A salt level monitoring device for water softeners including a weight for placement upon the salt mass; a drop line connected to the weight at one end and a sensor at the opposing, upper end; and a support member for supporting the sensor and drop line over the salt mass. Once the salt mass drops to a selected level, tension is placed upon the drop line and hence the sensor causing actuation thereof to send forth either an aural or visual signal. The weight has a mass less than the mass of the salt but greater than the mass of brine to prevent the weight from becoming embedded in the salt mass and to prevent false signals. A clip attaches the drop line to the weight for convenient adjustment of the drop line depth so that the salt level may be monitored at selected heights within the softener.

In order to provide an indication of the extent to which creosote has built up in a chimney, an accumulator on which creosote will also build up is held suspended in a chimney in a zone where a major creosote buildup is anticipated. The accumulator is so connected to a normally open switch in a signal circuit that its weight and that of a predetermined creosote deposit thereon will close the switch, a signal is then energized to warn that the chimney should be cleaned or at least inspected.

A portable bin full indicator is disclosed comprising a sensor operable to send a signal when the level of particulate material in a bin reaches the level of the sensor; means to temporarily secure the sensor in a top portion of the bin; an alarm operatively connected to the sensor such that it is activated by the signal; and a battery to supply electrical power to the sensor and alarm. An extensible handle is provided to allow insertion into a bin by an operator standing on the ground, and also an adjustable hook is provided that may be configured for various bins.

A device for monitoring the level of salt in a brine tank. The device includes a housing and a circuit within the housing connectable to an electric power source. An indicator is connectable to the circuit for indicating the existence of a first electrical state and a second electrical state. An actuator member is provided having a first position wherein the indicator member indicates the first electrical state and a second position wherein the indicator member indicates the second electrical condition. A biasing member having a predetermined force biases the actuator member towards the first position. A surface member is provided for resting on the upper surface of the material in the tank, the surface member having a weight greater than the predetermined force of the biasing member and a density greater than water. The surface member is movable in the brine tank as the height of salt therein descends, and is connected to the actuator member, wherein the weight of the surface member causes the actuator member to move to the second position when the surface member descends a predetermined distance.

An electron linear accelerator for use in industrial material processing, comprises an elongated, resonant, electron accelerator structure defining a linear electron flow path and having an electron injection end and an electron exit end, an electron gun at the injection end for producing and delivering one or more streams of electrons to the electron injection end of the structure during pulses of predetermined length and of predetermined repetition rate, the structure being comprised of a plurality of axially coupled resonant microwave cavities operating in the .pi./2 mode and including a graded-.beta. capture section at the injection end of the structure for receiving and accelerating electrons in the one or more streams of electrons, a .beta.=1 section exit section at the end of the structure remote from the capture section for discharging accelerated streams of electrons from the structure and an rf coupling section intermediate the capture section and the exit section for coupling rf energy into the structure, an rf system including an rf source for converting electrical power to rf power and a transmission conduit for delivering rf power to the coupling section of the structure, a scan magnet disposed at the exit end of the structure for receiving the electron beam and scanning the beam over a predetermined product area and a controller for controlling the scanning magnet and synchronously energizing the electron gun and the rf source during the pulses.