Rotel RCD 961 'no disk'

[John10]

Hi everyone. I hope someone can help me out here. My Rotel RCD 961 was working fine up until about a week ago. Now when I load a CD the display says 'no disk'. I tried several different CD's with the same results, so I opened the case to observe what was going on and found this: When I load a CD it spins about a quarter turn, and the laser pops up and down. It does this three times in a row, stops, and then displays 'no disk'. I noticed that the laser does not emit any sort of light so I replaced it with a new one (KSS 213C) but this did not fix the problem. Does anyone have an idea as to what may be causing this? Any suggestions would be greatly appretiated. Thanks-John

 

[johnnyx]

The head moves up and down trying to focus on the disc. If, after three goes, it hasn't found the focus, it reports " no disc".
You could try cleaning the lens - carefully - and see if that cures it.

 

[John10]

I thought that may have been the problem and I did attempt to clean the lens but this did not help. I even replaced the laser pick-up with a new one and this did not work either. Should the disc be spinning at full speed while the laser is trying to focus? It only spins about a haf turn or so.

 

[Frazzled]

hmmmmmm

Yup, I think every cd transport I have ever looked at spins the cd while the laser is focusing. Now as far as figuring out why yours isn't, that my friend is quite a different story.

I had an old player that wouldn't spin the cd but it was because the player had gone unused for a long time and the belt hardened in place, I suspect that your Rotel is direct drive as are most now.

 

[John10]

It does appear to be direct drive. Does anyone know if the motor is controlled by some sort of microprocessor? A friend told me that there was a brown-out /power surge in our neihborhood the day that it stopped working.

 

[li_gangyi]

if your transport is new...it might have some solder shorting out some connections on the ribbon cable area...check to see if you have removed it...

 

[John10]

I've read that some new laser pick-ups have a solder bridge placed across the laser diode to protect it from ESD during shipping and installation. Does anyone know what this looks like ? Is it just a blob of solder that you remove after installation? It's a sony KSS 213c.

 

[li_gangyi]

it's usually just a blob of solder across 2 connections on the ribbon cable or the laser PCB...

 

[John10]

Well, I fixed it but I'm not exactly sure how. I do know that the laser pickup was not working (no IF emission) so it was unable to establish focus. After temporarily reconnecting the old pickup to the ribbon cable the laser suddenly began to work so I just swapped it back in and now everything seems to work fine. I suspect that the ribbon cable may not have been seated correctly in it's socket. BTW, using a video camera (CCD type) is a pretty good way to test for IF emission of the laser pickup.