MD/CD deck repair

[reb78]

I have a number of HiFi decks. One that I bought about 25 years ago is an MD/CD combined deck. MD still works perfectly. The CD side doesnt work. You put a CD in and it makes an odd whirring noise and then error as it wont read the CD.

What fails on a CD player and are repairs expensive? I hardly have any CDs now but it bugs me it doesnt work!

 

[Bullet2012]

You need to rewind the discs, with one of these !

 

[bricol]

Could be as simply as a broken belt?

The internet might be your friend.
My JVC hifi would play some CDs, play some CDs after multiple attempts, and not play others at all. Some interneting revealed another JVC model witj similar issues - all to do with the bit that reads the cd - needed a couple of potentiometers tweaking to increase its oomph - or some such technical term. Obviously its needs doing properly so you don't over do it, or adjust the wrong thing.

So as I couldn't find anything specific to mine, I found what I though were the right ones, marked their position, and tweaked one a bit.

Now plays any CD I put in it. I have no idea if its over-done, about to burst into flames, melt CDs, causes aircraft flying overhead to suffer interference, or the baby monitor next door now doesn't work . . .

 

[AKN]

The laser diode that reads the disk ages and loses output. They can be replaced, you need an alignment disk and a fast oscilloscope, or a lot of luck.

 

[Wozzaaah]

I have a number of HiFi decks. One that I bought about 25 years ago is an MD/CD combined deck. MD still works perfectly. The CD side doesnt work. You put a CD in and it makes an odd whirring noise and then error as it wont read the CD.

What fails on a CD player and are repairs expensive? I hardly have any CDs now but it bugs me it doesnt work!

I would guess the belt/s have probably perished and/or turned to goo. You should be able to get a suitable replacement but there will be some major disassembly required to fit it. You have nothing to lose though.

 

[Wozzaaah]

Has it been sat unused for a long time or has it been in constant use and suddenly failed? The first thing to do is take the cover off to expose the mechanism, insert a disc and see what’s going on (or not, as the case may be).

 

[reb78]

Has it been sat unused for a long time or has it been in constant use and suddenly failed? The first thing to do is take the cover off to expose the mechanism, insert a disc and see what’s going on (or not, as the case may be).

It doesnt get a lot of use these days. I use the record player a lot more. But every now and then I want to listen to a CD and its a shame it doesnt work when I do want it.

I will see if I can get it apart and what i can see when i have. I dont want to ruin the MD part of it in the process as rather weirdly, I have more MDs than CDs these days!

 

[Chippie]

The laser diode that reads the disk ages and loses output. They can be replaced, you need an alignment disk and a fast oscilloscope, or a lot of luck.

Yes they do age and lose their optical abilities…There used to be a supplier called Grandata who would supply laser assemblies for various makes, not sure if they are still on the go…( seemingly not, I checked just now..)I used them for spares when I was in the telly repair game…

 

[Chippie]

Wrong speed?

The speed at which the disc turns isn’t constant, it varies depending on where the laser is reading the data from…

 

[Seadog]

EBay is usually a good source of laser modules.

 

[reb78]

Is there a diy way to know if the laser is at fault?

 

[jmp49]

Chippie has it. I would err on it being needed for the laser head replacement.
I often deal with repairing old game consoles that use cd's and when you put a disc in, the unit spins the cd and uses the read head to know its spinning at the correct speed and present. Its quite common to hear them spin up multiple times and then fail, or get sync at the 4th or 5th try with the disc spinning up to speed for each try. Sometimes you can clean the lens and they work, but this is rare, and mostly its replacement needed.
I replace the laser module as a complete unit, its bespoke to each one but because there's a niche market covering parts for them its not hard for consoles & a new laser module usually costs around 30-50 quid which given some of them change hands for hundreds of pounds to retro enthusiasts in fully working condition (cd32, 3DO etc) its worth investing in.
Probably if your really dedicated you could get the exact part number of the laser unit itself and try to find someone selling new ones.
For a hifi unit, I'd try the cleaning cd's you can get, or scrub the lens with some cardboard gently or your other preferred method and if that fails, I'd just get another player...

All my old cd's from back in the day are unplayable due to corrosion, if you look at them under a lamp you can see pinholes or scratches so make sure the cd your putting in isnt the source of the problem too. Fortunately I mp3'd them all when I got my first pc and I still have the files.
Its also funny that to me the best mod to a cd era console you can do is usually to add some kind of hard disc or network connection to store all the games on so you don't have to deal with swapping cd's and media scratches, but some people like their nostalgia pure & the full thrash themselves with birch twigs in frustration purity experience. Me? even my 2600 has a wifi flash cart in

 

[reb78]

Chippie has it. I would err on it being needed for the laser head replacement.
I often deal with repairing old game consoles that use cd's and when you put a disc in, the unit spins the cd and uses the read head to know its spinning at the correct speed and present. Its quite common to hear them spin up multiple times and then fail, or get sync at the 4th or 5th try with the disc spinning up to speed for each try. Sometimes you can clean the lens and they work, but this is rare, and mostly its replacement needed.
I replace the laser module as a complete unit, its bespoke to each one but because there's a niche market covering parts for them its not hard for consoles & a new laser module usually costs around 30-50 quid which given some of them change hands for hundreds of pounds to retro enthusiasts in fully working condition (cd32, 3DO etc) its worth investing in.
Probably if your really dedicated you could get the exact part number of the laser unit itself and try to find someone selling new ones.
For a hifi unit, I'd try the cleaning cd's you can get, or scrub the lens with some cardboard gently or your other preferred method and if that fails, I'd just get another player...

All my old cd's from back in the day are unplayable due to corrosion, if you look at them under a lamp you can see pinholes or scratches so make sure the cd your putting in isnt the source of the problem too. Fortunately I mp3'd them all when I got my first pc and I still have the files.
Its also funny that to me the best mod to a cd era console you can do is usually to add some kind of hard disc or network connection to store all the games on so you don't have to deal with swapping cd's and media scratches, but some people like their nostalgia pure & the full thrash themselves with birch twigs in frustration purity experience. Me? even my 2600 has a wifi flash cart in

Useful post. Thanks.

You describe the exact symptoms it has so sounds like it is the laser unit. Cleaning helped for a time, but alas no more.

 

[bricol]

Useful post. Thanks.

You describe the exact symptoms it has so sounds like it is the laser unit. Cleaning helped for a time, but alas no more.

Cleaning with lens cleaner and cotton buds worked with mine for a time.

The pot tweak was free and so far, a few years later, still working.

 

[Chippie]

Cleaning with lens cleaner and cotton buds worked with mine for a time.

The pot tweak was free and so far, a few years later, still working.

Don’t tweak the pot too far, risk of laser or disc damage…