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Old 27th November 2010, 05:45 PM   #1
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Default Aleph 3: rail voltage as dc offset

One of the channels of my Aleph 3 suddenly has the entire + rail voltage as dc offset. Its a standard build per the schematic in the service manual and it has worked fine for almost a year. There was a popping sound in one speaker and the cones were in a sucked out state. (A frightening sight!).
The speaker survived, but now as I roll up my sleeve to take it apart and troubleshoot, I was wondering if someone here could point me to some obvious places to look for issues. I searched here a bit but couldn't find anything similar(rail voltage on the output) discussed.

Thanks for any pointers.
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Old 27th November 2010, 05:57 PM   #2
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either lower side is not conducting , or upper side went south

there is no easier way than - after visual inspection for loose wires and parts , to check part by part

believe me - after few decades in repair biz - that's usually fastest approach , at least when dealing first time with some gadget
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Old 28th November 2010, 03:04 PM   #3
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I can see this is going to be a tricky one. As I was poking through checking the voltages, just as suddenly the offset switched back to a normal 11-12 mv. I guess I'll resolder all the points for a start.
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