Fixing LC2 dimmer IR issue

21 replies

I change all of them...not working.

Have 5v on the IR board.

So next step is to go step by step that is why i need service manual.

I do not wist to thow it in to scrap.

 

 

I can not find online service manual.

Have somenoe form you in PDF ?

Thanks

Does the dimmer show any reaction when touching the dome?

 

If so it's the SMD capacitor which 'Frank' (the thread starter) showed in his excellent failure analysis.

I had the same fault on the IR Receiver part in a BeoLab 3500, a _non_ constant voltage at pin 3 of the AM receiver chip. Changing the buffer capacitor solved the issue, the reference voltage on pin 3 was absolutely flat and the IR receiving was fine.

 

The touch function can also be tested when the dome is removed. There's a small black rubber hose sticking through the plastic frame. it connects the dome with the corresonding circuit on the mainboard. You can touch it with your bare fingers without any harm. This rubber piece is small and necessary for the touch function, so keep an eye on it, to not loose it,

 

 

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Hi

I have 4,8V on the IR  PCB

When i pug in to 230V the light bulb 60W goes on and that is it.

Not possible to do anything more.

There is no reaction to either manual control or remote.
Maybe it's a non-working triac?

That is why i'm looking for shematics manuals.


 

problem found :)

triac not working so i need to repalace with sensitive gate triac.

it should be Igt 5-10mA

did try GT 138-600 but it only worked if warm as it's only Igt 25mA.

 

Great, get a

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hi

I purchase BT138-600E with Igt 10mA, hope it's ok :)

Thanks for tip :)

done :)

BT138-600E working just fine :)

 

Guten Tag Frank

Ich habe das gleiche Problem mit einem LCS 9000. Ich hoffe , Du kannst mir weiterhelfen: Die Frontabdeckungen sind weg , vor mir liegen die 3 Platinen 

1: ist die Deckelplatine mit dem Display -arrey drauf, da ist auch die rote Diode eingesteckt und die Infrarot.Dioden eingehackt ist der rechteckige Plastikrahmen. Ein Flachbandkabelanschluss.

2. darunter liegend links ein kleinere Platine mit drei Flachbandkabelanschluss

3.rechts davon eine quadratische (ca. 6x6 cm ) abgeschirmte Platine mit einem Flachbandkabelanschluss.

Welche der beschriebenen Platinen ist die Platine, wo ich den SMD Capacitor finden kann .

waren es 22uF / 6V ?

Besten Dank für Deine Hilfestellung

 

MFG Ueli Pfister 

Hi,

concerning the non IR receiving LCS9000 / Beolab 3500:

 

It's the board with the display, IR receiving diodes, the touch switch (Timer and Mute) mounted.

There sits a  chip in the lower left corner which has a printing on it: U2506B

This is the same chip as in the LC2 dimmer. Now read the excellent fault finding description of Frank and do some transfer work. This leads you to the SMD capacitor C18 which is connected to Pin3 on the U2506.

The original one is a 22µF 6,3V so get the same and replace the old one very carefully.

Hope this helps

 

Und das ganze mittels Google Translator:

<------

Hallo,

in Bezug auf den Nicht-IR-Empfang LCS9000 / Beolab 3500:


Es ist die Platine mit Anzeige, IR-Empfangsdioden, dem Berührungsschalter (Timer und Stummschaltung).

In der unteren linken Ecke befindet sich ein Chip mit einem Aufdruck: U2506B

Dies ist derselbe Chip wie beim LC2-Dimmer. Lesen Sie nun die ausgezeichnete Fehlersuchbeschreibung von Frank und führen Sie einige Übertragungsarbeiten durch. Dies führt Sie zum SMD-Kondensator C18, der an Pin3 des U2506 angeschlossen ist.

Das Original ist ein 22µF 6,3V, also holen Sie sich das gleiche und ersetzen Sie das alte sehr sorgfältig.

Hoffe das hilft

<--------

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