Adjustable frequency bridge circuit

Claim 1

A FREQUENCY-SELECTIVE ATTENUATING NETWORK OF THE BRIDGE TYPE COMPRISING A PAIR OF INPUT TERMINALS, A PAIR OF OUTPUT TERMINALS, A SIGNAL SOURCE OF MULTIPLE FREQUENCY CONTENT CONNECTED ACROSS SAID INPUT TERMINALS, A UTILIZATION CIRCUIT CONNECTED ACROSS SAID OUTPUT TERMINALS, A FIRST FIXED RESISTOR CONNECTED BETWEEN ONE OF SAID INPUT TERMINALS AND ONE OF SAID OUTPUT TERMINALS, A SECOND FIXED RESISTOR CONNECTED BETWEEN THE OTHER OF SAID INPUT TERMINALS AND THE ONE OF SAID OUTPUT TERMINALS, A THIRD FIXED RESISTOR AND A FIRST FIXED CAPACITOR CONNECTED IN SERIES BETWEEN SAID ONE INPUT TERMINAL AND THE OTHER OF SAID OUTPUT TERMINALS, A FOURTH FIXED RESISTOR AND A SECOND FIXED CAPACITOR CONNECTED IN SHUNT BETWEEN SAID OTHER OUTPUT TERMINAL AND SAID OTHER INPUT TERMINAL, A FIFTH TERMINAL, A THIRD CAPACITOR CONNECTED BETWEEN SAID FIFTH TERMINAL AND THE JUNCTION FORMED BETWEEN SAID THIRD RESISTOR AND SAID FIRST CAPACITOR, A FIFTH FIXED RESISTOR CONNECTED BETWEEN SAID FIRTH TERMINAL AND SAID OTHER INPUT TERMINAL, AND AN ADJUSTABLE RESISTOR CONNECTED BETWEEN SAID FIRTH TERMINAL AND SAID OTHER OUTPUT TERMINAL.