1.7v on 12v pin in std.by (Beomaster 7000)

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Weebyx Posted: Mon, Sep 4 2017 11:32 AM

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Hi.. I am still struggling a bit with my lightning damaged Beomaster 7000.

It is actually working, there is sound, and display and processor is working. However, I tested it with a set of Beolab Penta speakers, and the "funny" part is that they stay on, also when BM is in std.by.

I tracked it down to 1.7v in std.by on the "speaker on" line, which is 12v supplied by Relay 1, coming from 2 30vac lines via D2. 

40v/-40v, 28v and 12v/-12v is fine when powered on, but 12v stays at 1.7v in std.by. All others go to 0.

As I can see in the diagram, the relay is supposed to turn of all power to this circuit, so where is the 1.7v from ?

There is 5v supplied to the "40/28/12v" part from R56, can these 5v be the culprit ? I cannot see any other way?

Are there anyone with a working Master7000 that could do a measurement of the 12v line on P15-3 when the unit is in std.by ?

Or have any other good ideas on what could be the problem.

Thanks

/Jacob