Beogram 4000

2nd July 2013

This machine would switch on with the platter rotating and light displays working normally but the arm would not move because the servo motor was not turning. There was no voltage across the motor but each terminal was a +24V, so something was clearly amiss in the tracking circuit. Both 1TR29 and 1TR30 (BC143) had shorted junctions, presumably the failure of one had overloaded the other – replacement cleared the fault with no other components damaged. A BC161 can be used to replace the BC143 if the latter is unavailable. [Beogram 4000]