Beomaster 6000 4channel

16th June 2013

When switching this receiver on the display for the sound functions illuminated but no sources could be selected and the outputs were silent. The only control which functioned was the standby key, which worked correctly. The +18V supply was found to be low at +0.8V and the -5V supply high at -22V, with 5TR2 (BC119) overheating. This suggested that there was a short circuit across the +18V supply somewhere, with a resistance of only 35 ohms being measured accross the collector and emitter of 5TR2. Disconnecting the +18V feeds to the various PCBs narrowed the area of interest down to PCB8, where 8C24 (4.7uF) was found to be short circuit. A replacement restored normal operation, surprisingly the power supply regulator circuit had not been damaged by this fault. [Beomaster 6000 4channel]