Disclosed is a method and apparatus for adjusting the gain in a weather radar receiver to correct for precipitation induced transmission path attenuation. The receiver gain is controlled in a known manner to accommodate known path transmission effects. The gain controlling apparatus comprises fixed and variable AC resistances, where the variable AC resistance is an attenuator diode driven by a varying current source. The variable current source provides an approximation to a hyperbolically decre...

A transistorized active switch radar pulse modulator has a unique means for pulse current control which includes a transformer interconnected with a magnetron. Transistor switches and related circuitry pulse a step up transformer with voltage pulses to drive the magnetron with a desired current pulse having the appropriate shape and width. A capacitor in the secondary of the transformer acts as a load to the transformer prior to the conduction level of the magnetron so that no current transients...

An automatic data input/output system has combined card reading and recording device features which permit a pilot to totally utilize same as part of an aircraft navigation system. A small light weight drive system is incorporated within the device to move the magnetic card with respect to the read-write heads. The operational modes of the system include a MONITOR MODE, a RECORD MODE, an ENTER MODE, and an ERROR MODE. This permits a pilot to encode or record navigational data on a magnetic card ...

A tool for handling integrated circuits to facilitate their installation on and extraction from circuit boards. A pair of spaced apart levers are pivotal about integral hinges in a manner to engage opposite ends of the integrated circuit. Each lever carries a pair of lugs between which the ends of the integrated circuit are gripped. The opposite end of the tool is constructed similarly although with a pair of levers that are closer together in order to handle a smaller integrated circuit.

The disclosed deviation driver circuit is capable of producing a difference voltage having a magnitude related to the voltage of a deviation signal provided to the circuit from an external source. The deviation driver circuit of the present invention is comprised of a differential amplifier with negative feedback. This differential amplifier includes a pair of transistors and a plurality of load resistors which are arranged to form a balanced bridged network. Since one input of the differential ...

A single crystal controlled oscillator provides clock pulses that are used to drive both the decoder shift register and the encoder shift register of an ATC transponder. An input pulse of the interrogation signal from a ground station is shifted down in the decoder shift register and is time correlated with a subsequent pulse of the input signal to verify the validity of the interrogation. A valid interrogation signal triggers gate logic circuitry which loads data into the encoder shift register...

A pressure transducer includes an electromagnetic drive coil which vibrates a thin walled cylinder at a natural vibrational mode. A capacitor unit senses the vibrational frequency of the cylinder and gives an output signal corresponding to the pressure differential between a fluid contained within the cylinder and a vacuum reference that is maintained adjacent to the exterior surface of the cylinder. Electric heaters maintain a constant operating temperature of the transducer.

A switch structure detects acceleration in a preselected direction such as, for example, along the pitch axis of an aircraft. The switch has a spring supported mass urged toward a stable centered position within the switch housing. Acceleration displaces the mass such that it trips a spring wire switch mechanism for controlling such avionic devices as the autopilot system of the aircraft. A pair of solenoid coils are wound around the spring mass system on opposite sides of the centered position ...

A command bar gives pitch and roll commands to an aircraft pilot. The command bar is carried on a magnet assembly which is supported to pivot on a pair of perpendicular edges that correspond to the pitch and roll axes. A permanent bar magnet included in the assembly has its opposite ends received within bobbins on which coils are wound. The coils are arranged in a plurality of separate tiers located above and below the ends of the magnet. Fields are generated by the coils to selectively deflect ...

This invention relates in general to a universal frequency synthesizer which is suitable for use in a phase-locked loop frequency synthesizer system comprising a voltage controlled oscillator, a reference oscillator and a low pass filter. The universal frequency synthesizer of the present invention is basically comprised of programmable divider circuitry and a phase detector. The universal frequency synthesizer is arranged to receive tuning data in serial format from an external source. The rece...