Beomaster 901 FM radio. Help needed.

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BO Posted: Mon, Dec 31 2012 3:02 PM

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On my BM 901 the FM radio behaves incorrect. When switching on, when not used for a while, the radio, works correct for about a minute then the signal disappears, only white noise. Switching off and on again, it works for a couple of seconds. All other functions are OK. AM radio works.

Any idéas?

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Dillen replied on Tue, Jan 1 2013 9:45 PM

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Check the power supply voltage and ripple.

Martin

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BO replied on Wed, Jan 2 2013 6:50 PM

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Dillen:

Check the power supply voltage and ripple.

Martin

I found the problem. One of the tantalum capacitors that I've replaced caused the problem. Switched back to the original one and everything works!

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BO replied on Wed, Jan 2 2013 6:56 PM

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Checking with my LCR it shows correct value. I don´t have an ESR meter so I can't really check out properly. This was the second tantalum that caused me problem.

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Dillen replied on Wed, Jan 2 2013 8:30 PM

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Are you sure, you got the polarity correct ?

Martin

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BO replied on Wed, Jan 2 2013 9:01 PM

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Dillen:

Are you sure, you got the polarity correct ?

Martin

No, I'll check that again.

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BO replied on Thu, Jan 3 2013 8:26 PM

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It turned out to be the polarity.

Thanks for the advice.