Beomaster 2400

1st November 2010

This set worked normally when cold but after about half an hour the selected radio station or source would randomly change, all the touch controls could still be operated but the selection could not be held for any length of time. It was also noticed that the fault became worse when the radio aerial was connected. The 15V supply at TP16 was found to be slightly low and containing excessive amounts of ripple, not surprising as the voltage at the emitter of 2TR27 (TIP32A) was only 15.5V. Initially 2C92 (2200uF) was suspected of being open circuit but the actual faulty component was the rectifier 2D50. The current through this part of the circuit can be in excess of 1A so it pays to fit as sturdy a rectifier as can be fitted into the available space. [Beomaster 2400]