portable dvd player audiosonic. fault . spindle motor not turning. model KM0502

hi , i have a audiosonic portable dvd player , model KM0502.

the problem with it is , is that when u insert a dvd disc ,it doesnt turn, the laser moves ok, and it says " disc not inserted " i then connected a 1.5 volt battery to the motor , and it turned ok.

so i presume the power supply section on teh pc board is damaged.

would it be possible to make up a simple reg supply just for the motor ? the thing is , i dont have a clue as to what voltage the motor is ?

anybody know ?

thanks, mark k

Reply to
mark krawczuk
Loading thread data ...

I'm afraid your diagnostic logic is way off beam here. The fact that the disc does not spin up, is not a sign that either the motor, or its drive / power supply circuitry is faulty. Most likely, the laser is not obtaining focus, so the spindle motor servo is not being turned on by the system control micro. First ensure that the sled drive is working correctly by manually moving the laser out towards the disc edge, then reclosing the door. Open it again, and ensure that the laser has 'homed' back to the disc centre. If this checks out ok, try a CD in the player, rather than a DVD. If a CD plays, but not a DVD, suspect a defective laser ( although not always ). If neither type of disc plays, then you likely have a digital processor / decoder problem. Either of these problems probably render the unit landfill, unfortunately ...

Arfa

Reply to
Arfa Daily

So the laser focuses before the disc spins up?

--
Pierre Salinger Memorial Hook, Line & Sinker, June 2004

COOSN-266-06-25794
Reply to
Meat Plow

In most cases, yes. Sometimes, if focus cannot be obtained on the first try sequence, the spindle servo will pulse the motor a little, to rotate the disc a few degrees, before trying again, in case it was trying to read through a jammy fingerprint. Some players just go ahead and spin up the disc and look for a focus lock, followed by any old data coming off the disc, that they can then get spindle and tracking servo locks on, but by and large, the sequence is :- check optical block is home, if yes, turn on laser and initiate focus search. When focus lock obtained, turn on spindle and tracking servos. Read data and use to fine tune servos. Read and display disc menu or TOC.

Arfa

Reply to
Arfa Daily

Thanks for the explanation. Way back when I was working on this kind of stuff if I recall correctly, the disc always spun up first. Since consumer CD players were in their infancy back then in the early 80's, maybe the logic control was limited in how the laser accomplished a disc check. Also this could be a way to save a bit of power on portables by not wasting it to spin an empty motor?

-- Pierre Salinger Memorial Hook, Line & Sinker, June 2004

COOSN-266-06-25794

Reply to
Meat Plow

Maybe, but I just fixed a Toshiba home player today the wouldn't spin up, and rejected the disk. If I loaded the disk and spun it manually, it would pulse a few times, the sled would track and then it would reject.

Turned out to simply be a dirty lens. Aside: Lacking alcohol, which I normally use....simply moistened a cotton swab with plain water, and it did the trick (dried it off, of course).

I remember the first time I encountered this problem...on a Technics CD changer. I farted around with the spindle motor and associated circuitry for hours before doing a simple lens cleaning. That's all it needed. That was maybe ten years ago, and the unit was used when I bought it...perhaps 1992 vintage.

Always clean the lens first! It can't hurt; and (most?) often is the entire fix.

jak

Reply to
jakdedert

ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.