A signaling device for use in combination with a mailbox. The signaling device comprises a mounting bracket secured to one of the sidewalls of the mailbox and includes a shaft extending outwardly from the mailbox with a portion of the exterior surface of the shaft defining a cylindrical bearing surface. A signal flag comprises an elongated arm having an opening therethrough intermediate the opposite longitudinal ends and adapted to receive the bearing surface of the shaft which thereby pivotally...

A fiber length analyzer is disclosed that detects the various lengths of fibers present in a liquid medium and converts data representing these fiber lengths into a distribution related to the range and relative number of different fiber lengths present in the medium.

A two-way telephone communications system passes signals of one frequency in one direction and transponds with signals of four frequencies in the other direction. The individual signals have a predetermined frequency and have a coded duration. The invention provides a system for recovering, or regenerating, the original signal without introducing frequency shift and without changing the duration of the signal.

A multi-scanner scans a signal according to several different patterns. A scanning pattern selector determines which scanning pattern produced the most efficient coding result, for example, for runlength coding, and outputs a coded signal, coded most efficiently, and a selection signal which identifies the scanning pattern found to be most efficient.

An audiometric signal for testing hearing is disclosed having alternating first and second portions, the first portion having a known frequency and a first amplitude, the second portion having the same known frequency and a second amplitude, the change of amplitude occurring in response to the zero crossing of a duty cycle base signal and coinciding with a zero crossing of the audiometric signal. In one exemplar embodiment, apparatus for generating the audiometric signal is provided, comprising ...

The presence of a signal is sensed by a signal transducer around which an optical fibre is wrapped so that the length of the fibre is modulated by any signal present. A laser supplies coherent light to one end of the fibre and a homodyne detector is provided at the other end. Discontinuities at both ends of the fibre cause multiple reflections which produce differential phase modulations of the signal. The detected signal contains a large number of frequency components and the peak frequency is ...

A control circuit is adapted to control the movement of a pintle relative to the die head of extrusion apparatus. A command signal is supplied to a signal generator, which produces a first output signal in the form of a series of continuous voltage triangles, and a second output signal in the form of unit pulses. An impedance matrix contains a plurality of potentiometers which may be remotely connected to a summing amplifier. The potentiometers are arranged in a numerical order. Odd-numbered pot...

A signal processor is disclosed wherein an intermediate frequency chirp pulse is pulse compressed and the linearly frequency modulated, intermediate frequency component of such compressed pulse is removed. With such an arrangement, various weighting techniques may be effectively used to reduce sidelobes of the compressed pulse while, in a radar system application, retaining the sense of the frequency of a Doppler shifted compressed pulse.

An improved signal isolator including two nonlinear circuits having nonlinear voltage-to-current characteristics, in which an input network is formed by connecting one of the nonlinear circuits in series with the primary winding of a transformer, and an output network is formed by connecting the other nonlinear circuit and an averaging circuit in series with the secondary winding of the transformer. A pulse signal is applied to the input network, the output network or the tertiary winding of the...

A simulator for simulation of signals of a target radiator includes a first free-running frequency generator operating at a first frequency for simulating the intensity fluctuations of a target radiator, an amplitude regulator connected to the free-running generator for controlling the amplitude of the first frequency, a second free-running generator operating at a second frequency lower than the first frequency for simulating the amplitude and phase of a vectoril target representation, and a fr...