Sega Saturn, Model 2, NTSC-US: Disc drive intermittant

Hi all,

Have searched around but haven't found a consensus so wanted to chime in here hoping y'all could help.

I've got a Model 2, NTSC-U Saturn - chipped, originally ordered from SegaStyle. And lately I'm having weird problems with it - the disc drive sometimes (let's say 75% of the time) refuses to spin the disk. It seems to not even recognize there's disc inserted, judging by the boot screen. Doesn't matter if burned CD-R game or commercial music album on CD-ROM, just... nothing.

The confusing part is that the other 25% of the time, the machine reads it fine. Boot it up, it'll run the game no problem and play fine for as long as I've tested it (30+ minutes).

Some of the literature I've read suggests these are the symptoms of a dying laser, but were that the case I'm confused why it occasionally works flawlessly. I'm wondering if a CD door switch is not being tripped appropriately, or something.

At any rate, have any of you heard of anything like this? Do you have any ideas to pop it open and repair? (And on a sidenote, is anyone still repairing Saturns for-hire anymore? Would probably be willing to pay for a repair as I'm really tight on time these days.)

Looking forward to hearing your insights. Thanks!

Edit: Oh and it's a 32 pin.

 

It could be that the rails need greasing and perhaps there's a tooth missing in one of the gear pickups, would need close and quality photo's. Theres a video of a guy repairing a PC Engine CD-Rom console in which he was having a very similar problem here if I get the link

 

Thanks for the vid, will take a look.

The plot thickens slightly, let's see if this jogs anyone's memory: After doing some stress testing it seems that the pattern is: the console is happy for 30-45 mins after a cold boot, then craps out and refuses to read anything. However if left alone for another 2-3 hours, it's happy again for a short window after a cold boot.

 

x

 

I have a Duo-R that would work in one room (workbench) and not in another (TV room). It was easily reproducible and quite laughable as I would move back and forth. Sometimes it wouldn't work on the workbench. With a heavy FMV-intro disc, it would only work if I had an oscilloscope probe hooked up to it. I ended up just ordering a new laser, and from then on it was rock solid. I suppose I should also mention that it was also recapped, however it was the laser swap that solved the intermittent issue.

 

That's classic bad laser diode behavior. What happens is that as the diode warms up, it needs more current to maintain the same output power level, but since the diode is weak, it was running near maximum drive current anyway, and doesn't have enough headroom to increase the drive further. The reason it takes a while is that the diode mounting has quite a large thermal inertia.