Pioneer A-307R Amplifier Repair

Fault Intermittent loss of Audio at low volume. The A-307R produces an impressive sound clarity and range. The design incorporates a mixture of surface mount and discrete components. As can be seen from the video the main circuit board was covered in a heavy layer of dust, a stiff brush and compressed air was used to clean the internals of the Amplifier thoroughly. Straight forward repair, due to the age of the Amplifier and usage the speaker protection relay contacts had become resistive and oxidised. All the three relays in the Amplifier replaced fixing the issue. As is always the case with any Amplifier repair all circuit boards were checked for suspect bad solder joints, the A-307R is well designed so non were found. User controls cleaned with De-Oxit to ensure noise noise free smooth operation. Bias for each channel checked no adjustment required. Amplifier fully tested working correctly.