Sequential Circuits Prophet 5

This instrument had numerous power rail shorts, component failures in the power supply, poorly executed previous repairs, and a very noisy transformer. All parts in the power supply were replaced, including a new toroidal transformer, resistors, capacitors and multi-turn trim pots. The +5v regulator was replaced with a switching device from muRata, and the +5v rail was reworked to eliminate the voltage drop diodes. TVS diodes were added to each power rail for protection, and all tantalum capacitors not in the audio path were replaced.