ARCHIVED FORUM -- March 2012 to February 2022READ ONLY FORUM
This is the second Archived Forum which was active between 1st March 2012 and 23rd February 2022
Hi
Could someone tell me on the beosound 3 where is located the positive and the negative on the plug of the charger ???
Fairly common. Negative outside. Positive innerside. Diagram shows protection also in case of wrong connection.
Thank you beobuddy.
I charged it but nothing turns on. So had to completly dismantle it.
Here is the picture of the pcb and the arrow were the power comes in, it's on the top PCB (I do not have the service manual for this one), but the power does not come out anymore of the SMD, as they are surface mount no inscription on it and I suppose at B&O it is in a pcb replacement basis.
Does anyone knows the value of that SMD ???
Still looking for the value of the SMD
Happy Holidays to all beoworld members
I think your looking at a capacitor, so it's obvious you don't measure any voltage there.
chti59: I charged it but nothing turns on. So had to completly dismantle it.
Did you check the battery first?
You should get the service manual for the Beosound 3. I guess there's everything you need to know inside.
You can measure voltages accros capacitors.
More interesting is the diode next to it. If it's shortened then there probably a problem and the culpritt. Don't have the diagrams available.
The diode can prevent wrong connected powersupply in 2 different ways. In series with the positive lead, or parallel on the positive and negative lead.
Thank you for all replies.
Yes of course I checked the battery, as I start from the battery testing the voltage at the bottom of the unit and going up until there is no more voltage (since the unit does not power on), then it must be somewhere there.
But it is getting smaller and I am getting older ;) so not easy
@Beobuddy
Well the power (+/- 12 volts if I remember) enters from the bottom card through a flat wire, it is not the one you see on the picture, then it enters that smd directly, but does not come out anymore. So I have deducted that it should be that SMD.
I have checked over the internet resistances have the value on it, but not the capacitors, and since the power does not go thru I will not be able to unsolder it and mesure the value.
I have no idea if such details are still on the service manual as I tried to fix a beosound 1 and there is no such details on the service manual, just tests and card exchanges.
chti59: Well the power (+/- 12 volts if I remember) enters from the bottom card through a flat wire, it is not the one you see on the picture, then it enters that smd directly, but does not come out anymore. So I have deducted that it should be that SMD.
If this a multilayer pcb, which it probably is, you can't be sure that the power enters that smd directly. And suppose it does, what if there is a short behind that smd?
Looking at all the via's (holes through board), it is a multilayer pcb. At least 2 layers.
Without a servicemanual you can't measure properly, only a bit quessing.
Well I do not know if this is a usual thing to do, but to be shure I always put my multimeter in the bip position (continuity) and test from the card where I have found the voltage and goes up until I hear bip, means that I am shure it goes from one point to the other.
Then as said up somewhere, if there is a short above the SMD, it's another problem.
But you have to start from somewhere.
My concern is :
Does the service manual has details or it is just like the beosound 1 where you have a block diagram and a wiring diagram but nothing else that could help you to track a problem on the card itself.
Then a service manual is useless, as it is only on a card exchange basis.
And ecologicaly speaking I hate that. Changing a complete card for a simple cheap component.
But that's how the world is working today and I can try as hard as I can I was not able to change it :o(
Happy new year to all of you.
Just only wiring diagrams. Very little details. Only connectors with some info. But no circuit board details.
So, with multilayer PCB's (some up to 16 layers!) it's very difficult, probably not possible to say, to find the culpritt.
The trace leaving the lower end of the component you have marked with the arrow seems way too thin to be carrying the power for the entire circuit board, so I don't think you are looking at a potential problem spot; besides, the component seems like a ceramic capacitor to me and obviously should not conduct.
The traces on the other side of the board show through so this seems like a quite ordinary two-sided through-plated PCB to me, and there's little reason why it should be more complicated (and more expensive) than that. The upper end of the SMD component goes immediately to a heavy trace and through a via to the other side. The lower end goes to one of the lined up vias on the edge of the PCB, and apparently also to another trace that is covered by the arrow so I have no idea where that leads. All in all, I see little evidence that this would be the spot where the power for the Beosound is interrupted.
--mika