Bos00 wrote:

PCB inside damaged and "repaired" Login to view image

This is usually a sign of a repairer that doesn't know a bit about what he is doing - why jumper the broken tracks back in? The 3 cm of copper track in the loose corner doesn't have any magic qualities, just skip it entirely with a single jumper wire... (and relocate the single component / jumper wire that actually was connected on it)

I wouldn't worry about any caps or other component failures at this point, it is obvious that you will find a lot of connection problems to solve first.

Most common problem and solution. Replace the laser.

Costs about 10-15 euro max.

Done several with the same symptom, replaced the laser and worked again. You can find them easily at ebay.

Ordered a few lasers CDM12 last week. Think I'm gonna place a thread how to replace them if anyone is interested!

A laser diode will usually not die from being dropped on the floor.
In fact, the laser diode is usually one of the most robust components in the whole machine, both physically and
electronically, and it's very rare to see a burned out laser diode. It's almost always something else causing it not to work.
I'm not saying that it cannot happen, just that it's rare to see.
I've replaced only two or three in my time, at least one of them was due to mechanical abuse from a "repairer" trying
to make the laser focus by grabbing and forcing it with pliers...

That PCB corner; I'm afraid I must agree with Mika. It does seem to hold a single component or something else
on the other side, but a repair involving a fresh set of leads across the entire broken area would have been
a much nicer repair. What you've done may work now but vibrations etc. will eventually cause it to break
and develop intermittent problems, no doubt.
If the corner has a supporting point, glue it back onto the rest using araldite and then pull new leads across the whole
broken area. Three leads in this case, it seems, unless more is broken.
If it doesn't hold a supporting point, throw the lose corner away.
Still, I cannot help thinking that lots of components will have become hurt in some way or another from the drop.
Generally, physical blows like this is a no-go for almost any PCB.
ICs can end up with internal "scars" to the junctions connecting the pins with the dye chip, something that
will show up sooner or later.
SMD populated boards like this are worse than conventional ones. You will never find the IC with one pin broken
away 1/1000mm from its solder pad...

Laser diodes are easy to replace. Getting the adjustments right afterwards can be a completely different matter,
particularly after a 30+G impact like this.
Still, as Mika suggested, I would concentrate elsewhere first; Power supply voltages, control signals etc.
Check the cats eye pattern, it will tell you everything!

I do like a challenge myself, long time members will know this and I have a huge respect for people who are willing
to go the extra mile but, personally, I think, I would steer clear of a unit like this.

Martin

Dillen wrote:

A laser diode will usually not die from being dropped on the floor.

It isn't said that the system worked properly before it dropped.

I repaired a BS9000 mk1 from '99 with a CDM 12.6. This system also dropped on the floor. It had some serious scratches on the alu panel and a broken glass window. After repairing that, and some capacitors in the powersupply, and a thorough cleaning of the complete system, the system didn't play cd's either. 

After replacing the pickup element, the BS did play cd's again. It is just a matter of how many hours the system has played cd's. A worn out laser is more likely with aging systems.

Agreed that you should check everything else before replacing lasers. But that's something I assume Bos00 already has done..

If the laser diode is bad, by all means replace and readjust.
It's just not the first thing, I would suspect in a situation like this.

But, hey,  we don't know if the machine was dropped by accident or tossed on purpose..

Martin

Beobuddy wrote:

After replacing the pickup element, the BS did play cd's again. It is just a matter of how many hours the system has played cd's. A worn out laser is more likely with aging systems.

There seems to be some misunderstanding - I believe the repairs I first commented on were something Bos00 found inside the machine, not ones he has made himself 🙂

Quite typical though... I'm still sore about the Beocenter 8000 I once bought with a "non-functional CD". The seller told me that nobody had tried to repair it (and so I assumed it to be the simple cap replacement). When I opened it up I found a number of detached ribbon cables, as well as some replaced caps on the servo board that weren't even soldered in(!) and the nicest suprise of all, a dead laser.

Oh, if that's the case I misunderstood it.🙁  Sorry, I'm getting old.  😂
I've mainly dealt with the older CD players, CD50, CD X etc. anyways. Their technology and playing hours
is of no match to this one, I suppose and my experience in matters B&O is limited at best.
I will pull out here and leave room for the more experienced tech'ies.

Martin