I would like to repeat my request posted here several times: To replace an old diode with a modern one.
But I lack the knowledge to adapt the APC - circuit of an old type like the very common Sharp-LT022MC to a modern diode.
As I wrote before, the company QSI produces laser diodes that could be a good base for repair.
Original designs differed in how anode and cathode of the laser diode and monitor diode are connected together.
QSI offers all variants. Adapter PCBs have to be designed, trivial.
http://qsilaser.com/download/Infra_Red/QL78F8SX_2019.pdf
I also have a batch of Rohm diodes, I think they are RLD-2WNM2
I also have adapter rings from the 9mm housing of the "classical" diodes to the 5.6mm of modern diodes.
So if ManoloMos or ASAMS have a candidate to replace an old type with a modern type, I could donate the parts.
Datasheets of the Sharp and Rohm attached to calculate the APC.
But I lack the knowledge to adapt the APC - circuit of an old type like the very common Sharp-LT022MC to a modern diode.
As I wrote before, the company QSI produces laser diodes that could be a good base for repair.
Original designs differed in how anode and cathode of the laser diode and monitor diode are connected together.
QSI offers all variants. Adapter PCBs have to be designed, trivial.
http://qsilaser.com/download/Infra_Red/QL78F8SX_2019.pdf
I also have a batch of Rohm diodes, I think they are RLD-2WNM2
I also have adapter rings from the 9mm housing of the "classical" diodes to the 5.6mm of modern diodes.
So if ManoloMos or ASAMS have a candidate to replace an old type with a modern type, I could donate the parts.
Datasheets of the Sharp and Rohm attached to calculate the APC.
Attachments
in post #9 under
https://www.diyaudio.com/community/...laser-diode-its-the-lens.385706/#post-7374156
one will find further information
Hello! I have not tried it, but I think it should work? Most likely you will have to apply the APC circuit from a modern diode. By the way, the Chinese from Polida has taken root very well with me. Changed on two drives CDM1.
Hello, please write your phone number in private messages, I am also from Ukraine, I have a few questions regarding KSS-272A
According the attached images of NOS parts it seems to be at least two versions:
1) KSS-272A RP "8-848-244" (older version in white package)
2) KSS-272A RP "8-848-244-II" (successor version in darker package)
In the late 1990s, when the KSS-272A was still readily available (I ordered mostly from Gehado - at those days German's distributor for SONY parts) and there available for low cost (90,- DM).
I only received versions in the dark packaging (MK-II).
What could have been the differences to those in the white package (without MK-II) ?
Maybe in the used laser diodes ?
1) KSS-272A RP "8-848-244" (older version in white package)
2) KSS-272A RP "8-848-244-II" (successor version in darker package)
In the late 1990s, when the KSS-272A was still readily available (I ordered mostly from Gehado - at those days German's distributor for SONY parts) and there available for low cost (90,- DM).
I only received versions in the dark packaging (MK-II).
What could have been the differences to those in the white package (without MK-II) ?
Maybe in the used laser diodes ?
Attachments
Hello everyone,
I found some SLD104 diodes on ebay and bought 2 pieces. I have already replaced one in an optical drive. Since I don't have the necessary equipment and I don't have much experience in electronics, so I cannot adjust the laser beam, I tested the new diode as it is. Unfortunately, although the laser beam is visible, the player does not read the disc, nor does it even spin it. Do you have any idea where I could start the diagnosis? In any case, this is an experiment, because I bought a disassembled Sony 559ES, for parts, with a defective laser.
I found some SLD104 diodes on ebay and bought 2 pieces. I have already replaced one in an optical drive. Since I don't have the necessary equipment and I don't have much experience in electronics, so I cannot adjust the laser beam, I tested the new diode as it is. Unfortunately, although the laser beam is visible, the player does not read the disc, nor does it even spin it. Do you have any idea where I could start the diagnosis? In any case, this is an experiment, because I bought a disassembled Sony 559ES, for parts, with a defective laser.
Это очень сложно сделать в условиях быстрого доступа, тем более нет уверенности в том, что эти диоды оригинальны и соответствуют параметрам, как указано в таблице данных. Для начала необходимо выяснить значение рабочего тока диода, одновременно контролируя его мощность генерации уже в собранном блоке. Физический диод должен быть установлен максимально точно в посадочное место старого диода. Далее самое сложное, регулировка фотодетектора, его в любом случае нужно будет срывать с места и заново регулировать. Остальное это навыки и понимание того, что вы делаете.
Успехов!🤝
Успехов!🤝
@dimon68 thanks for reply.
How can I find out the operating current of the diode? Where should I measure? The photodetector adjustment part is difficult, I don't have the necessary equipment for adjustment. As far as I know, since the disk is not detected/rotated, the diode power cannot be measured/adjusted.
How can I find out the operating current of the diode? Where should I measure? The photodetector adjustment part is difficult, I don't have the necessary equipment for adjustment. As far as I know, since the disk is not detected/rotated, the diode power cannot be measured/adjusted.
Для измерения мощности диода нужен специальный прибор, Laser Power Meter.
Ток диода смотрите в datasheet, он должен быть в пределах 50mA. не более.
Нужно одновременно контролировать ток и мощность излучения.
Без навыков и подручных средств эту идею реализовать практически невозможно.
Но всё равно желаю вам успехов.
Ток диода смотрите в datasheet, он должен быть в пределах 50mA. не более.
Нужно одновременно контролировать ток и мощность излучения.
Без навыков и подручных средств эту идею реализовать практически невозможно.
Но всё равно желаю вам успехов.
Attachments
Заменил диод в CDM1 но это однолучевая система,
с трехлучевой будет ещё сложнее.
Ток измеряется на резисторе, обычно он 22Ω в схеме APC, по закону Ома.
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Thanks. According to schematics, there are 2 resistors, one of 2k2, and one of 10 ohms, next to the base, respectively the emitter of the transistor in the APC circuit (if the schematics presented here is correct).
I mus appologise to all of you, I'm not trying to discover the wheel, just doing some practice. 🙂🙂
Thanks in advance.
I mus appologise to all of you, I'm not trying to discover the wheel, just doing some practice. 🙂🙂
Thanks in advance.