[long] Help!!! CD spinning sloooow

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Hi all,
just after reading a lot on jumping CD, it's my turn now (sadly)...

A couple of evening ago, while trying to attach to a wall a decorative
photo given by my wife, I accidentally pushed the test switch on the
general switch located on distributor mains, while music was playing...
(a CD was playing, indeed).

Then, definitely not smart at all, I pushed it again in order to light
all the house on.

Ok, I came back to my music and, after a while I seemed a CD was
"plopping", I listened to small "pop, plip" and "plop" in music flow. I
swapped the CD, yet the problem persisted... more some CD started
randomly refusing spinning when inserted.

I disconnected the player, opened it and tried to understand something
more... it seemed the motor metal spindle lacks some torque when trying
to spinning CD (the whole mechanics is based on a 2 metal rails unit,
laser is a SANYO numbered N0503705).

I added a gummy ring, to help spindle grip the CDs, but it didn't solve
the problem. More, when the CD plays I slowed further more the CD with a
finger, the problems heard, seems of same nature: some clicks and pops
which are louder and more distinguishable as the slowing increases.

So, I thought the problem is rotational constance of the motor. Is it
ok? Is it possible to fix it?

Below a list of IC and pots seen on the digital/control board:
IC: Sanyo LC6538D 1L1 4814

pots:
P002 E/F BAL 103
P001 T.DC-OFF 104
P003 T-GAIN 502
P005 F-GAIN 203
P007 FREE RUN 204

Is perhaps worth trying to adjust some pot, if anything changed in
electrical characteristics of CD player (perhaps due to current inrush),
or better to look for another mechanics, or replacing the only motor is
feasible???

Sorry for LONG LONG post...

TIA,

Stefano
 
...followup...

Thanks a lot for replying Hjelm,
yesterday evening I kept on listening to it apparently w/o popping problems.

So, I argue that motor is ok. By carefully inspecting boards while looking for burning signs, I found a small electrolytic cap, 10uF/16V Rubycon, with a small opaque shade on top.

Every other cap seem bright, only this one shows this small area (do you know on the silver color (I guess Alu) circular area top of electrolytics).

The cap is located quite near the Sanyo controller chip.

Do you think that replacing it would be a possible solution?

How is it possible that yesterday the player kept on playing correctly several CDs, even when subsequently powered on and off???

Thanks for replying,

Stefano
 
Reapplying power gave a power surge to the CDP.(That's why you should unplug computer, TV... before applying power) I got a CD player that was doing the same thing, I took an older revision drive and it was OK.

I think the pickup was to it's end, but I wasn't using the other player(That used a better pickup).

Thing I cannot understand is why yesterday the popping effect was not there...
Try playing it for about 2 hours, if it restarts, the pickup that might have been over-powered.(My CDP was doing this)

Or the cap maybe had over-volted and restabilized. Change it since it looks damaged.
 
well yesterday evening the player sounded correctly for 2-3 hours, I changed CDs and pieces w/no problems.

I'll look for a good 10uF 16v electrolytic cap to replace anyway the shaded one.

In this case is a swap with a higher voltage cap presumably a better (safer) option???

Ciao and thanks for your kind feedback,

Stefano
 
popping again

Hi hjelm, Dragonmaster,
after a whole day of correct sound (really good after putting some bubblewrap and a slate under the cdp), the popping effect re-appeared this morning on the CDP (perhaps a whole day playing cooked the "shaded" cap inside?)...

It happens I don't have the 10uF cap around, I have some 22uF/25v and 100uF/50v. Do you think that using a different (higher cap) might be ok, as the cap quite near the motor controller unit might be a sort of reservoir for the IC SANYO controlling it, or is better to replace with same capacitance (and higher voltage, this for sure)?

Thanks for your help.

Ciao,

Stefano
 
I don't know if you can put higher value caps, since some players don't like that.

Problems with caps(even once dead) are intermittent.

Sure, put higher voltage caps! I had to replace 17 of them on my cheap mainboard because half of them leaked and the other half were about to do the same things(When the cap's back is starting to get out of the rest). Bought some new ones, and my surplus shop has tons of Sanyo (Oscon? Don't know, green labeling) I bought cheap.
 
As I see it replacing capacitors are generally safe even if you increase or decrease size somewhat. The times you might get into trouble is around voltage regulators and fast circuits, opamps and the likes.
Going from 10uF to 22uF should be safe, but I am reluctant to say do it since I do not know the circuitry around it.
 
Hi Dragonmaster, hi Hjelm,
first of all thanks a lot for your kind support!

The problem is definitely intermittent (yesterday evening the cdp played good), so I really hope this is related to that cap which is near the controller of the reading.

I've ordered some 10uF/25v Rubycon which should be better than the 10uF/16v (always Rubycon) actually in use.

I'm sorry not to be able to share the cdp technical details, I looked for them but couldn't find. Player is Audiomeca Obsession (Mk I), anyway.

Should you have any further suggestion, you're welcome!

Ciao,

Stefano
 
Hi,
not willing to abuse of your patience, but sadly the pop problem is again here, even with classic... ;) :xeye:

I opened the player again (Audiomeca Obsession mk I), the aforementioned cap seems covered by a slight film of protective glue or whatever, doesn't seem burned.

But my finger was almost burnt by a IC near the motor control unit, it has a heatsink, but it runs very very hot. Might that be a sign of burnt motor controller?

I'm stuck as it seems quite hard to find schemas for this player...

Thanks a lot,

Stefano
 
Maybe it is a driver circuit for the motor. Do check that it is not fried and has a short circuit. Also check the motor if it seems healthy. Do you have an oscilloscope at hand?

Does the circuit have any label you could search for it and see what it is supposed to do.
 
But my finger was almost burnt by a IC near the motor control unit, it has a heatsink, but it runs very very hot. Might that be a sign of burnt motor controller?

Often, they just use the lowest rated components in the PSU so it might heat a lot. I have a regulator in a Sony CDP that runs REALLY hot too.(But we're not talking about the same player at all). It's like when I uncorrectly soldered my 2x40 LCD panel. The ICs on the back started burning me <2 secs after it was plugged.

For shorts : If the mentioned IC turns hot really fast after power on, then there might be a problem.
 
Hi friends (I hope I can dare to consider you my friends),
yesterday evening I was tired and could only mark the hot IC name: LA6524 - 2L4.

The LA6524 seems to be a power driver for the CD splindle.

www.alldatasheet.com/datasheet-pdf/pdf/SANYO/LA6524.html

It's made by Sanyo (as any other IC piece I could recognize on the Audiomeca).

That's all for now. How could I check motor integrity with my tester/oscilloscope (I've never tested a motor...., sorry for my dummy questions) ?

Stefano
 

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