Abstract: A double-double-balanced mixer includes first and second radio frequency baluns and first and second local oscillator baluns formed on a dielectric substrate and connected to two diode rings. An intermediate frequency port is also connected to two diode rings. The particular dimensions of the stripline mixer are carefully selected to provide high dynamic range, strong suppression of intermodulation products, low conversion loss, and low local oscillator input power. The specific design dimensions of the mixer are selected contrary to conventional mixer design principle. For example, the local oscillator and radio frequency balun microstrips are designed to have a length which is considerably less than one-quarter wavelength of the LO and RF frequencies.

Abstract: A compensation circuit including resistors, capacitors and a varactor diode powered simultaneously by the same voltage source applied to a voltage controlled oscillator for reducing deviation from a desired oscillator output frequency on power-up. When power is applied, an exponentially varying voltage is applied to the varactor diode changing its capacitance in such a manner as to change the oscillator frequency in the opposite direction to its natural drift tendency, thus producing a substantially constant output frequency over the period of interest.

Abstract: A noise blanker is disclosed which blanks out impulse noise emanating from the alternator, ignition systems of motor vehicles, and other sources. This is accomplished by delaying an input IF signal while generating a blanking gate pulse occurring at the same time as the noise pulses. These blanking pulses are then used to turn off the delayed IF signal precisely where the noise occurs, resulting in noise-free audio reception. The noise blanker operates to detect noise pulses by detecting the leading edge of any narrow pulse which is received at the front end of the receiver and is reflected in the IF input signal. At the same time, by virtue of the operation of an AGC amplifier the noise blanker's vulnerability to interference or capture by continuous-wave signals is reduced.

Abstract: A noise blanker is disclosed which blanks out impulse noise emanating from the alternator, ignition systems of rotor vehicles, and other sources. This is accomplished by delaying an input IF signal while generating a blanking gate pulse occurring at the same time as the noise pulses. These blanking pulses are then used in turn off the delayed IF signal precisely where the noise occurs, resulting in noise-free audio reception. The noise blanker operates to detect noise pulses by detecting the leading edge of any narrow pulse which is received at the front end of the receiver and is reflected in the IF input signal. At the same time, by virtue of the operation of an AGC amplifier the noise blanker's vulnerability to interference or capture by continuous-wave signals is reduced.