'samsung Dvd-rom Sd-616q'

[Grzyb]

Just received this from a mate.....Can NE1 confim whether this is possible or pure bulls**t

Quote:

Just been visiting a friend of mine and his PC's DVD-Rom
drive has developed a fault. This drive is a 'SAMSUNG DVD-ROM SD-616Q' drive and is about
12-15 months old.

When trying to use it, Windows XP (Home Edition) cannot
detect a disc inside the DVD drive unit. This applies to all CD's, DVD-Roms, DVD Video discs.

The DVD ROM 'D' drive icon in "My Computer" remains unchanged/unaffected and nothing
happens

If you click the drive's icon in 'My Computer', a message appears saying:
"Please insert a disc into drive D:."  even though the disc is already inside the
drive and waiting to be read.

It has been claimed by an unhelpful person that the laser lamp can be re-aligned inside the unit
and that this will fix the fault.
I have since been re-informed by the same person (perhaps to decoy me away from the truth) that this
is NOT the case and it may be something to do with the internal power supply?

He seems to claim it can be done with just a screwdriver!

This agency claims that this is a "trade secret" yet I believe he is less experienced and less qualified than
you are to carry-out such a repair.

If you know how this can be done can you please tell me in case one of my own CD or DVD writer
drives should ever fail in the future.

Thanks....

[DoG]

In theory it can be done, just like the PSX series of consoles can have the lens realigned and have the power output increased. In practice i'm not sure how you would do it on a dvd , try places like firmwareforum.fr and look in the section for that specific manufacturer.

I have a pioneer dvd rom here, let me strip it and have a look. About the only thing that changes between drives are the cosmetics and firmware ayway so it may be a generic design.

[Grzyb]

Nice One...This has intriged my curiosity

[DoG]

Ok, here's what i found.

The laser is fixed at a right-angle to the lens, it would appear that the laser emmiter itself can't be adjusted. The lens is mounted on a "sled" in "cradle" using springs, the springs are soft and allow the sled to move around freely- i'm guessing you could check for freedom of movement in all directions. There is a PCB attatched to the side of the laser assembly (This is the same on every CD\DVD player i have messed with). On the PCB there a 2 little pot's, one of these will allow for power calibration (This is where it differs from PSX laser assembly's, i can only remember them having 1 calibration pot). IF you carefully mark each pot so you know where you started from it should be possible to recalibrate the laser, only adjust one pot at a time though, untill the drive functions again.

Of course, it's possible that the 2 pots adjust the X and Y axis of the sled movement but i couldnt see any motorised controll for adjusting the angle of the laser or lens. It could be that the "seld" is mounted inside a small electromagnetic array, this would give rise to the need for 2 pots instead of 1. I think it's just going to be a case of trial and error in adjusting the 2 pots and seeing which works best.

[Grzyb]

Thanks For The Reply...I'll pass on the Info