DN2500F

Still sounds like a pickup to me. If it's one of those which use the Sharp pickup, I lean even more towards that conclusion.

Mark Z.

I have replaced the pick up.

So far, it's usually the pickup. I've repaired a few, and only once it was not the pickup: the customer tried to repair a noisy tray using lip grease: now the tray did not close completely.

Clean the lens, check if there is dust anywhere inside the optical parts: sometimes the mirror under the lens gets dirty. The DJ's use these machines in very hostile environment (cigarette smoke, smoke machine liquids, drinks... anything can get into the pickup!)

And remember to unsolder the short that protects the laser diode...

Matti

Thanks for your responses. I have replaced both optical blocks,(dual cd player routine annual maintenance procedure, can't have a song skipping even once when the crowds stomping to the djs beat, very embarassing for the dj and deterimental to the future of the techie who maintains his gear) and have confirmed by swapping main pcbs (the ones under each mechanism) that the fault lies in the pcb. I cant find a datasheet for the RF amp AN8805SB IC. Symptoms:

1) If no cd is inserted, laser comes on, (weak glow) objective lense performs one jump and quits.....No Disc. 2) If a cd is inserted the cd spins at way lower rpm than normal , attempts to read 3 to 4 times over a 1 minute duration and then quits. 3 distinct supplies are available, viz +5, -5, +6.8. I guess 6.8 volts would be motor drive supply, isn't it a bit too low?. However 6.8v also appears on the side that functions fine. Other ics used are m514256b, an8389s, mn414400csj, d784021gc mn19413, mn662720rd I can't decide if its a low power supply to servo section or aomething more complicated. Either way a schematic would help plenty. :) Jango.