Connect with us

Sony CDP-C335 carousel doesn't align with clamping assembly.

Discussion in 'Electronic Repair' started by David Farber, Nov 10, 2012.

Scroll to continue with content
  1. David Farber

    David Farber Guest

    This Sony CDP-C335 is just a few millimeters away from working properly.
    When the 5 disk carousel rotates the CD into place, the clamping mechanism
    closes but the metal pin in the clamping mechanism which is supposed to line
    up with the hole in the carousel is not lining up properly. It either makes
    a loud snapping noise as the pin forces its way through the hole in the
    carousel or the clamping mechanism jams completely as it cannot force its
    way into place since the alignment between the two is off. The belt in the
    carousel mechanism has good tension and is not slipping. Anyone seen this
    problem before?

    Thanks for your reply.
     
  2. David Farber

    David Farber Guest

    From what I can tell, there are some optical sensors that monitor the
    position of the carousel. So removing the carousel and then repositioning it
    shouldn't really matter. When I removed the carousel to inspect the belt, I
    reinstalled it so it was centered. I'm wondering since it's always hitting
    the trailing edge of the hole, perhaps the carousel isn't braking soon
    enough after the uP turns off the carousel motor?

    Thanks for your reply.
     
  3. I think I would look at the flat wire from the carousel down to the main
    board. Seen a few bad, and the opto-sensing would certainly be affected by
    this.

    Mark Z.
     
  4. David Farber

    David Farber Guest

    Hi Mark,

    The flat wire checks ok. I've looked around this area and the only
    suspicious thing I've found is that the carousel has a lot of loose travel
    in it when it's at rest. I measured about 2.5mm of wiggle room at the
    circumference of the carousel. That's plenty of error to cause problems. I
    think the intermediate gear between the worm gear and the carousel is worn
    out. It's location #66 on the parts blowup on page 22 of the service manual
    here:
    http://www.electronica.ro/service_manuals/sony/compact_disk_player/cdp-c335/

    Thanks for your reply.
     
  5. Guest

    This problem is usually 1 of 2 things.

    1) The gears are outof timing by 1 tooth.
    2) The green flat cable that goes fro the deck to the board is defective. This won't be visible as the connections are intermittant. Replace the cable first. This may resolve the problem.

    Dan
     
  6. David Farber

    David Farber Guest

    Hi Dan,

    The position of the carousel is controlled by the photo transistors. When
    the slits underneath the carousel line up in whatever formation the uP is
    looking for, the carousel motor stops turning. When the unit is powered up
    from an unplugged condition, the carousel spins and orients itself so that
    disk 1 is facing the user. In that respect, it doesn't matter what position
    the carousel is in when the unit is powered up, it can figure out where each
    disk is and how far to spin the carousel. I don't understand how a defective
    cable could cause the carousel to be misaligned by a couple of millimeters.
    Don't you think it would totally lose track of its position if the cable
    were bad?

    So taking that all into consideration, I took some needle nose pliers and
    slightly tweaked the metal pin that was misaligned with the hole in the
    carousel. Now it fits just fine when the cam elevates the play mechanism
    into position.

    Thanks for your reply.
     
  7. Guest

    The cable I described developes cracks with age. This causes intermittant connections withint hte cable. I have repaired a number of these units, some of which had the problem you described. Some of these also were "fixed" by replacing the cable. The cable is by no means the only cause of hte problem you describe. The photo trnasistors can be bad, the digital transistors (DTC) that "digitize" the transition can be faulty as well. The bottom line here is that there are many potential causes of the problem. Experience will provide you with clues (as I and others posted here).

    A cam gear off by 1 tooth can cause this problem as well. Obtain the service manual which contains the alignment marks to verify proper alignment of the tray as well.

    Dan
     
  8. So taking that all into consideration, I took some needle nose pliers and
    I say -- without sarcasm -- that it's gratifying when common sense works.
    (It so rarely does when servicing electronic equipment.)

    The reason this wasn't solved sooner was that there was no obvious /reason/
    why the pin should have been misaligned in the first place. How /could/ it
    have gotten misaligned?

    I had a similar problem 40 years ago. I pulled out my Nikon F and discovered
    the film advance was jammed. It turned out the take-up hub had been BENT at
    the middle, as if someone had banged it with a mallet. How did it happen? I
    never learned.
     
  9. David Farber

    David Farber Guest

    Hi Dan,

    I'll recheck the timing again. Though I don't understand what the timing of
    the cam that closes and opens the drawer and raises and lowers the play
    mechanism has to do with the positioning of the carousel. I've worked on
    enough of these carousel players to know that when the timing is off by one
    tooth in one direction, the drawer closes all the way while the cam is still
    continuing to try and push it even further. As a result, the cam gets jammed
    and that's the end of that loading cycle. If it's off by one tooth in the
    other direction, the clamping assembly will bite down on the disk before
    it's pushed all the way to the back of the mechanism. Neither of these
    faults has anything to do with the rotation of the carousel as far as I can
    tell.
    Also, I'll try and find a way to put a scope probe on the photo transistors
    and see if there's a clean signal coming off of there.

    Thanks for your reply.
     
  10. David Farber

    David Farber Guest

    The pin probably wasn't misaligned in the CD player. Anywhere along the line
    there could have been something that was warped. But the easiest way to
    correct it was to just tweak the pin.

    By the way, that Nikon F is a sweet camera. (-:


    Thanks for your reply.
     
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day

-