Sign in   |  Join   |  Help

Beosystem 2500 - laserfejl m.m.

rated by 0 users
Not Answered This post has 0 verified answers | 16 Replies | 1 Follower

Peter Andersen
Not Ranked
14 Posts
OFFLINE
Bronze Member
Peter Andersen posted on Thu, Mar 14 2019 7:30 PM

Hej alle

Jeg har et Beosystem 2500 stående der ikke vil læse CD. Den har lidt sit eget liv, laseren vipper op og ned, spindlen kører lidt rundt, og "ryster" mens den kører baglæns og kan pludselig finde på at køre på fuld drøn, dvs. meget hurtigt rundt helt ukontrolabelt. Alt sammen uden at vil læse CD'en på noget tidspunkt.

Er det dårlige lytter eller skal der en ny laser til? kan der overhoved skaffes ny laser til 2500?

Peter

All Replies

Weebyx
Top 100 Contributor
Denmark
973 Posts
OFFLINE
Bronze Member
Weebyx replied on Fri, Mar 15 2019 7:00 AM

Peter Andersen:

Hej alle

Jeg har et Beosystem 2500 stående der ikke vil læse CD. Den har lidt sit eget liv, laseren vipper op og ned, spindlen kører lidt rundt, og "ryster" mens den kører baglæns og kan pludselig finde på at køre på fuld drøn, dvs. meget hurtigt rundt helt ukontrolabelt. Alt sammen uden at vil læse CD'en på noget tidspunkt.

Er det dårlige lytter eller skal der en ny laser til? kan der overhoved skaffes ny laser til 2500?

Peter

Det kommer lidt an på hvilken laser den har. Er det den kurvede eller lige version ? Den kurvede er det sjældent laser der er problem på, men er det den lige laser, så skal du finde en ny. Det er nok en CDM 12.4 laser du skal finde, men du bliver nød til at finde ud af hvad den har først.

 

/Jacob

Peter Andersen
Not Ranked
14 Posts
OFFLINE
Bronze Member

Det er den kurvede jeg har. Den sidder under spindlen og drejer, til venstre, om sin egen aksel.

Jeg har målt lytterne efter på CD boardet, og der er ikke nogen der umiddelbart fejler noget (værdi og ESR værdi).

RaMaBo
Top 150 Contributor
near Munich
518 Posts
OFFLINE
Gold Member
RaMaBo replied on Fri, Mar 15 2019 2:55 PM

Hi,

 

sorry to answer in english.

The Beosystem 2500 with the curved laser has the CDM 4 unit installed. So the problem is caused by the famous 'C2103' to 99%.

In the Beosystem 2500 units it's C100 on the CD Servo Motor System and Disc Detector Board. replacing the electrolytic capacitor with a new Philips / Vishay blue capacitor and the fault should be gone.  C100 is connected to Pin 17 of the TDA 8808T and ground  in the '2A' area of the board.

Maybe Dillen (Martin) can provide a capacitor for you.

Ralph-Marcus

Peter Andersen
Not Ranked
14 Posts
OFFLINE
Bronze Member

Hi

 

Ok, thank you. I replaced it with a Panasonic FR capacitor, and the laserarm is steady and it seems to have cleared the problem. BUT not completely: it makes a rattle sound, turns a few times around, makes a rattle sound, and then stops.
Look here:

https://www.youtube.com/watch?v=rZv_xO8JWBM

Peter

RaMaBo
Top 150 Contributor
near Munich
518 Posts
OFFLINE
Gold Member
RaMaBo replied on Fri, Mar 15 2019 8:19 PM

That rattling sound is most probably caused by the laser diode itself, when trying to get the focus.

Every CD drive works as follows:

-move laser unit to innermost position.

- is CD installed? Switch laser on and see if it gets reflected.

- If reflection is found, spin the CD

- now try to get a focus on the surface of the CD. (This is done by moving it up and down)

-If focus found move to position of TOC ( Table Of Content) and read the table.

-play first track if not otherwise specified. position of tracks is contained in the TOC..

 

So i think it still doesn't get the correct smoothed and filtered current for the laser diode. Try to get an original Philips / Vishay capacitor.

Up to now noone ever found out what is so special about this capacitor from the manufacturerUnsure Atleast no one ever told the secret.

Make a search here on the forum 'Workshop' about 'C2103' or 'Vishay'. Nearly all problems are fixed by using a blue Vishay cap. ( https://forum.beoworld.org/search/SearchResults.aspx?q=Vishay&o=Relevance )

 

Ralph-Marcus

Peter Andersen
Not Ranked
14 Posts
OFFLINE
Bronze Member

Hmm, it sounds very strange. I am an electronics technician, and the Panasonic FR is the best quality 105° low-esr capacitor you can get. The original cap. is a low quality SAMHWA capacitor like almost the rest of the caps in the unit. It is not a Philips cap.

The problem must be related to something else, or a bad laser? I can see that the sound is a mechanical problem cumming from the spindel/cd and is not related to the laser. It makes the same sound when i turn the CD around with my finger.

RaMaBo
Top 150 Contributor
near Munich
518 Posts
OFFLINE
Gold Member
RaMaBo replied on Fri, Mar 15 2019 10:54 PM

Those 'old' radial drives are built like rock. As long as you don't play around with the laser current they work flawless and the laser itself lasts nearly forever.

See here what user Dillen (Martin) wrote about the capacitor:  https://forum.beoworld.org/forums/p/4108/36493.aspx#36493

Here's a little 'dispute ' about the capacitor  https://forum.beoworld.org/forums/p/35846/266550.aspx#266550  between Dillen and Menahem Yachad. Both are very experienced tecnicians.

Menahem uses quite often Panasonic FM for the 'C2103' (or C100 in this case).

 

Ralph-Marcus

Peter Andersen
Not Ranked
14 Posts
OFFLINE
Bronze Member

Ok, great. The FR and FM are the same capacitor, FM are just for only 2000-7000hours where FR are for 5000-10.000hours.

But anyway, it it not that problem i have here. The spindels runs backwards at full speed. I also notised that the trimmer was turned full CW (as seen from the solderside) - pretty strange.

I think I have to get Martin to look at it.

Dillen
Top 10 Contributor
Copenhagen / Denmark
10,732 Posts
OFFLINE
Founder
Moderator
Dillen replied on Sat, Mar 16 2019 12:39 PM

I wish people would stop focusing on low-ESR. It's as if low-ESR is the best thing in the world.
It's not.
In some circuits using low-ESR will be fine but definitely not in general.
In some circuits, like f.e. DC-coupled output stages with a certain amount of feedback, they can really mess things up and
cause self-oscillation, ending in heat and smoke and elaborate repairs.

Use a blue Philips/BC capacitor and forget about the "trendy" Pana-stuff. Works every time.
(And the talk on other fora about it affecting the sound quality is rubbish).

Martin

Peter Andersen
Not Ranked
14 Posts
OFFLINE
Bronze Member

Yes, I know. It is designet for SMPS, and I have only them in stock so I use them for everything. Can't get better quality, no reason to have other types. If you experience problems with them, then you have a poorly designed circuit. And for audio: the real audio grade capacitors are the same as the Panasonic F-types, a high quality, low-esr capacitor made with same build method. It is just a high quality cap, then they brand it as audio cap. No difference in general. For filters, its another matter. An for sundquality: yes, the quality of a capacitor has a very big impact! just try it it.

If you really mean that replacing the capacitor to a Philips would solve the problem - then I would like to buy a couple of them from you. I just don't understand why it was equipped with a SAMHWA capacitor from the beginning if the Philips was the only correct one. (no it has not been replaced, it was original).

Peter

Peter Andersen
Not Ranked
14 Posts
OFFLINE
Bronze Member

Jeg har lige fundet ud af at den spiller fint hvis den ligger ned, dvs. hvis hele anlægget ligger på ryggen eller blot er vippet 45grader baglæns. Men står det op lodret - ja jå "raller". Sært. Der må være en mekanisk ustabilitet i det tænker jeg.

C100 er prøvet skiftet, men det ændrede intet.

Peter

Dillen
Top 10 Contributor
Copenhagen / Denmark
10,732 Posts
OFFLINE
Founder
Moderator
Dillen replied on Sun, Mar 17 2019 7:52 AM

Peter Andersen:

Yes, I know. It is designet for SMPS, and I have only them in stock so I use them for everything. Can't get better quality, no reason to have other types. If you experience problems with them, then you have a poorly designed circuit.

Not as a general rule.
Some circuits were simply not built for low-ESR capacitors. It has nothing to do with poor design. B&Os DC-coupled amplifiers are excellent designs.

Peter Andersen:

And for audio: the real audio grade capacitors are the same as the Panasonic F-types, a high quality, low-esr capacitor made with same build method. It is just a high quality cap, then they brand it as audio cap. No difference in general. For filters, its another matter. An for sundquality: yes, the quality of a capacitor has a very big impact! just try it it.

In the case of C2103, sound quality and audio grade is irrelevant. Fitting a low-ESR capacitor for C2103 won't improve anything, the
CD player won't seek faster or play the slightest bit better. (Regardless of the fact, that nothing but a Philips/BC can be guaranteed to work in this postition).
Did you read the discussion threads that was linked to above?

 

Peter Andersen:

If you really mean that replacing the capacitor to a Philips would solve the problem - then I would like to buy a couple of them from you. I just don't understand why it was equipped with a SAMHWA capacitor from the beginning if the Philips was the only correct one. (no it has not been replaced, it was original).

Peter

A Samwha capacitor was never original as C2103. They are all Philips.
Are you sure, you are looking at C2103?
What type of drive and servo board is yours?
Any chance of a photo or two?

Martin

Peter Andersen
Not Ranked
14 Posts
OFFLINE
Bronze Member

Taler vi om C100 eller C2103 - nu er jeg nemlig forvirret fordi der bliver talt om C100 og C2103 fra flere forskellige sider.

C100 som er DC stabiliseringen til laseren, den er en Samwhakondensator på 47uF - og den ER original. Garanteret 100%, der har ikke været pillet i det her anlæg overhoved og det er den originale bølgelodning der stadig er over det hele.

Peter

Dillen
Top 10 Contributor
Copenhagen / Denmark
10,732 Posts
OFFLINE
Founder
Moderator
Dillen replied on Sun, Mar 17 2019 2:07 PM

What type of drive and servo board is yours?
Any chance of a photo or two?

Martin

Page 1 of 2 (17 items) 1 2 Next > | RSS
Beoworld Security Certificate

SSL