B&O Beomaster 1200 Problem

[officialrolfe]

Hi All, I have just acquired a Bang & Olufsen Beomaster 1200 Amplifier.

I plugged in the Beomaster without understanding that the voltage selector was set to 110v instead of the UK's 240v.

There was a slight flash from inside the Beomaster but am unaware of what may have fried. Any help would be greatly appreciated as I would love to get her running again.

Regards,

Ben

[kc8apf]

Looks like a schematic is available on elektrotanya: http://elektrotanya.com/bang_olufsen_beomaster_1200_sch.pdf/download.html. Hopefully the fuses blew quickly and nothing else got damaged.  Start by disconnecting the power supply from all other boards, replacing the fuses, and seeing if the output rails are in spec.

[mzacharias]

Normally the power transformer is the first casualty in this situation.

[Seekonk]

After a certain voltage the transformer looks like a resistor.  It is likely the fuse went before the transformer winding fused. Voltage to other components was likely limited to what they could stand.