Cdx-720

Hi.
I picked up a Yamaha CDX720 a while back for $5 .
Just getting around to using it and it has a few bugs.Mainly it dosent track well ,goes of on its own tangent .But when it plays and it does its a great CD player.

Taking the lid of. I mess with the pots ..no change. However if I take my screw driver and apply pressure to the clamp that holds the CD to the drive motor. It will play flawlessly. remove the pressure and its off on its own merry way.
So Ive deduced that it maybe a focus issue .
Ive watched the lens as it aquires a new CD and it does stutter a bit. no matter what I do.
I removed the lens head from the player and noticed again that there are two pots on it.Im assuming these are factory set.

Theres a lack of info on this player. Before even messing with the pots I noticed that there are terminals ,again Im assuming , for a computer interface to dial the head in, probably using a specific Yamaha test CD.

For 5bucks I had nothing to lose by running amuck, considering I was going to first break it down for parts,untill I noticed the Yamaha DACs and various IC's.

Everything else plays and does what it should, given I have to use constant pressure to get this thing to play.I really think its a focus issue , at best the drive motor governor is wacky.
This CD player kicks my Techniques MASH butt down the street and back.
Any info appreciated. New heads are still not hard to find. Unless theres something else Im missing

This is a disc spindle motor problem, bearings have gone dry. Under warranty, we used to just replace the disc spindle motor. But you might be able to salvage the motor by applying a drop of light weight oil against the motor shaft under the spindle plater and let it run down into the bearing. I've done this with hundreds of units out of warranty and it usually helps.

Thank you!!!

I will give that a go .

3n1 oil?

No matter I have a light weight oil here somewhere. had a precision oiler once.. "had" being the operative term.

definite improvement:thmbsp:

just have to get the pots all dialed in.

I made a mess of her.:thumbsdn:

Well it plays ,much better.
Dosent seem to like ZZ-Top, or Metallica

likes

Van Halen ,Joe Satriani ,Megadeth and Steve Earl.

I have heard of older players not liking some disc ,ironically the unit played burnt CD I did about 10yrs ago.

Might be a firmware issue, or Ive made a good mess of the pot's and the setup. Service manual would be nice .
Also ,would this unit have any onboard diagnostic menu that can be accessed.

Still ,she's a totally different player now after a little lubrication.