Bongkar Rahasia Kualitas Audio dan Restorasi Amplifier Sansui AU-2900

Restoration of a Sansui AU-9200 audio amplifier, manufactured around the 1980s. The damage was characterized by no sound when the audio input was connected to an audio signal source, but the power indicator was lit, and only noise and humming could be heard through the speakers. The power amplifier uses an OCL system with 2SD314 and 2SB508 transistors. These transistors are very rare, so we had to replace them with other types. The power amplifier has a maximum power of 2x30 Watts. Some electrolytic capacitors were replaced; their capacitance had changed due to age.