; power laser measure no possible (who have a pwr meter in this days?). Then a comparison with a healthy cd player, via cell camera, gave low power. Cleaned lens, lubed rails, re-adjusted tilt, but nothing. The fail was the same.
Then, the fact had to be faced: laser diode had to be passed to a better life, and replaced. Here, in a crossroad of change LD or try with other OPU, I took both: buy and replace the laser diode and develop an adaptation for other compatible OPU. The LDs selected were two: SLD105VL from Sony and RLD78MYR1 from Rohm. Why?, both 780nm, 5mW, AKA pinout and they were the best sellers on Aliexpress :|.
The OPU selected was the KSS313. Why?. Because this is cheap, with stock in Argentina and his dimensions appropriated to fit into the carriage, or was it what I expected.
The OPU came first, and surprise: the geometry dont fit any with the carriage… the second crossroads: sacrifice the original carriage or develop a new one, via 3D printing. The second was the election. After hours and hours of measuring, design, trial, re-adjust, the piece was builded.
Regarding the connections between the KSS313 and the board, a cross cable was necessary. The KSS´s flex connector was´nt compatible with the board. When all the parts were mounted and energized, the lens moved, and the LD goes shining. Welll done. A few tests revealed a high current in the KSS´s LD. Why??. Because the RF amplifier, a TA8137 Toshiba has different input sensitivity LD photodiode. Looking for a datasheet, they do not exist on the web (neither deep). Then I emailed Toshiba, and they responded to me (unbelievable!) that this IC wasn´t sold for a massive market and was a special development. Another Pioneer vaulted secret. Investigating other pioneer models, I could see that the issue was the VR for LD power adjustment. The KSS had a 2.2k and the required must be 4.7k. Changed and success!.
With the LD in his comfort zone, the RF signal remained absent. Aghhhh. And now what?. Looking again, I found that the KSS´s PDIC had some contact unsoldered. Surely my KSS OPU was a second hand or surplus. Once corrected this, the RF signal, or some similar, appeared at test point TP1. Yes!!. But not so good. A lot of electrical noise was present as an RF signal. New solutions were applied, shielding, cable re-routing, testing and testing, all resulted unsatisfactory, and discouraging. With a sledge hammer to destroy all in mind, the purchased LDs arrived from China, 4 months after. This is Argentina's style.
The last chance would be the change of LD. The main difference between Sony and Rohm is the focal point. An essential spec for any optical geometry. By similarities, the Sony was similar to the original (none with codes or ID). With a major surgery, the new LD was installed, and tested. It did shine!!!. But.. no focusing was possible, again. Unmounted the sony and mounted the Rohm model, conducted to the same road end: laser on, focus not. The sledgehammer came back.
But, while I saw a photo review of this story, a strange little shiny on the laser lens aroused my suspicion. Watching through a 6x zoom other defects appeared. The lens surface was damaged, with a scratch and a barely noticeable opacity.
And here, the savior ManoloMos magically appeared in this thread https://www.diyaudio.com/community/...ed-and-lost-substitution-and-repaired.390773/. The useless KSS was the lens donor that once changed, and with a new Sony LD installed, the focus signal was detected!!!!!!. Yes!!!!.
Followed by hours and hours of settings in grating, axial and radial tilt, LD current, mech adjustments, spindle balancing, the first tracking closed loop could be achieved and a decent RF eye pattern reached.
It was a lot of effort, technical discovering, schematics readings, included the Cd ISO red book studying, a dead, abandonded, misstreated CD player returned to the life.
Today not all the CDs can be readed, the CDR or CDRW usually fail. But, the commercial works in high level.
I´m apologize about my english, but you, patient reader, if reached this part, you will not give importance.
Attachments
Thank you, you are so kindly. But it is very interesting the adaptation, more if you adapt a laser from other trademark. There is a another handicap, and is the tiny space for to do it. I know it have suppose a lot of work, essay and error, and sometimes, lost of patiente. But, we feel a indescriptible emotion when we see that... it works!
Ciao rgigante. Thanks for you comment. I´ll be very happy if you reach the resurrection of a vitnage electronics. Then fans and the earth, grateful.
Regarding to desolderin and re-soldering, none special tips. Only those related to antistatic. Such as: connect the solder to gnd in pcd at pwy1011, use some kind of semiconductives gloves or, manipulate the new LD with recently washed hands (major humidity). I never dameged LD in the past, even in the beginings, with no idea about of static and other hiden sciences
. Regarding to desoldering process I used a copper desoldering wire as the best method. -IMPORTANT-Before to start the process, make a shorcircuit on the pad near to the current adjust on the flex. Remove it once the flex connected on the mainboard.
Your pinout is correct, is an Anode-Katodhe-Anode LD config. the SLD105VL by Sony, mathc perfectly.
Once you have replaced the LD, start the current adjust from the max resistance on the preset located in the flex. And gradually reduce to reach 25-30mA. This LD has a treshold in 30mA,
Please coment us about your progress.
Regarding to desolderin and re-soldering, none special tips. Only those related to antistatic. Such as: connect the solder to gnd in pcd at pwy1011, use some kind of semiconductives gloves or, manipulate the new LD with recently washed hands (major humidity). I never dameged LD in the past, even in the beginings, with no idea about of static and other hiden sciences
. Regarding to desoldering process I used a copper desoldering wire as the best method. -IMPORTANT-Before to start the process, make a shorcircuit on the pad near to the current adjust on the flex. Remove it once the flex connected on the mainboard.Your pinout is correct, is an Anode-Katodhe-Anode LD config. the SLD105VL by Sony, mathc perfectly.
Once you have replaced the LD, start the current adjust from the max resistance on the preset located in the flex. And gradually reduce to reach 25-30mA. This LD has a treshold in 30mA,
Please coment us about your progress.