Abstract: This invention relates to a trolling motor which includes a control system capable of executing a predetermined sequence of events which will clear entangled weeds from the propeller, motor housing, and support column. The control system for the trolling motor provides momentary reversal of the propeller to accomplish reliable cleaning of the submerged components of the trolling motor without disturbing the operator selected forward speed. The system includes an input for manually activating a cleaning cycle, for periodically activating cleaning cycles, or for automatically activating a cleaning cycle upon detection of weed fouling of the submerged components.

Abstract: A trolling motor system comprises a trolling motor having a propeller rotatably driven thereby. The motor is connected to a rotating tube or column mounted to the boat. A control head is mounted at the upper end of the column. A steering motor in the control head controls rotational position of the trolling motor. The control head houses a control circuit for controlling speed of the trolling motor as well as position of the steering motor to steer the boat. A foot pedal is positioned in the boat in proximity to the control head. The foot pedal includes a plurality of user actuable switches for commanding operation of the steering motor and trolling motor. The commands are transmitted via radio frequency to a receiver in the control head. The receiver decodes the commands and transfers the command to the control circuit.

Abstract: A trolling motor system comprises a trolling motor having a propeller rotatably driven thereby. The motor is connected to a rotating tube or column mounted to the boat. A control head is mounted at the upper end of the column. A steering motor in the control head controls rotational position of the trolling motor. The control head houses a control circuit for controlling speed of the trolling motor as well as position of the steering motor to steer the boat. A foot pedal is positioned in the boat in proximity to the control head. The foot pedal includes a plurality of user actuable switches for commanding operation of the steering motor and trolling motor. The commands are transmitted via radio frequency to a receiver in the control head. The receiver decodes the commands and transfers the command to the control circuit.

Abstract: An ionization smoke and fire detector comprises a molded plastic housing that includes a nodal ring for supporting a vibrating plate that is part of an alarm. The alarm may be driven by piezoelectricity or by an electromechanical device. If the detector is battery powered, a portion of the housing is cut out to permit removal and insertion of a battery holder that makes contact automatically upon insertion to supply electric power to the electronic circuit of the smoke detector. One electrode of a reference chamber for the smoke detector is formed by wave-soldering an open metallized area on the printed-circuit board. Contact with the movable element of the alarm and with a high-impedance input in an integrated circuit are made through springs that are not soldered or welded.

Abstract: A watt/var transducer utilizing the pulse width-pulse height modulation type of multiplying scheme wherein a stable squarewave is generated by switching from one reference voltage to another reference voltage, the output thereof is integrated to produce a stable triangular wave output, the gain of which can be simply adjusted by shorting the output of amplifying means to various points in a resistive means contained in feedback means from the output to the input of said amplifying means. The frequency of the triangular wave output is high relative to any alternating signal which may pass upon the power line to be monitored by the transducer such that those portions of said alternating signal sampled by the multiplier portion of the transducer appear to be non-alternating signals thereby rendering the transducer capable of multiplying alternating signals as well as non-alternating signals.

Abstract: A frequency transducer for monitoring frequency in a power line wherein a frequency representative signal is generated which is twice the frequency of the signal to be monitored in the power line, the frequency representative signal is shaped into a triggering output signal which is supplied as one input to a comparator in a comparator/timer circuit. A second input to the comparator is provided by a timing circuit which produces a reference signal as that second input, said reference signal having a constant non-zero duration, the magnitude of which is dependent upon the timing constant of a resistive-capacitive circuit; said resistive-capacitive circuit being charged by a constant charging current of high value to ensure that variances in the timing constant due to temperature, humidity, contamination and the like are small when considered as a percentage figure.

Abstract: Magnetic cores of clamp-on type current measuring devices having a Hall-effect device for measurement of D.C. currents are provided with stabilizing coils which are periodically energized to substantially eliminate the characteristic hysteresis effect of the core material. A magnetic core of the type which is split to permit opening and subsequent clamping onto a conductor, has one section thereof provided with an air gap in which the Hall-effect device is positioned. A stabilizing coil is positioned on one section of the magnetic core and the coil and is periodically energized with a damped oscillatory current. This damped oscillatory current is at least applied immediately prior to the taking of any current measurement and is preferably applied periodically to maintain the stability of the magnetic core.