Frequency measuring system including synchronously variable capacitors and servo indicating means

Claim 1

A READOUT COMPENSATOR FOR USE WITH A FREQUENCY TRACKER OSCILLATOR COMPRISING, SWITCHING MEANS SWITCHING THE FREQUENCY OF SAID OSCILLATOR ALTERNATELY BETWEEN TWO VALUES, FREQUENCY-MEASURING MEANS INCLUDING A CAPACITATIVE SYSTEM ADJUSTABLE TO EITHER ONE OF TWO VALUES OF CAPACITANCE, SAID ADJUSTABLE CAPACITANCE VALUES BEING SELECTED SO THAT AT ANY TIME THE PRODUCT OF THE INSTANT CAPACITANCE VALUE AND OF THE INSTANT OSCILLATOR FREQUENCY IS A CONSTANT, SAID FREQUENCY MEASURING MEANS PRODUCING AN OUTPUT SIGNAL THE AMPLITUDE OF WHICH IS REPRESENTATIVE OF THE PRODUCT OF THE FREQUENCY OF THE SIGNAL IMPOSED THEREON AND THE CAPACITY OF SAID CAPACITATIVE SYSTEM, MEANS APPLYING SAID OSCILLATOR SIGNAL TO SAID FREQUENCY-MEASURING MEANS, AND MEANS OPERATED BY SAID SWITCHING MEANS TO ADJUST SAID ADJUSTABLE CAPACITATIVE SYSTEM ALTERNATELY TO SAID TWO VALUES OF CAPACITANCE AT THE SAME RATE AND IN PHASE OPPOSITE TO THE PHASE OF THE SWITCHING OF THE OSCILLATOR SIGNAL, WHEREBY THE OUTPUT SIGNAL AMPLITUDE OF SAID FREQUENCY-MEASURING MEANS ALWAYS LINEARLY REPRESENTS THE AVERAGE OF SAID TWO VALUES OF OSCILLATOR FREQUENCY.