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This is the second Archived Forum which was active between 1st March 2012 and 23rd February 2022

 

Beomaster 2400-2 Repair

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Anil
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Anil Huh? [:^)] Posted: Sat, Mar 18 2017 11:10 PM

I have a Beomaster 2400-2 which is non operational for several years. Only a red LED lights up , None of the touch controls work.

I would like repair it , but have no idea where to start. I don't have the technical Manual as well.

Is it possible to bring it back to life

Thanks

 

Anil

Dillen
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Dillen replied on Mon, Mar 20 2017 6:39 AM

mehtaanil:

Is it possible to bring it back to life

 

Yes.

Martin

Anil
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Anil replied on Thu, Mar 30 2017 2:43 AM

Martin,

Hello, Thanks for assuring me. Please tell me how I should start to bring the Radio back to life

Thanks a lot for your help

Dillen
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Dillen replied on Thu, Mar 30 2017 6:42 AM

We don't know how skilled you are in these matters or which tools and instruments you have at your disposal, but
basically you will have to take a couple of covers off, check things and measure around a bit.

If none of the touch fields are working, you could start by checking if the Beomaster was put together correctly.
If not, there's a good chance the sensor pads little bronze forks aren't gripping their respective pins on the underlying
circuitboard.
All fine but still no go? Check the low voltage power supply for amount of ripple and put an oscilloscope to the
signal from the sensor pad circuits oscillator to see if things are as expected.

In short; Put the patient on the bench with your tools and instruments, study the schematics, - diagnose and repair.

As you work your way around the Beomaster and get things to work, you will most likely find that a more thorough replacement of
capacitors will be in order. some will probably be bad and most will be marginal by now with a loss of capacitance and increased ESR.
Alignment trimmers will also be in need of replacement and realignment.
The idle current settings in particular - so keep an eye on them if you get the Beomaster to power up, a multimeter (or perhaps two) across the
emitter resistors would be fine if your variac doesn't have mains current monitoring.
But get it working first - or at least sort of.

Martin

Craig
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Craig replied on Thu, Mar 30 2017 7:40 AM

Take some pictures too......worth a thousand words

Anil
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Anil replied on Thu, Mar 30 2017 6:46 PM

Martin,

Your ideas are a ray of hope, While I did my soldering & instruments practice in engineering school about 35 years ago. I still feel I could find my way around.

I have a multimeter with me , however no scope, will it be a serious handicap?. You have mentioned changing the capacitors,How do I identify the capacitors rating , is there some readily available list which I can check off.

With the Low Voltage Power Supply, is there any particular voltage to look out? at some TP

And yes I will keep coming back to you if I get stuck somewhere, hope you don't mind.

 

Thanks

Anil
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Anil replied on Thu, Mar 30 2017 6:46 PM

yes Sir

Dillen
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Dillen replied on Thu, Mar 30 2017 6:54 PM

mehtaanil:

How do I identify the capacitors rating , is there some readily available list which I can check off.

With the Low Voltage Power Supply, is there any particular voltage to look out? at some TP

Thanks

The servicemanual springs to mind as the answer to both.
And most caps have their basic specs stamped on them.

Capacitor kits are readily available - but a completely dead Beomaster will most likely not be down to bad capacitors, so I suggest you
do some diagnosing before upgrading/recap'ing.
There's always a risk of introducing new faults that would be difficult to find with the original fault(s) still around.

Martin

Anil
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Anil replied on Thu, Mar 30 2017 7:10 PM

Could I get the manual , so U can refer to it

Anil
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Anil replied on Sat, May 6 2017 8:15 AM

Hi Martin,

After weeks of fiddling around, I have see that the capacitors C58,60,62,64 are showing shorted, What do you advise

Thanks

Saint Beogrowler
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I suggest a full recap with new idle and bias trimmers. Many of those red caps are probably way out spec. Fantastic receiver when it's all done.
Søren Mexico
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Needs a Nickname:
I suggest a full recap with new idle and bias trimmers. Many of those red caps are probably way out spec. Fantastic receiver when it's all done.

Needs a Nickname is right, but as Martin suggest, get the manual, available for silver and gold members onsite, the failing capacitors will not induce a totally dead BM so go looking for more failures (transistors, rectifiers, diodes etc. etc.) before you change caps.

@ Peter: For a nickname I suggest Saint Peter or Beosaint Big Smile

 

Collecting Vintage B&O is not a hobby, its a lifestyle.

Anil
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Anil replied on Mon, May 8 2017 8:02 AM

Many thanks, for your leads, I will sit on it once again over the week end and see if this short is due to some neighbouring Resistor or any other item .

Meanwhile if you think of anything , do let me know.

 

Ottar
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Ottar replied on Wed, Aug 8 2018 6:32 PM

Hello Martin,

I am also refurbishing a Beomaster 2400 (Type 2901), and am looking for a capcitor kit. Do you know where I might locate one?

Ottar

 

Dillen
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Dillen replied on Wed, Aug 8 2018 6:45 PM

Capacitor kit
Lamp kit
Potentiometer repair kit
Other parts...

Email or PM me.

Martin 

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