Sega Saturn mod quit on me

[Kewpie]

Something is wrong with my modded Sega Saturn. I had it since it's release in 1995. and modded it somewhere around 2004- it wasn't until last month it stopped playing my back-up games (burned titles) its not the copies, the regions are correct.

it seems, the lens keeps reading over the back-up until it goes to the message 'no disk in drive'. After a few times, it would load one back-up but 3 minutes later, freeze and return to the main Sega screen.

It successfully plays original NTSC-region games though. anyone had this problem? can it be the mod is loose? 

[Elite Evil]

Possibly, could also be that the laser is weaker and the original pressings are easier to read than your copies?

[scorp111]

Yup that's what it is. There is a way to adjust the power calibration of the laser there is a screw on the bottom of the laser lens unit. You must be very careful while doing this this is called adjusting the POT. BIAS and GAIN. BIAS, This control sets the default DC voltage flowing through the servo coils in the laser that move the laser lens up and down. GAIN, This control sets the voltage that is added or subtracted from the bias voltage by the servo circuits for a given fluctuation.  With a disk in the Saturn unmodded should read the voltage at 2.53 V. Without a disk it should be  2.51 V. Move the POT about 5 degrees clockwise then test your backup. If the backup works then all is well after this is all said and done the Saturn with out a disk should read 2.52 V.   Good luck. This does get easier with practice.