Does a laser pick up have a home position?

[Dwizzle]

Hi Everyone,

 

I have recently been getting some cracking noises through my CD player like the signal was breaking down or something??

 

I tried cleaning the laser and runners and now it won't open or read the TOC/play.  It is a TASCAM player/recorder and has a CD ROM inside which has the button like on a computer, this is how I can open it to see that it will not play (the buttom in the CD player interface in what is not working). 

 

I didn't think I did anything that would have cause a problem however I must have, i did move the laser on the slider a lot by hand.

 

My question is do some CD ROMS have a home position that they use as a start point?  This is the only other potential issue I can think of unless the noise was being cause another component failing.

 

Any sensible recommendation will be appreciated and other comments will be marked out of 10

 

Thanks

Dan

 

 

 

[Equaliser]

TOC Errors usually boil down to burnt or weak lasers. There are trimpots on the pcb near the laser or on the servo board that can be adjusted for laser tracking and power of the beam. Too strong and it won't work and quickly burn out the laser, too weak or too little power and it will fail to read discs properly. There is no home position except it retracts to it's starting position on the glider the mechanism motor connected to. 

 

TOC errors can also be fixed by either a low-level firmware update to the servo board or a re-capping a  failed cap on the servo board. IC's that store buffered memory can also get corrupt over time on the servo board and need to be wiped or replaced.

 

If the player is using a CD ROM drive using a conventional pc PATA(IDE) interface as connection, rip it out and install another CD ROM driver in (or DVD ROM/drive).

Edited April 24, 2015 by DefQon

[Dwizzle]

Thanks for that DefQon, all good information.  I think I might take it in and get it repaired professionally and hopefully it won't cost too much.

Of course I had to start googling and in case I needed a replacement and saw that Musical Fidelity are making a half width CD transport (M1CD) which looks pretty cool.  How do I resist, should I be resisting.

[Equaliser]

Yeh repairing cd/dvd transports is a finicky process which requires the right tools. I`ve got over 5k retail worth of stuff that cannot be repaired. It hurts looking at something that use to work only now it doesnt.