Percussion circuit for electronic organs

Claim 1

A BIASING AND CONTROL CIRCUIT FOR ELECTRON TUBES IN A PLURALITY OF PERCUSSIVE AMPLIFIERS WHICH IS ADAPTED NORMALLY TO MAINTAIN EACH ONE OF SAID PLURALITY OF AMPLIFIERS IN A CUTOFF CONDITION AND TO ALLOW A SINGLE SELECTED ONE OF SAID PLURALITY OF PERCUSSIVE AMPLIFIERS TO PASS AN ELECTRIC SIGNAL SIMULATING THE FAST ATTACK AND SLOW DECAY OF A NOTE PRODUCED BY A MUSICAL INSTRUMENT COMPRISING, A SOURCE OF BIASING VOLTAGE HAVING A FIRST AND A SECOND TERMINAL, A PLURALITY OF FIRST AND SECOND RESISTORS, A POTENTIOMETER CONNECTED AT ONE END TO SAID FIRST TERMINAL, MEANS SERIALLY AND SEPARATELY CONNECTING SAID PLURALITY AND FIRST AND SAID SECOND RESISTORS BETWEEN A POINT ON SAID POTENTIOMETER AND A FIRST ELECTRODE OF EACH ONE OF SAID ELECTRON TUBES, MEANS CONNECTING A SECOND ELECTRODE OF EACH ONE OF SAID ELECTRON TUBES TO SAID SECOND TERMINAL, A SIMILAR PLURALITY OF SINGLE POLE-DOUBLE THROW SWITCHES, MEANS SERIALLY CONNECTING SAID SIMILAR PLURALITY OF SINGLE POLE-DOUBLE THROW SWITCHES BETWEEN SAID SECOND TERMINAL AND THE OTHER END OF SAID POTENTIOMETER WHEREBY WHEN EACH ONE OF SAID SIMILAR PLURALITY OF SWITCHES ARE IN SIMILAR POSITIONS A FIRST LOWER BIASING VOLTAGE FROM SAID SOURCE OF BIASING VOLTAGE IS IMPRESSED ON CORRESPONDING ELECTRODES OF SAID ELECTRON TUBES TO MAINTAIN EACH OF SAID ELECTRON TUBES IN A CUTOFF CONDITION, A SIMILAR PLURALITY OF SIMILAR CAPACITORS, MEANS CONNECTING A DIFFERENT ONE OF SAID SIMILAR PLURALITY OF SIMILAR CAPACITORS BETWEEN THE JUNCTION OF A DIFFERENT ONE OF SAID PLURALITY OF FIRST AND SECOND RESISTORS AND SAID SECOND TERMINAL, AND MEANS SEPARATELY CONNECTING EACH ONE OF THE JUNCTIONS TO A SINGLE SECOND CONTACT IN SAID SINGLE POLE-DOUBLE THROW SWITCHES WHEREBY THE BIASING VOLTAGE ON A SINGLE SELECTED ONE OF SAID ELECTRON TUBES MAY BE CHANGED BY OPERATION OF A SELECTED ONE OF SAID SINGLE POLE-DOUBLE THROW SWITCHES TO PLACE SAID SINGLE SELECTED ONE OF SAID ELECTRON TUBES IN A CONDUCTIVE STATE AND RETURN OF SAID SINGLE POLE-DOUBLE THROW SWITCH TO ITS ORIGINAL POSITION CAUSES SAID SELECTED ONE OF SAID ELECTRON TUBES TO RETURN TO ITS NON-CONDUCTIVE STATE IN ACCORDANCE WITH THE RATE OF CHARGING OF ITS ASSOCIATED CAPACITOR TOWARD SAID FIRST LOWER BIASING VOLTAGE.