Something you could try... and it does work but it sort of needs experience and feel for how it all works 😀 it to keep opening and closing the drawer and during brief few seconds the lens bobs up and down is to hold something reflective very close to the lens surface. Close as in a couple of mm. A shiny screwdriver, one with a bit of tinfoil taped to it... the idea is to make the lens think a disc is present and if it detects the reflected laser light it will kick the disc motor briefly (before realising its been had). Done correctly and it can tell you if the laser is at least working at a basic level. But if you can't get it to do that then it doesn't mean its faulty if you see what I mean. It comes down to luck and experience.
Do you mean the four neoprene supports ? As long as the disc can spin without fouling anything then there shouldn't be a problem. The disc clamp literally drops on to the magnetic platter so there should be no issues there.
If you set the sled away from the disc centre by turning the worm gear then it should instantly return to the correct start point the moment you open and close the tray.
Do you mean the four neoprene supports ? As long as the disc can spin without fouling anything then there shouldn't be a problem. The disc clamp literally drops on to the magnetic platter so there should be no issues there.
If you set the sled away from the disc centre by turning the worm gear then it should instantly return to the correct start point the moment you open and close the tray.
Yes. I have considered the tin foil approach. Seems like it may be akin to a western quick draw.
I didn't mean the neoprene disc in the tray but the sled suspension, but this will be taken apart when full dismantle takes place. I have set the sled at the far end and returns fine to m. switch end. Disc also spins freely if gently pushed.
I didn't mean the neoprene disc in the tray but the sled suspension, but this will be taken apart when full dismantle takes place. I have set the sled at the far end and returns fine to m. switch end. Disc also spins freely if gently pushed.
Everything you describe sounds OK.
You mean those four whitish supports, one on each corner of the mech to support it. Shouldn't be an issue there. Important thing for now is just that the disc is free to spin. This could well just be a case of a faulty laser. There's not much else left really.
You mean those four whitish supports, one on each corner of the mech to support it. Shouldn't be an issue there. Important thing for now is just that the disc is free to spin. This could well just be a case of a faulty laser. There's not much else left really.
Stripped and cleaned the whole mech throughout and now seems a lot smoother but still not spinning the disc. I turned up the laser power a tad, not full though, certainly the laser is brighter but still no spinning disc. Is it possible to adjust the position of the micro switch position i.e. to alter the laser end stop?At a loss now and I am thinking must be laser electronics? Or maybe the disc motor, although it is spinning, is it worth swapping motor and micro switch just to satisfy investigation?
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Mrbluesurf, I think you have done too few electric tests before breaking the unit apart.
Disassembly and cleaning of the optics is one of operations which can kill the transport in quite a high number of cases, despite the instructables on the internet. Another way to kill the laser is to increase the laser power arbitrarily, without proper measurement.
Since you checked both motors OK, I would also check the tracks on flat cable for possible crack or bad termination with continuity tester and magnifying glass. In addition, measuring RF signals upon CD insert/readout with an oscilloscope would greatly help you in establishing where the fault may lie.
Disassembly and cleaning of the optics is one of operations which can kill the transport in quite a high number of cases, despite the instructables on the internet. Another way to kill the laser is to increase the laser power arbitrarily, without proper measurement.
Since you checked both motors OK, I would also check the tracks on flat cable for possible crack or bad termination with continuity tester and magnifying glass. In addition, measuring RF signals upon CD insert/readout with an oscilloscope would greatly help you in establishing where the fault may lie.
I suspect you have probably gone as far as you can with this. The micro switch isn't adjustable beyond bending the contacts, which should be straight and parallel to the small plastic mounting of the switch.
One other thing to check. The platter is a push fit on the motor shaft. I've seen an odd one where its been pushed to far down altering the disc height but if that has happened then the blob of epoxy in the centre of the platter would be missing or obviously displaced.
This sounds like a (rare) case of a failed pickup at this point.
One other thing to check. The platter is a push fit on the motor shaft. I've seen an odd one where its been pushed to far down altering the disc height but if that has happened then the blob of epoxy in the centre of the platter would be missing or obviously displaced.
This sounds like a (rare) case of a failed pickup at this point.
Willi, thanks for your reply. I had checked all the tracks and ribbon etc beforehand and all are ok. The Stage works perfectly with another laser mech so it is not the main board. Disassembly and cleaning seems to be par for the course on cdm12 because of the grease hardening and I know adjusting the laser output is not good but this was a last resort, I will put the adjustment back again to where it was. Unfortunately I do not have an oscilloscope and I am not a technician.
Just to clarify, I meant the ribbon cables on the transport, not those on electronics boards.
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