Technics SL-PG590 repair
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- čas přidán 8. 05. 2023
- This is a very complicate failure on this machine. But what I found out is only to watch if you see the complete Video. There are Multiple failures at the same time. Also a change from a IC will not fix this issue. But have fun to watch and Please subscribe Thank you for watching weakbit
In the service manual there is a fault finding tree. I ended up down to the IC702 leg 30 where I read 2.5V, tree says this is an optical pickup failure. Then I realized that the ppl who said that the laser diode deteriorate over time and the variable resistor in the optical pickup needs to be turned to a lower ohm value were right. The CD player is unable to detect the CD as the laser diode is not as good as it was when new so it would not spin up the spindle motor. My value was 1.22 kOhm and I had to turn down to 600 Ohm to get it started again. Now the optical pickup can detect the CD, I might still need to go even lower as the first CD plays, but sometimes in a funny way. First I try another CD because this CD is as old as the player. :)
It's amazing to see people can fix issues like this.
Yes some times I've luck to fix a CD-Player! haha
I have some updates on my work. Finally i removed the mechanism from the SL-PS77D and i put it into the SL-PG590
Then the PG590 started working however it did not like to play the beginning of many discs. I removed the board on the mechanism and i turned the potentiometer very slightly clockwise. This seemed to help with playing tracks at the beginning.
However then i wanted to know if the board from the PG590 was bad so i swapped them and it also worked however the problem with playing the beginning of discs returned. I did not want to make more adjustments so i replaced the original board from the PS77D. I also suspected after reading here that the tracks and rail the laser tracks on might need lubrication. I noticed that at the end of the tracks the white grease was a little old and thick. This might have had something to do with the bad reading of the discs but i didn't experiment enough to say weather it was the adjustment of the potentiometer or the lube. I only had 3 in one oil or thick silicone grease. Usually i would use the silicone but i decided to add just a few small drops of 3 in 1 this time. I put the original board back in and everything is fine.
Conclusion is that either the laser is tired or as suggested here the mirror that reflects the laser up to the lens probably needs cleaning, i'm not sure if i can get to it.
The thing is the PS77D had some rust on the casing so i couldn't really sell it. There is very little difference except for a separated transformer and different features on the front panel, also the 77D is taller but the mechanism is the same. If swapping Mash mechanism you might need to change the front panel on the drawer to fit your main front faceplate. to do this eject the drawer and carefully with a blade or tiny flat screwdriver you can release two small plastic catches, it then slides up and off.
It's possible the potentiometer needs to be calibrated to the new driver board under the mech if you do need to change, i can not confirm this but it is what i observed.
Check the motor that positions the laser head to ensure it moves freely. If it's seized it cannot put the laser head unit in first position so the drive motor won't turn on and spin. Usually you'd need to remove the laser head position motor (long silver one on the head gear) apply a few drops of oil and provide it some power for several minutes to free it and see that it moves freely over time.
Fantastic video
Cool!
How to repair spinning direction.. my cec to 5100 spin anticlockwise..
Hi I have the same problem as you have got on this cd player same make and model also but have can't find the ic AN8389S, found them in the USA but shipping is like 50dollars which is expensive. Do you know anywhere I could get one from I live in the UK. Any help would be appreciated thanks.
Hello Ian, I'm visiting London ago 3weeks and have a look here at Aliexpress and this will be found on one of the first places: de.aliexpress.com/store/3878092/search?SearchText=AN8389S Good Luck! weakbit
I have one here. In the older Technics CD players the repair was simply to change the blue Phillips caps. I changed some caps just in case but it was still spinning slow and reporting no disc. Then i warmed the larger circuit that also contains the power supply in case any of these caps were failing and voltage might be low. I was getting around steady 4.85V on the regulator i think. However after some gentle warming it now refuses to spin so i tried putting it in the cold and still no spin, then i adjusted the small vr under the laser assembly i tried slightly both directions from original position but still no spin. I am not sure why it has stopped spinning at all. I tried to clean the lens gently with just toilet paper on tweezers but that changed nothing.
I did not have a 1uf caps so i put a 2.2uf in. I think the 1uf was ok but i have no idea why they used a 50V cap!
I will put the 1uf back and see if there is any change. The ic you changed does not use many of it's pins only a few which seem to be soldered fine. I'm putting the 1uf back in now on the board under the cd mech.
Well i've tried everything very carefully and put the 1uf back in. But it now does not try at all to spin up and comes up with no disc very quickly.
Sorry i don't see exactly what your solution was. It's very rare for ic's to go bad without another reason.
I have a similar Technics "Mash" player which works but i still prefer the older Technics CD player i have. I changed the blue caps and it works very well. It plays discs that the"Mash" player can not read or skips on.
I've tried now also more extreme turns on the tiny pot. I cleaned the 2 switches on the mech and the pot but nothing.
Not worth spending any more time on. It's even a waste of space in spare parts. lol
Hello - first I'll tell you how the init process is working. The tray will close and then the laser switch on and the feedback receiver diodes (4pieces + 2pieces track) are looking for a reflection - first the lens go up to the CD and make the focus better or/and go down and focus to the track of the CD. If this reflection is coming then the µController will turn on the PWM and spin up the spin motor clockwise fast. The EFM signal will receive over the lens and the 4pieces receiver diodes will receive this signal and bring it to the RF-Amplifier to amplify this small signal that is coming from the CD. If this will work the TOC (Table of Content) will read and then the µController know where are the tracks (on which seconds the track begin). If this is running normal the CD-Player is working.
Congratulations sir what ic sir.? For spindle?
This is a IC Technics AN8389S.
@@weakbit633 maybe same problem of CD player pioneer pd 106 won’t spin spindle motor sir where to check sir the ic? Or?
@@weakbit633 the pioneer using la6520 ic
@@cortessarge5399 Hello 1st please check if the laserpickup have a red laserlight (don't stare into the beam) if not change the laser-pickup. Then search the service-manual for this CD-Player in the internet. Search the spindle motor and the sled motor on the plan this is the same IC where it is connected to. Check it with a Oscilloscope what came out? if it is a low level signal you know you can not drive the motor with this low current. Maybe the IC is defect?
@@weakbit633 ok sir thank you very much for helping me what i have here only digital multimeter I don’t have oscilloscope sir but I will try thank you sir and more power to your vlog im always watching your vlog
Warum nicht in Deutsch?
Хлам ещё тот!!! 😂
Looks like toy from market (mainboard)..... Total waste of money