Abstract: A digitally-controlled SAW stabilized FSK oscillator circuit having an oscillator and a single-port SAW resonator with a predetermined circuit resonant frequency and being coupled to the oscillator for establishing a first oscillator output frequency, F.sub.SAW. A bipolar transistor has at least one predetermined shunt capacitance value, C, that is placed in electrical series with the single-port SAW resonator when the transistor is in the OFF state and a closed switch that replaces the capacitance when the transistor is in the ON state to cause the first frequency, F.sub.SAW, to be generated by the oscillator when the transistor is ON and to cause a second frequency, F.sub.2, to be generated by the oscillator when the transistor is in the OFF state.

Abstract: A low-power, self-quenching superregenerative receiver utilizes a single-port SAW device coupled to an RF oscillator to establish the frequency of oscillation at the output of the RF oscillator. A diode detector is coupled from the oscillator output for detecting a predetermined amplitude of the oscillation output signal. A time-constant circuit is coupled from the signal detector for generating an oscillator quench signal when the oscillator signal is detected and the oscillator quench signal has a predetermined duration set by the time-constant circuit. A feedback circuit couples the oscillator quench signal to the RF oscillator to cause the RF oscillator to switch to a non-oscillating condition only during the predetermined duration of the RF oscillator quench signal. The RF oscillator then switches to the oscillating condition and the system repeats itself.

Abstract: Disclosed is an electronic sensor and control for monitoring the rate of transport of grain elevator buckets, the electronic control including a metal detector probe for sensing the passage of the buckets past the head and a control module for processing the signals from the head to produce a D-C voltage proportional to the bucket transport rate. Trigger networks responsive to the D-C voltage activate appropriate alarms and shut-down of various phases of the grain elevator operations. An automatic calibration control enables calibration of the D-C voltage for different desired rated speeds of the bucket transport.