This invention relates generally to signal processing techniques for removing or reducing the effects of instabilities in pulsed signal sources, as in phase echo systems using a pulsed signal transmitter source, and, more particularly, to a technique for compensating for the varying amplitude, frequency and/or phase characteristics of the signal source pulses during operation.

A method and apparatus for compensating for a distortion component of a device such as a power amplifier can be achieved without requiring a demodulator. A voltage controlling a gain of the amplitude of the input signal based on the amplitude control signal generated in the amplitude control signal generation step.

An intermodulation distortion analyzer generates two pairs of sinusoidal test tones to serve as a test signal for the channel under test. The two pairs of tones simulate two respective noise band test signals but eliminate the long time averaging required for measurements when noise bands are used. A highly linear AGC circuit employs sampling at an output-controlled duty cycle to maintain a constant reference level for the analyzer. This reference level permits automatic distortion measurements ...

An organ of the type which includes a disc with optical tracks and a row of photovoltaic cells that generate an output dependent upon the light shining through the tracks, which reproduces the sounds recorded on the tracks with a minimum of distortion. An amplifier for coupling to each photocell has an input impedance that is at least an order of magnitude less than of the cell, so that the amplifer substantially short circuits the cell to cause operation of the cell in a current mode, the ampli...

A method of measuring frequency delay distortion of a communication channel comprising, generating at a sending end of said channel a plurality of sustained sine wave signals distributed throughout a frequency spectrum of said channel, modulating at a lower frequency each of said sine wave signals in repetitive progression for a preselected period of each, transmitting the modulated signals over said channel to its distant end, and at said distant end, locally generating a signal of frequency su...

A saturable reactor in series with a horizontal deflection coil introduces a parabolic reactance variation which corrects for side pincushion distortion in a television cathode ray tube. A bridge rectifier circuit rectifies a sawtooth output from a vertical deflection circuit to produce a triangular waveform which is applied to one control winding of the saturable reactor. A remaining control winding is coupled to a DC bias source.

Disclosed are a method and apparatus for detecting distortion in glass, particularly glass ribbons, by scanning the glass with a light beam and photoelectrically measuring the rate of change of the widthwise, center-to-center spacing betweeen a reflected image of said beam from one surface of the glass and a reflected image of said beam from the opposite surface of the glass. The center-to-center spacing of the reflected beams varies as the distortion in the glass varies, and the rate of change ...

In a casing of a device provided for compensating pincushion distortion in television receivers are arranged holes in which are placed compensating magnets. These magnets cooperate with a core and coils located within the casing.

Nonlinear distortion in the transmission signal of a signal path is selectively compensated by the introduction of a distortion cancelling signal. A compensation circuit utilizes a portion of the transmission signal to generate the signal used in cancelling the distortion. In one embodiment of the compensation circuit, a squarer and a multiplier serve to produce a third order distortion cancelling signal. This distortion cancelling signal is then coupled to the signal path with its phase and amp...

A method of and apparatus for determining surface distortion, e.g. surface flatness, of a piece of glass as a function of position on the glass surface are disclosed. The piece of glass is displaced at a constant speed along a predetermined path relative to a light source, e.g. a continuous laser, and a position sensing photo detector. The laser and detector are in spaced relationship to each other and to a first surface of the piece of glass such that a laser beam directed to the first surface ...