Vintage CD Player woes .. need to pick the brains of the techies in the house.

[GotHifi]

It had to be tried

I'd probably go down the route of using freezer spray (very sparingly) now.

It's already been done with no results.

 

[GotHifi]

If you tap gently on the case while a disc is playing, does the player skip?

Nope, tapped, turned sideways, no issues. Mind you, its a solid cast metal machine, I would probably have to punch it lol.

 

[GotHifi]

An oscilloscope is pretty much mandatory for all fault finding on things like this

don't have one, and wouldn't know what to do with it if I did. Kinda why I made this post looking for others who may have ran into a similar issue and corrected it.

 

[Extreme_Boky]

I have a CD player (B&O CDX) that once turned on, has to sit for 5 - 10 mins before it can be played. The strange thing is how it tells you when it's ready to be played. I press power, don't touch anything else and just let it sit .. 5 or so mins later, it will emit a loud static out of the speakers, which will then slowly taper off over about a minute. After this, I can play the CD no problem (with a bit of static here and there). If I try to play a CD before that, it will just sound distorted until that same 5 or so minutes passes, then the sound clears.

I'd look along the path of digital sound reproduction.

The SAA chips are known to fail; the fault description points to digital RF audio stream handling issue. check the two polystyrene capacitors, 3 transistors and the SAA7010 located close to that white trimpot and white labels... You need a schematics and an oscilloscope for this.

Polystyrene caps can start to short if mistreated (close proximity to heat from the soldering iron, mechanical stress...)

The 1540s are most likely okay because both channels are affected the same way, at the same time.

Good luck

 

[Mooly]

It's already been done with no results.

No quick or easy answers in that case It turns now into a proper fault finding exercise which needs a very methodical approach and the correct test equipment (a good scope at the very least) I'm afraid.

 

[sgrossklass]

OK, so how many electrolytics are left that haven't been changed, however hidden they might be? When stuff starts working after warmup, 99.9% it's some electrolytic. Maybe a bad solder joint.

 

[GotHifi]

I'd look along the path of digital sound reproduction.

The SAA chips are known to fail; the fault description points to digital RF audio stream handling issue. check the two polystyrene capacitors, 3 transistors and the SAA7010 located close to that white trimpot and white labels... You need a schematics and an oscilloscope for this.

Polystyrene caps can start to short if mistreated (close proximity to heat from the soldering iron, mechanical stress...)

The 1540s are most likely okay because both channels are affected the same way, at the same time.

Good luck

Just replaced the SAA7010 and resoldered transistors. No change.

 

[GotHifi]

OK, so how many electrolytics are left that haven't been changed, however hidden they might be? When stuff starts working after warmup, 99.9% it's some electrolytic. Maybe a bad solder joint.

Every single one of them except for the one on the lid control motor have been changed.

 

[Extreme_Boky]

Just replaced the SAA7010 and resoldered transistors. No change.

... You need a schematics and an oscilloscope for this.

Good luck

You really have two options:

1. continue replacing parts, one by one - which still does not mean the ultimate success (there might be a cold solder joint somewhere, or a tiny PCB track crack - these are difficult to spot...)
2. Get the oscilloscope and the schematic with waveforms, and then start from the ingress point from the CD mechanism, and then work forward.

 

[GotHifi]

You really have two options:

1. continue replacing parts, one by one - which still does not mean the ultimate success (there might be a cold solder joint somewhere, or a tiny PCB track crack - these are difficult to spot...)
2. Get the oscilloscope and the schematic with waveforms, and then start from the ingress point from the CD mechanism, and then work forward.

I do have the schematic and I have inspected the PCBs which appear to be in good shape, there is one lifted track, but still connected. Replacing parts is OK by me as all the parts I paid for (caps, reeds) needed changed anyways. The rest of the parts are coming from a second CDX I have that doesn't read discs. Hopefully I will get lucky and find the part causing this and be able to replace it from that machine. I do not have access to an oscilloscope.

 

[Mooly]

I still think you should pursue the freezer/heat theory. Why not try heating a small section of board at a time (with a hairdryer) and see if it starts working immediately.

 

[GotHifi]

I still think you should pursue the freezer/heat theory. Why not try heating a small section of board at a time (with a hairdryer) and see if it starts working immediately.

Due to the top loading design, the only board that can be accessed while this machine is running, is the decoder board. I have done the freeze spray on it, however, I have not tried heating it. I will give this a try as I do suspect the issue is on this board.