Step-by-step CD32 lens replacement (with pics)

[plasmab]

Originally Posted by wmsteele

This is exactly why I suggested the rubber washers, It will move the laser assembly up slightly, preventing any case grinding / disc damage when the CD is spinning. It wont alter the distance between the CD and the laser, only the distance from the case.

Rubber washers made no difference.

[davidino78]

Hi plasmab!
Do u have solved?New laser lens can read now?
Tanks

[plasmab]

Originally Posted by davidino78

Hi plasmab!
Do u have solved?New laser lens can read now?
Tanks

No Couldnt figure it out.

[Amiga1992]

That's so weird, I wonder what happened.

[victor_cc]

Originally Posted by Akira

Now, for some people, after they did the original/CDR test above, the unit wouldn't read shit or read partially. This means that you have to do some tweaking to the potentiometers that calibrate the CD unit. There are five potentiometers in total and varied ways people swear by about how to go at them. A word of warning, these pots are VERY, VERY sensitive, so you have to do MINOR adjustments to them and remember how they were originally. For this my recommended way to do it is to measure the value they are set at with a multimeter, by putting a probe in the middle pin and another one on one of the sides (always the same side!). The pins are easily reachable on the bottom of the controller board PCB (where four pots are found) and on the back side of the lens' PCB.

I didn't have to do this tweaking but just in case I measured them all. I had to measure the controller PCB ones in the 20k Ohm range and the lens one in the 2k Ohm range.

I won't delve into this method because I didn't do it but more assistance is found at Stedy's page: http://www.ianstedman.co.uk/Amiga/Pa...dex/index.html
He doesn't go into touching the lens' potentiometer at all, though. FOL had recommended to ONLY touch the lens potentiometer and leave the controller board ones alone. If I was you and had this issue, I would start moving the lens pot before I try dealing with 4 pots at the same time. Good luck though, and although some people recommend taking a pic or marking with marker where the pots originally were, take my advice and measure it all with a multimeter and write it all done, it won't get more precise than that.

I hope this helps people revive their CD32s, if you have any further questions don't hesitate to ask in this thread! I'll respond to the best of my abilities.

Hi,

Thanks for such a great post.

In my case I don't need to replace the lens but just [hopefully] adjust the potentiometers. I hope that you can help me with questions related to your explanation:

- Where is the 5th pot? I was only able to find the 4 FEG, TEG, FEB & TEB pots.

- Could you explain further (or illustrate with a pic if possible) where exactly are the pins to use with the multimeter?


My story is the following:

After having an Amiga 500 during my youth and loving it very much, I had to give it away and move to a PC that was better suited for my university studies just when the CD32 came out at 1993. I would have given an arm to get a CD32 at that time.

Anyway, I had the chance to get a CD32 a few weeks/months ago to try to revive the good old times. I got it without power supply and I had to use a 3rd party PSU for starters (Taifu AC Adapter (5V 2A, 12V 2A) ). Then, I tried CD-R copies and nothing worked so I started to panic until I read in EAB that there were ways to tune the CD reading.

With my very limited electronics skills I tried to follow:
- http://www.ianstedman.co.uk/Amiga/Pa...32_Info/index/
- http://eab.abime.net/showthread.php?t=82828

I only managed to go from CD-Audio glitchy playback to very smooth playback moving well between tracks, etc. but playing CD32 CD-R games had exactly the same result:
- A very few games take minutes to get to the first screen and then nothing.
- 99% of games just show a black screen.
- The CDs seem to spin well (doing some noise), I see no issue there.

I burned the CD-Rs at minimum speed that my drive supports: 4X


Sorry for the long post, I considered creating a new one but I didn't know what was more appropriate.

Cheers,

Victor.

[Amiga1992]

Originally Posted by victor_cc

In my case I don't need to replace the lens but just [hopefully] adjust the potentiometers.

I have to clarify, this is the last resort, not the other way around. Changing the lens is easier and more prone to success than adjusting the potentiometers. if you read my tutorial through, you will realize I say to first change the lens THEN try that if it didn't work. So I would really suggest to you to get a new lens.

As such, I have not ever touched the pots, do not recommend doing so, and I cannot help you much, but I'll answer what I can.

- Where is the 5th pot? I was only able to find the 4 FEG, TEG, FEB & TEB pots.

Did I make a mistake? I'll correct it (and I apologize).
Oh, I remembered. There is another pot on the back of the lens assembly.
Again, I wouldn't touch any of these especially the one on the lens.

Could you explain further (or illustrate with a pic if possible) where exactly are the pins to use with the multimeter?

The pins I used are the pins of the pots, so, on the opposite side of the board where the pots are. Hope that explains it. As I said, don't want to open the CD32 to take a pic of this.
If you see Stedys 's pic, you can see where the pins for each pot are: http://www.ianstedman.co.uk/Amiga/Pa...-adjusters.jpg

Anyway, as I said, get the new lens, they are dirt cheap if you follow my instructions.

[victor_cc]

Originally Posted by Akira

I have to clarify, this is the last resort, not the other way around. Changing the lens is easier and more prone to success than adjusting the potentiometers. if you read my tutorial through, you will realize I say to first change the lens THEN try that if it didn't work. So I would really suggest to you to get a new lens.

As such, I have not ever touched the pots, do not recommend doing so, and I cannot help you much, but I'll answer what I can.


Did I make a mistake? I'll correct it (and I apologize).
Oh, I remembered. There is another pot on the back of the lens assembly.
Again, I wouldn't touch any of these especially the one on the lens.

The pins I used are the pins of the pots, so, on the opposite side of the board where the pots are. Hope that explains it. As I said, don't want to open the CD32 to take a pic of this.
If you see Stedys 's pic, you can see where the pins for each pot are: http://www.ianstedman.co.uk/Amiga/Pa...-adjusters.jpg

Anyway, as I said, get the new lens, they are dirt cheap if you follow my instructions.

Thanks for your reply and further clarification.

I see now that it would've been better to try to replace the lens. Initially I assumed that it would be easier to play with the pots and I even didn't read you post thinking that replacing the lens was the last resort.

Now, I ordered the lens following your recommendation. I'll come back with the result once (if) I manage to do the job.

Cheers

[victor_cc]

Hello again,

I got the new lens and finally found the time to do the replacement which was really easy following your post.

I tested some CDs and:
- Audio CDs played better than they did with the old lens.
- CD-R games didn't play at all

Then I got another CD32 to test (which played everything perfectly) where I could check the voltage difference between pot pins as you explain.

I adjusted the pots in my CD32 trying to get values as close as possible to the other CD32. Funny enough, in one of the pots (FEB) I can only get negative values whereas in the “good” CD32 the voltage difference is a positive one. I discovered that the best position for this pot seems to be the lowest negative value in its rightmost position.

All and all, after all the adjustment I was able to read all the CD-Rs that I tried with the odd behavior that many times the CD starts spinning backwards and I need to switch off/on the CD32 to try again until it starts spinning normally and then reading the CD perfectly.

I read on another post that this backwards spinning issue might be due to a weak laser that could be fixed by playing carefully with the lens pot, I will try that during the week.

Cheers

[FOL]

Originally Posted by victor_cc

I read on another post that this backwards spinning issue might be due to a weak laser that could be fixed by playing carefully with the lens pot, I will try that during the week.

It will not be the laser pot, if its new (and thats not the only reason for disc spinning backwards). It can be because you have messed with board pots. Every machine is different and aligned at the factory to run original games / music cd's.
People also forget spindle height, this to can cause odd behaviour. With the constant closing of lid, it can cause spindle to move lower.

[victor_cc]

Originally Posted by FOL

It will not be the laser pot, if its new (and thats not the only reason for disc spinning backwards). It can be because you have messed with board pots. Every machine is different and aligned at the factory to run original games / music cd's.
People also forget spindle height, this to can cause odd behaviour. With the constant closing of lid, it can cause spindle to move lower.

The post where I read about the laser pot solution was yours. Thanks for the explanation now.

I don’t think it is the spindle weight because the only thing that was on top of the CDs was the spindle. I was testing with the CD32 naked, before putting the CD unit, cases, etc. back in place.

After my bad experience with the board pots, I don’t want to play with them anymore unless there is a clear winner move . I guess that I would settle with having to restart the CD32 every time that a CD starts spinning backwards.

Cheers

[Amiga1992]

Was your CD32 recapped? Because there could be issues , the controller board itself has some caps that go bad.

[victor_cc]

Originally Posted by Akira

Was your CD32 recapped? Because there could be issues , the controller board itself has some caps that go bad.

I'm not sure. The person that sold me the CD32 didn't mention it.

[Amiga1992]

There's also the issue that normally people recap the main board but forget to recap the controller board. I would look into that, all these machines are due for a recapping anyway, sooner or later.

[victor_cc]

Thanks, I'll take that into account but I'm a bit afraid of the recapping process. I can use a soldering iron for very basic tasks but doing a full recap with minimum quality would be too much for me.

[Amiga1992]

I feel you, I am also not comfortable with SMD components yet. I sent my motherboards to be recapped by a skilled friend. I am sure someone in Spain is doing this job. Have you checked on Amibay?

[victor_cc]

Originally Posted by Akira

I feel you, I am also not comfortable with SMD components yet. I sent my motherboards to be recapped by a skilled friend. I am sure someone in Spain is doing this job. Have you checked on Amibay?

I haven't and it is a good idea. I'll check that option.

Cheers

[wmsteele]

This is whats hidden under the CD controller shielding...



The above is after a recap, some of the original caps were bulging but luckily hadn't started to leak.

If your doing a recap the following are needed for the controller board...

1 x 2.2uf 50v
1 x 4.7uf 35v
1 x 47uf 6.3v
2 x 33uf 6.3
4 x 100uf 16v
6 x 10uf 16v

C102 - 4.7uf 35v
C103 - 10uf 16v
C104 - 33uf 6.3
C108 - 100uf 16v
C117 - 10uf 16v
C118 - 10uf 16v
C121 - 10uf 16v
C123 - 47uf 6.3v
C128 - 10uf 16v
C129 - 10uf 16v
C130 - 100uf 16v
C201 - 100uf 16v
C202 - 100uf 16v
C203 - 2.2uf 50v
C211 - 33uf 6.3v

[victor_cc]

Originally Posted by wmsteele

This is whats hidden under the CD controller shielding...

Thanks for the information, it is very useful.

[spudje]

Once this guide will come in handy for me too. First let me grab a backup laser. Can I just buy any replacement lens (Sony KSS-210A or KSS-210B) that is sold for cheap (cheaper than on ebay) on Alilexpress? Or should I go for something that explicitly lists CD32 like this one https://www.ebay.de/itm/Origianl-CD-.../112768352552? while I guess that's just a DIY box hoping to earn more money

[Amiga1992]

Originally Posted by spudje

Can I just buy any replacement lens (Sony KSS-210A or KSS-210B) that is sold for cheap (cheaper than on ebay) on Alilexpress? Or should I go for something that explicitly lists CD32 like this one while I guess that's just a DIY box hoping to earn more money

As the guide clearly says, do NOT buy anything specifically marked CD32, it's a fucking rip-off. Read the guide thoroughly

Any laser that has the exact same model and make will be a drop-in replacement. Make sure you get one exactly like the one your CD32 already has. Mine has a 210A. But not all models do. Disassemble the thing, look at the model markings, search for that on eBay or wherever, and get the cheapest you can find.