This Quad 303 amp suffers from a weak low end and needs a few touch-ups in general. While it has been worked on, the components used were not quite good enough, so a few improvements are needed.
Here we see the results of using good quality caps and slight adjustments to the bias and voltage regulator board.


See a series of 'Restoration Building Blocks' videos on detailed steps in the restoration process:
   • How to safely check the Power Transfo...  


See also playlists on some other completed restoration projects.

PHILIPS BX750A:
   • Philips BX750A tube radio restoration...  

TELEFUNKEN OPUS 2114:
   • Telefunken Opus 2114 stereo tube radi...  

SABA UW-175-Z 3D:
   • Saba UW 175-Z 3D tube radio restorati...  

GRUNDIG 1070:
   • Grundig 1070 tube radio restoration -...  

SCHAUB-LORENZ GOLDY 58 type 3020:
   • Schaub-Lorenz Goldy 58 type 3020 tube...  

BUSH VHF64:
   • Bush VHF64 tube radio restoration - P...  

GRUNDIG 3060A:
   • Grundig 3060a tube radio restoration ...  

TELEFUNKEN OPERETTE 8:
   • Telefunken Operette 8 tube radio rest...  

GRAETZ SUPER 171W:
   • Graetz Super 171W tube radio restorat...  

LOEWE-OPTA MAGNET 3737W:
   • Loewe-Opta Magnet 3737W tube radio re...  

BRAUN ATELIER 3:
   • Braun Atelier 3  

LOEWE-OPTA TRUXA STEREO 4741W:
   • Loewe-Opta Truxa Stereo 4741W  

GRAETZ COMEDIA 616:
   • Graetz Comedia 616 tube radio restora...  

SABA FREIBURG W2:
   • Saba Freiburg W2 (WII) restoration  

GRAETZ MUSICA 4R417:
   • Graetz Musica 4R417 restoration  


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