Abstract: A lightweight detachable air coupler for an air seeder comprises an aluminum frame having two steel sleeves die cast into the frame. The frame is provided with two circular apertures each being defined by a rim having an internal cylindrical surface. The steel cylindrical sleeve has a first end having an exterior surface that is diagonally knurled. Two steel sleeves are mounted in the mold for the aluminum frame and cast aluminum is injected into the mold. The liquid aluminum adheres to the knurled exterior surface of the steel sleeves. The aluminum frame has a front surface from which the rims project and a rear surface from which the sleeves project.

Abstract: A self-regenerating filter unit having a housing which carries an ultrasonic transducer periodically energizable to dislodge caked solids from a filter element in the housing. The removed solids collect in a storage zone where they are periodically removed.

Abstract: The present invention is an apparatus and method thereof for performing frequency hopping communication with another party over a subset of hopping frequencies from available frequencies. The spectrum is arranged into a plurality of segments, with each segment corresponding to a subset of the spectrum of frequencies, preferably a contiguous subset of the spectrum. The apparatus includes a communication device for communicating with another party. The communication device receives data over a used segment from a plurality of the segments and signal strength data indicating a current reception power level for the hopping frequency from the other party. A processing unit analyzes the received data to determine an occurrence or non-occurrence of an error over the used segment and notifies the other party to modify the current transmission power level for that used segment according to the occurrence or non-occurrence of an error, via said communication means.

Abstract: A temperature compensated photovoltaic module (20) comprised of a series of solar cells (22) having a thermally activated switch (24) connected in parallel with several of the cells (22). The photovoltaic module (20) is adapted to charge conventional batteries having a temperature coefficient (TC) differing from the temperature coefficient (TC) of the module (20). The calibration temperatures of the switches (24) are chosen whereby the colder the ambient temperature for the module (20), the more switches that are on and form a closed circuit to short the associated solar cells (22). By shorting some of the solar cells (22) as the ambient temperature decreases, the battery being charged by the module (20) is not excessively overcharged at lower temperatures. PV module (20) is an integrated solution that is reliable and inexpensive.

Abstract: An electronic data transmission system has a low peak-to-average power ratio by including a transmitter circuit which receives an input signal and in response generates a distorted output signal. This distorted output signal is generated such the output signal has a large magnitude when the input signal has a high probability of occurrence, and the output signal has a small magnitude when the input signal has a low probability of occurrence. The distorted output signal travels over a communication channel to a receiver circuit which regenerates the input signal by amplifying the distorted output signal with a gain that is the inverse of the gain by which the distorted signal is generated.