CD32 Laser

[Drake008@]

Has anyone tried to tweak the laser to recognize CDs better? Mine is at 1192 Ohm (?). I try to tweak em down to 890 and see if it works.

Audio Cds work much better now! But how deep can I go. Maybe he can read CD-RWs?

Tweaked down to around 750 ... my AmigaOS3.5 is now recognized. Time to put out my "new" Paravision SX-1.

[Rochabian]

I've tested this method too with success!!!!
It works well for me too
Before, my CD32 does have difficulty to read CD-R
Now it works great with every CD-R
I can' t remenber the value of the potentiometer that i've set but it works
I've tested too with CD-RW without success
I think it uses a different method of reading & the laser need to be set very high (too high??)
I don't want to test it to burn the laser............

[mabus]

Just burn the CDR slowly, it will work?

[musashi5150]

I've never had any trouble with CDR on my CD32 system.

[FOL]

At the end of the day, the CD32 is a standard Audio Mechanism, using a SONY KSS-210 A or B, it will never read CD-RW's as they need closing. They are priced at around £7 now and are disappearing as hardly anything uses them anymore.

Turning the laser power pot down (anti-clockwise) should'nt have the effect of making it read better, as when a laser goes low emission it normally needs turning up (clockwise).

Well thats how it is in my experience, and I have been working on mech's for the last 10 years.

Some other tips, that will help. The spindle and sled motors can go faulty, thats another common problem i come across. To help stop this happening, is to spray a little WD40 into the motors, then let it run for a few mins.

I can safely say, i have burnt disc's for my CD32 at high speeds and they all work fine. That might be cause I replaced the laser and corrected a mistake commodore made on the circuit board, where 2 capacitors are in the wrong way round (seen this on every CD32 I have opened so far), just after aquiring it.

[Chain]

Originally Posted by FOL

That might be cause I replaced the laser and corrected a mistake commodore made on the circuit board, where 2 capacitors are in the wrong way round (seen this on every CD32 I have opened so far), just after aquiring it.

Can you mark it on some photo ie. from bboah, pleease

[FOL]

Originally Posted by Chain

Can you mark it on some photo ie. from bboah, pleease

I can, but rather not mess with my last remaining CD32 as my other and sx1 blew up, .

You cant miss the 2 caps, the tops are budged. They are the 2 close to the expansion connector. If the non White strip (posative) of the caps are going to the + markings on board then they are in the wrong way round.

They are 2 caps on the 5V rail, which might explain why people have power problems when using expansions like SX1 etc etc.

If you really want a pic, ill see what i can do.

[FOL]

Sorry for double post,

Thanks to dexther for posting his pics of CD32 Board (if that is his CD32, the caps are wrong way round, ).




As you can see in the above pics, the tops are buldged on the 2 I have ringed in red.

Both need to be replaced and placed in the other way round to pic above, so left hand side cap, need the neg (white stripe) towards the top, and the right hand side 1, need to have the neg (white stripe) towards left.

As I said every CD32 I have opened has had this problem, so it must be all CD32's. Even though the CD32 functions, it can cause problems. I would love to have a circuit diagram, so i can investigate this in more detail.

Best way to confirm 100%, is to put meter probe on ground contact (screw hole) and the non white stripe leg of capacitor and you will find it reads dead short.

[demoniac]

Originally Posted by FOL

I can safely say, i have burnt disc's for my CD32 at high speeds and they all work fine.

I remember reading this article where the CD-Rs were burnt at different speeds. The result was that the max speed burn had less errors than 1x. I assume this is the fact that most drive manufacturers have 1x for legacy support only.

[alexh]

Originally Posted by FOL

I would love to have a circuit diagram, so i can investigate this in more detail.

http://www.ianstedman.co.uk/Download...schematics.zip

[FOL]

Originally Posted by alexh

http://www.ianstedman.co.uk/Download...schematics.zip

Thanks,

1 is definately on the 5V rail, on the power schematic (1000uf). Im pretty sure the other is on the Processor coupling schematic (1000uf). Ill confirm this on the weekend when I get time.

[lennonlives]

Hey, could anyone point out to me how to do the laser pot tweak, maybe with a photo? My new CD32 refuses to read Sony and Verbatim CD-Rs. Burnt them on three different burners. No go.

[Drake008@]

Originally Posted by lennonlives

Hey, could anyone point out to me how to do the laser pot tweak, maybe with a photo? My new CD32 refuses to read Sony and Verbatim CD-Rs. Burnt them on three different burners. No go.

Well you have to disassemble the Laser from the drive. on the unit is a little screw (the pot) you put a multimeter on the connectors to look where your Ohm stands and put it a bit down. Try 20 to 30 down. After that put everything together again and test. When it works it works. If it won't work disassemble again and put the pot down again a bit. Don't put it down too much or you'll blow the laser. It could be that you have to put the pot up instead of down.

[lennonlives]

Hey Drake,

it worked perfectly! I've done pot tweaks before, but not on the CD32 so far. I hope I got the right screw. At least now Sony CD-Rs are working perfectly. Verbatims are still giving problems, but I'm happy where I stand now.

Thanks!

[FOL]

Originally Posted by Drake008@

Well you have to disassemble the Laser from the drive. on the unit is a little screw (the pot) you put a multimeter on the connectors to look where your Ohm stands and put it a bit down. Try 20 to 30 down. After that put everything together again and test. When it works it works. If it won't work disassemble again and put the pot down again a bit. Don't put it down too much or you'll blow the laser. It could be that you have to put the pot up instead of down.

Or just turn it clockwise slightly. (Clockwise ups the power, Anti-clockwise lowers the power). I doubt you would burn the laser diode out if you turn it up to high. Only found DVD lasers dont like being turned up to high.

These lasers are comment, and cost around £12 to £15 pounds. The laser in question is a SONY KSS-210B.

Another thing, have you tried cleaning the lens with a cotton bud and IPA (100% Alcohol)? It might just be dirty rather than low emission.

If after all that it still plays up, let me know, Ill see if I can find you a laser in work.

[FOL]

Originally Posted by lennonlives

Hey Drake,

it worked perfectly! I've done pot tweaks before, but not on the CD32 so far. I hope I got the right screw. At least now Sony CD-Rs are working perfectly. Verbatims are still giving problems, but I'm happy where I stand now.

Thanks!

Doh, took me ages to reply, lol.

If you havent cleaned the lens, then just upping the laser power pot could kill the laser at any time.

As its normally the build up of dirt on the lens that caueses the initial problem.

[Reynolds]

@FOL #5

Dunno, but my friend who repairs a CD32 laser said this Sony head is quite common, and if I want he can choose even by price as well. Don't think it will really disappear in the near future. (Okay, when we'll have only BluRays, etc., then maybe But then the typical amiga-ish "I'll find out a workaround to solve this old laser-problem" will rises up

[FOL]

Originally Posted by Reynolds

@FOL #5

Dunno, but my friend who repairs a CD32 laser said this Sony head is quite common, and if I want he can choose even by price as well. Don't think it will really disappear in the near future. (Okay, when we'll have only BluRays, etc., then maybe But then the typical amiga-ish "I'll find out a workaround to solve this old laser-problem" will rises up

Not as common as 1 year ago, and the price is slowly climbing. KSS-213B is more common now, and even that is slowly going.

[Stedy]

Hi,

I have some notes somewhere on the resistance values of my Cd32 once I tweaked it.
My old CD32 laser tuning guide is here, http://www.ianstedman.co.uk/Amiga/Pa...dex/index.html

@FOL

All CD32s have the 1000uF power supply capacitors backward, the silkscreen is backwards so all the parts got inserted incorrectly.

Ian

[FOL]

Originally Posted by Stedy

Hi,

@FOL

All CD32s have the 1000uF power supply capacitors backward, the silkscreen is backwards so all the parts got inserted incorrectly.

Ian

Not sure what you ment by this. What do you mean silkscreen, I mean im an electronics engineer myself and have never used this term (or are you talking about the printed text on the board?). Are you confirming all CD32's have 2 caps in the wrong way round.

As for your guide, i emailed a few years ago regarding altering the laser tracking etc etc. It shouldnt be done (your just asking for trouble), as its only ever the lasers that cause problems, i.e. laser goes low emission due to dust partical formation.

At most, you should clean the lens as you describe, then if its still playing up, then boost the laser, via the laser power pot (which is mounted to the laser).

I have been repairing these mechs for over 10 years now, and only once have I ever adjusted the focus gain, tracking etc etc. Never done so again, as it caused so much problems. Cleaning and boosting the laser normally solves problem and if not, a replacement laser is needed.