Stuck Sony minidisc/s

[Mooly]

Originally Posted by ITAM805

Looks sealed to me but no experience with these?

Same for me but I think I see how it works now.

The push to make switch is simply another contact on that resistor chain... remember the early VCR's and the cable remotes they had. They were the same, a different resistor value switched into circuit produced a different function. It would just change the voltage read by a chip that interprets the commands.

The other pins on the encoder produce a pulse and the uP will look at which one (pulse) occurs first to determine which way you are turning it. It will just be a wiping contact in the encoder, nothing more sophisticated than that.

Get it pulled apart...

[ITAM805]

OK, I got the encoder apart and think I found the problem, the disc isn't rotating with the shaft. Unsure whether to try and weld it with the soldering iron or superglue, there's not much room in there?

[ITAM805]

I'll be jiggered, it works! I realised that the little disc is locked in place under pressure of the spring when reassembled, so no glue required.

I though I had it up as the tiny gold plated prongs got mangled as I was trying to put it back together, but the fixing gods were in a forgiving mood today. A fiddly job but worth trying - but easy to screw up if your not careful

Thanks to Christopher and Mooly for the advice and encouragement

[Welsh Anorak]

I wasn't so lucky with one that had been well and truly mangled. I managed to find a similar replacement (Sony said no). It worked fine - but backwards!

[Mooly]

Originally Posted by ITAM805

I'll be jiggered, it works!

Brilliant, well done. Lol, and I know what's inside one now.

Wonder if it has had a whack or something at some point.

[John M1JWR]

Originally Posted by Mooly

Wonder if it has had a whack or something at some point.

Could be correct there, I've had that with two 470's, they are the same as 480 in that area, also look out for one function working and another not, that may be a hairline through a track, easy to check for as there aren't many tracks.

[BristolBillyBob]

Originally Posted by John M1JWR

bit late on this and i havent read all of it, to get the discs out its quite easy on the mdm7 drives, at the back of the drive you will see two white parts a broader one and a narrower one, firstly give the broad one a wee push about half an inch just until it stops dont force it, that one lifts the disc out of play position, then you can push the narrow one until the disc comes all the way out, then you can remove the disc, replace belt through the front using good tweezers and re install drive unit and all should be good again, when a md deck is stuck in standby its because the eject belt is on its last legs and its tried to eject gone a little bit and disc is in no mans land and player dosent know what to do so wont switch on, the traditional way of replaceing the belt is fraught with risks, that way you detach a small spring on the side and move the clip at the back, and the top part slides to one side and lifts off so belt can be replaced from the top, two big problems that way you can loos the spring or worse break the clip at the back and the you are foobared, thats why i go through the front method, easy peasy, one other thing and if its incase anybody gets c13, its not always the laser, as md decks were a flash in the pan years ago they were used for a short time and then put away so sometimes cleaning the contacts on the two ribbon cables can cure it as they can condense with time, done loads of them, fairly reliable is minidisc unlike the other one, dat !!
sony insider is where you need to read, cant post on there just now something wrong with the site.

Hi!

I registered just to thank you for your post on this thread.

I fired up my old minidisc player and foolishly put in a disc of music I wrote and recorded 25 years ago - and the only copy of it! - only to find it got trapped in the mechanism and I couldn't get it out! Needless to say, I was horrified! But then I found your post here and your pointers helped me free it safely, so I'm very glad of your help.

Upshot is (like most Sony MD decks it seems) it likely needs a new belt for the mechanism, so I'm going to try and repair the player... I promise to use a more disposable disc to test it next time!

Thanks for the post, very much appreciated.