What's been done......

To my Audio Engineer - Anthony - Many thanks my friend! 

  • Rebuild Power Supply Board
  • Repair Power Suppply Board traces and binding posts
  • Replaced all semi-conductors, capacitors and relays on Power Supply Board
  • Migrate +/- 80V regulators and 13V regulator to Power Amp heatsinks to stabilise power supply and stop any possible damage to the PCB
  • Replacement of constant current sources with new more rugged and stable design on sister board
  • Removal of incorrect value capacitors on Phono pre-amp, replacement of semi-conductors and installation of new capacitors, low leakage and film where applicable
  • Replacement of capacitors on Control Amp, Meter Amp and Tone Amp. Low leakage or film where applicable
  • Repairs carried out to Phono Pre-Amp circuitsand all above PCB's, defluxed, cleaned and protected
  • Left and Right Power Amps rebuilt due to incorrect or sub-standard semi-conductors used in previous repairs. New semi-conductors in all but Ouput Stage and Differential Pair, new capacitors, trimmers and resistors
  • Large Output transistors removed, cleaned and high grade thermal compound applied and refitted
  • Output transistors re-wired
  • Power supply and Soft Start function tested
  • Protection circuit Chip found to be faulty, damaged/fused resistors on the 80V regulators
  • Replacement Genuine Pioneer PA3001 Chip fitted and new resistors fitted and tested
  • Tuner board capacitors replaced and upgraded to film where applicable. Some semi-conductors replaced
  • APC checked and capacitors upgraded to stable film type capacitors
  • Main power capacitors and bridge rectifiers for Power Amps fully rewired and attached to new 47,000uF Capacitors
  • Power Supply Board, Phono Pre Amp fully re-wired and wire wrap technique used on binding posts
  • Wiring looms made for +/- 80V and 13V regulators and relocation to main heatsinks.
  • Soft Start circuit tested with new larger capacitors - Passed
  • Power Amps checked, idle current set and DC offset calibrated. Rechecked for reliable behaviour
  • Level Meters calibrated
  • Tuner, APC and FM font end adjusted and full FM re-alignment carried out to bring back signal strength, minimal distortion (THD reduced to 0.016% @ 60db 1kHz) and Quartz Lock. Touch Control found to be faulty
  • Touch sensor circuit rebuilt using correct transistors and calibrated
  • Mains Input fuse holder replaced with new
  • System soak tested and run to ensure reliability and burn in new components and ensure thermal stability
  • New wooden case made, stained and glossed
  • Front fascia deep cleaned including all knobs and switches
  • All switches cleaned with high quality contact cleaner
  • Left Power Amp mounting screws found to be stripped. Heatsink tapped and new screws fitted to both rear mounting points and top side mounting point