A high power factor AC to DC power supply having a high frequency pulse producing circuit comprising an inductor supplied with rectified raw AC power through a semiconductor switch which provides dynamic power factor correction by maintaining the width of the on-times of the switch substantially constant throughout each cycle of the input AC power. The peak energy stored in the inductor during the on-times are a function of the amplitude of the instantaneous voltage of said rectified AC power, s...

In a predetection combiner there is provided AGC amplifier which uses an electronically controlled RF attenuator, such as a PIN-diode attenuator, which is linearly controlled by use of digital signals. A programmed read-only-memory provides a linearity correction for generating the appropriate control voltage for the diode attenuation device.

A digitally controlled-operating system comprising a detecting means such as a speed sensor which generates pulses having a frequency corresponding to a detected value, an oscillation circuit consisting of a multivibrator which stops oscillation when the frequency of detected pulses from said detecting means exceeds a predetermined value while it maintains oscillation when the frequency is below the predetermined value, and a logical gate which opens and closes a gate in accordance with the outp...

A construction for a digitally openable container closure which includes at least one inwardly displaceable opening panel each of which is defined by a fracturable web forming a locus of separation of the opening panel from the adjacent portion of the closure, an integral deflectable portion projecting outwardly from the closure adjacent the fracturable web around each opening panel and weakening lines in the closure adjacent each opening panel extending across the closure between the opening pa...

This invention describes a remotely operated digitally variable capacitor. ore particularly, the invention relates to remote rapid tuning of selector circuits in receivers and transmitters and of matching networks. Capacity values are available in discrete multiples of a selected unit, for example, one picofarad. Such capacitor consists of elements which provide capacity changes of 1pf, 2pf, 4pf, 8pf etc.

A digitally controlled oscillator includes an emitter coupled multivibrator with weighted current sources driving the timing capacitor of the multivibrator the weighted current sources being driven by a binary input signal to produce an output frequency corresponding to the binary weight of the input signal. The multivibrator produces output waveforms of either square, triangular or sine waveshapes. The sine wave output is accomplished by the use of anti-parallel diodes in conjunction with the t...

A digitally controllable enhanced field effect capacitor is produced by providing a first source region of a first conductivity type contiguous with a main channel region in a body of semiconductor of a second conductivity type. The source region includes a plurality of source subregions. A plurality of separate regions of the first conductivity type are provided in the body of semiconductor, each contiguous with the main channel region and a separate secondary channel region, each of the second...

At least two attenuator banks are intercoupled in a cascaded arrangement, wherein the signal across each subsequent attenuator bank comprises a differential signal representing a selected attenuation (or voltage) step of the preceding attenuator bank. In this way monotonic attenuator operation is assured.

An intercommunications system for the selective establishment of two-way communications between a multiplicity of stations is disclosed and comprises a terminal located at each station and a communications network including a predetermined number of lines for interconnecting any one of the terminals to at least one other of the terminals. Each terminal comprises an audio subsystem, apparatus for generating digitally coded control words for selecting a particular terminal and for selecting a part...

A digitally-controlled cycloconverter converts a multiple-phase power signal of variable frequency into a single-phase or multiple-phase signal of a lower selected frequency. The cosinusoidal algorithm is utilized to determine the firing delay times, with the analog reference wave used in that algorithm being created from a digitized hardware table. The cosinusoidal algorithm is further simplified by defining the relationship between the analog reference wave and the cosinusoidal timing waves in...