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This is the second Archived Forum which was active between 1st March 2012 and 23rd February 2022
We have a Beocenter 9500 which is much loved and has worked perfectly up until now (barring the glass issue everyone seems to get).
One day it would simply not turn on & there were no lights visible (no standby light either).
I examined the power cord and found it to be warm - insulation was missing from a small section and there was a partial short which looks to have been many years in the making. Very lucky not to have been shocked! I replaced the power cord and can measure the appropriate voltage where the cord terminates - so power is getting to the beocenter now.
However, there is still no sign of life. There's no standby light, and there's no click of the relay when it is plugged in to the wall. When you unplug it, however, there is a small 'pop' in the speakers.
I have checked the fuses near where the power cord inserts, and all seem to be OK.
Given that there's no click of the relay, I'm thinking that there might be something wrong with the relays themselves. I've had a good search of the web for the issue, but can't find anything addressing this specific issue - most people still seem to be able to hear relay clicks.
Is there something I should check? Is there a common fail mode that is probably happening here?
Any help would be much appreciated. It's a great system and I'd rather have it for many more years.
From the clues you've given --> warm = changes in temperature = dried solder joints.
I'd start by re-soldering the joints at the underside of the main rectifier/power supply PCB underneath and to the rear of the CD - that's the one with the 4 pr 5 (I don't remember exactly) fat capacitors.
Menahem
Probably dumb but did you've checked power supply output? I agree with checking soldiering points, but would definitely start checking power supply itself (no stand by light ;) - good luck with repair
Don't worry - be Happy
Thank you for your reply.
If there were dry joints in the main rectifier/power supply PCB, would we expect the relays still to trigger (and thus click) since they supply the main rectifier? Or is the control of the relays done by the main rectifier/power supply board?
Thanks Bob - no I have not checked the power supply output. What level should I check this? At the transformer taps? Or by the voltage supplied to other modules in the unit?
I'm old fashioned "trouble shooter" hence always start from the cable and follow up through out the appropriate part of diagram , beside you did mentioned blown or replaced fuse. Yes check the voltage on transformer and if that's OK carry on forwards through unit supply points..
All the best
Will give it a go. Fingers crossed it's just a dry joint somewhere. Thanks for the help
Well you guys are the best!
One leg of C17 on the relay/rectifier board was totally dry. Likewise one of the power capacitors was leaking. Touching up the dry solder joint brought the system back to life.
Thank you!
That's what we like - happy ending :) may your BC9500 serve you well years to come ;)
Gratulations! Funny that it proved to be exactly the same problem I had on my BC 9500 (bad joint at C17, please see my thread on the subject). Maybe this should be part of the BC9500 faq.
/Mikael
Beocenter Overture | Beolink passive | CX100 | CX50
alchemy: Well you guys are the best! One leg of C17 on the relay/rectifier board was totally dry. Likewise one of the power capacitors was leaking. Touching up the dry solder joint brought the system back to life. Thank you!
Wow, very good fault finding! Wish I was that smart in electronics!
Brengen & Ophalen
Good Idea Mikael
Mikael: Gratulations! Funny that it proved to be exactly the same problem I had on my BC 9500 (bad joint at C17, please see my thread on the subject). Maybe this should be part of the BC9500 faq. /Mikael
Leslie: Wow, very good fault finding! Wish I was that smart in electronics!
OMG Leslie, really - I was thinking of you as 1 of the Gods - how disappointing
just kidding (I only worship trees, rocks, wind... )
Leslie:Wow, very good fault finding! Wish I was that smart in electronics!
Don't start on it Leslie, a perfectionist like you will go nuts, and then it gets impossible or too expensive
Collecting Vintage B&O is not a hobby, its a lifestyle.
Thanks Mikael - yes looks like it is the same capacitor. I wonder if the rectifier circuit with C17 powers the standby system (and is thus always on even when the unit is in standby - exposed to the most stress). I say this as when my BC9500 wouldn't operate, there was still some voltage on all other boards. Repairing the dry joint on C17 brought the whole lot to life, so I am suspicious that it does supply the standby functions.
Since there were some leaking caps, I intend to replace them, but that'll be another thread!
Finding the dry joint was really luck - once the board was removed it just didn't look right. Thanks again everyone.