AppleCD 300e Plus CD-R performance

[btb]

I've got an AppleCD 300e Plus, and it works pretty well. I know you aren't really supposed to expect them to read CD-Rs, but this one does, albeit not very well.
Interestingly, it often reads them only when "cold" - if I have a CD-R that won't read, I'll switch off the power to the drive, wait twenty minutes and try again, and it works. Is this a known failure mode of a specific component like a capacitor? I don't believe it's the power supply as I've run the drive outside the enclosure, using a different supply, and it behaved the same way.

Also, I've heard that older drives may be able to read CD-Rs (and CDs in general) better if you boost the laser's current slightly (possibly there's a trimmer on the head assembly) - does anyone have experience with that on this or similar drives?

 

[NJRoadfan]

These drives read CD-Rs just fine when new. It is likely capacitors if it is a temperature sensitive issue.

 

[Phipli]

They do usually read CDRs, although not all brands well. They will not read CDRWs.

Try cleaning the lens :

Cleaning the Lens in a ’90s Apple CD Drive

Cleaning the Lens in a ’90s Apple CD Drive 90s CD-ROM drives frequently struggle to read CDRs (home written discs). Sometimes this can be helped by using another brand of disc or writing the …

stuffandnonsense.elephantandchicken.co.uk

 

[Byrd]

The optical drive PCB has electrolytic caps, I'd have a look around and replace based on what you're saying. Adjusting the potentiometer on the laser lens is also a workaround, but increases the laser intensity which can lead to reducing the lifespan of the laser. I'd just clean the lens with a cotton tip dipped in IPA over adjusting the laser.

I also find "new" CD-R burnt discs work well in these older drives but the more they are used, with fine scratches as with normal use, they struggle over time.

 

[3lectr1cPPC]

I think the caps are only on the original 300 caddy load? Maybe? Go ahead and check, I’m unsure of this but google has no info on it.

 

[btb]

It definitely has a handful of electrolytics. They're all tiny (though not surface-mount) so I don't think I have replacements handy. Any reason not to use tantalums if I have them around?

I need to figure out something I can use to test caps without spending an arm and a leg...

 

[3lectr1cPPC]

If they aren't SMD caps then they probably won't be leaking (definitely not a guarantee, but more unlikely), but they're still 30 year old electrolytic caps that could need to be replaced. Tantalum caps should be fine, just make sure you use a higher voltage replacement if for example, the cap is on the 12V rail, where you'd use a 25V tantalum cap instead of a 16V original. Tantalum caps are weird.