Abstract: Switching equipment for numerically controlled machine tools is provided with at least one controllable switch for initiating a measuring process and a switch control which closes the switch when a supply voltage appears on a connecting wire, for example on a power supply connecting wire of an electric pump for cooling water. Therefore it is possible to measure automatically without any additional program-steps of the central processing unit.

Abstract: An electronic apparatus adapted to be used with a detachable member, such as a memory pack. The apparatus includes a pair of terminals arranged in the electronic apparatus for detecting an incorrect connection of the electronic apparatus with the memory pack. Also provided is a transistor connected to the terminals for disabling a power supply of the electronic apparatus in response to the terminals detecting an incorrect connection between the memory pack and the electronic apparatus.

Abstract: A portable, modular small appliance control system for lamps and the like, which allows separate control of each outlet of a multiple outlet receptacle from separate and remote locations.

Abstract: A low voltage switch without moving elements, uses a triac power switching element in series with the AC load. A flip-flop circuit provides latching operation for On and Off functions. The triac is isolated from low-voltage actuating circuitry by an optoisolator which draws power from a step down transformer. The transformer also isolates the AC line from the manual switch circuits. A metal case is heat sink for the triac switching element. A threaded nipple, an integral portion of the casing, can be inserted through plug openings in standard electrical junction boxes to form a continuous heat flow path from the triac into the juncture box.

Abstract: The present invention relates to a display device for a digital trip device associated with a current breaking device. The trip device comprises apparatus for entering operating parameters and apparatus for measuring the current in the breaking device, these two apparatuses being coupled with a first microprocessor comprising memory areas in which the parameters and measurement data are entered. The display device is of the portable type, able to be coupled temporarily with the trip device, and comprises: an alphanumerical display, a second microprocessor comprising memory areas, apparatus associable with complementary apparatus in the trip device to transfer the contents of the memory areas of the trip device to the memory areas of the display device, these contents then being able to be displayed selectively by the reader during or after the temporary coupling.

Abstract: A preheating timer for use in an oven unit ensuring uniform finish of cooked (or baked) food independent of high and low initial temperatures in the oven chamber, by applying a simplified electric circuit wherein it automatically determines the preheating time in response to the initial temperature in the oven chamber comprising; a capacitor simulating a temperature characteristics; the first resistor for charging the capacitor from the DC voltage circuit through a reverse-current inhibit diode; a voltage detection circuit composed of zener diode(s) and a transistor for detecting a voltage in the capacitor terminal; and the second resistor for discharging capacitor from the output terminal of the reverse-current inhibit diode.

Abstract: A variable speed trigger switch particularly adapted for use with electric power tools such as drills. The trigger switch features clam shell construction and a single vertically disposed circuit board thereby facilitating assembly and resulting in a low cost and compact unit. Wire connections are kept to a minimum through use of the circuit board in accordance with this invention having power contact resistance and wire terminal connectors formed directly on the board. The trigger switch includes a locking feature enabling the trigger switch to be locked at a desired position and further provides an adjustable detent which can be felt by the user during trigger retraction. The electronics package of the trigger switch employs an electronic motor speed control circuit which provides a combination of open loop and closed loop motor control.

Abstract: A drive control system for driving an electrically driven window or sun roof is disclosed. A control unit drives a vehicle mounted device until it reaches a limit position when an ignition key is not inserted and when a door of the vehicle closes. Accordingly, a usual operation by a driver of the vehicle which occurs when he stops and gets out of the vehicle involves stopping the engine, withdrawing the ignition key, opening the door to get out of the vehicle, and closing the door. When it is desired to leave the window or sun roof in a half-open condition in order to prevent the parked car from overheating, the control unit stores any drive of a vehicle mounted device in response to an input when the ignition key is not inserted into the receptacle of the ignition switch, and controllably drives the vehicle mounted device until it reaches a limit position in response to a combination of the absence of the ignition key inserted into the receptacle, a closing of the door and the absence of stored information.

Abstract: A circuit for supplying current to a load connected to a pair of output leaves of the circuit has at least one feed circuit, an electronic switch disposed between the feed circuit and the leaves having a transistor with a control electrode and a controlled path, and a control means for operating the electronic switch to disconnect the feed circuit from at least one of the leads when the feed circuit de-energized and to connect the feed circuit to at least one of the leads when the feed circuit is energized. The control means has a further transistor with a controlled path connected in series with the control electrode of the transistor in the electronic switch, and a control electrode connected to the controlled path of the transistor in the electronic switch. The control means further has a resistor connected between the control electrode of the further transistor and one of the load leads.

Abstract: A power adapter for timed control of auxiliary electrical loads is provided for connection between a streetlight fixture or the like and a control module of the fixture. The adapter has a weather-resistant housing and an electrical jumper in the housing extending a power source connection to an input of the module, another jumper returning a control output from the module to a main load of the fixture. An auxiliary socket at the side of the housing powers the auxiliary load, which can be a holiday lighting display. In one version, the adapter has a clock timer for controlling the auxiliary load independently of the main load. In another version, a programmable delay timer, synchronized with commencement of main load operation, terminates operation of the auxiliary load following a predetermined interval of main load operation.

Abstract: A cable assembly is described, for safely connecting an electrical power source such as an electrical outlet at an airport, to a power consuming device such as an aircraft. The assembly includes an electrical cable (18) with a connector (16) at one end for engaging the receptacle on an aircraft to supply power thereto, and a relay (30) at the inner end of the cable which can connect and disconnect a power source to the cable. "On" and "off" power switches (32, 34) are located near the outer end of the cable. The "on" switch enables a workman to operate the remote relay to turn on the power immediately after he has connected the outer end of the cable to the power consuming device. This encourages the workman to apply a voltage to the cable only after the connection is made, to avoid sparks that might ignite flammable fumes.

Abstract: The invention relates to a relay authorizing or interrupting the flow of a current in a load circuit.This relay comprises a static electronic switch connected to the load circuit, a control circuit connected to the switch for authorizing or interrupting the flow of current in the load circuit due to the switch. The control circuit comprises a supply input connected to one point of the load circuit and, connected in series between said input and the load circuit, a control switch, a current generator with two terminals and at least one impedance limiting the current flowing in the load circuit to a negligible value compared with the value of the current flowing in the load circuit when said flow is permitted. The voltage at the terminals of the generator is at least equal to the highest voltage between two random points of the load circuit.Application to circuits in which flows a current with a random direction or an alternating current, or to a current inverter.

Abstract: A drive for a high-voltage isolating switch includes a shaft which acts on a moving contact of the isolating switch, a flywheel which is connected via a coupling to the shaft, a drive motor for energizing the flywheel before a switching process begins and a control circuit. The control circuit is used for determining the direction of rotation of the drive motor during the energizing process and for automatically switching the drive motor from a motor to a generator operation, during a period when the movable contact is to be moved. The motor is preferably a series-wound motor which provides high operational reliability. A rectifier is connected in the current path between the rotor and stator windings of the motor. The rectifier stabilizes the current direction in the stator winding during the switching-over phase of the drive motor from motor to generator operation.

Abstract: An electrical circuit is disclosed which provides the capability of starting up an unattended computer or similar device either from a remote location or at a predetermined date and time. The circuit includes an electrical energy storage device which, when a telephone ring signal is detected, initiates start-up of the computer. Alternatively, an interrupt from a date timer may initiate start-up of the computer using the energy storage device. Once start-up of the computer is initiated, its power supply provides the necessary voltage which, in conjunction with a latching transistor, maintains the electrical circuit providing AC power to the power supply and computer and recharges the electrical energy storage device. Finally, an electrical signal to power-down the computer may be initiated either remotely or through software instruction.

Abstract: A system for automatically controlling lighting fixtures, appliances, an alarm, or the like in a room or enclosure has a pair of sensors installed in association with each entryway leading into a room. The sensors are triggered when a person passes through the entryway and send a signal to a logic circuit which is mounted in operative association with the sensors. The logic circuit distinguishes between entry or exit of persons from the room on the basis that in each entryway or door one of the two sensors is triggered first in case of entry, and the other one of the two sensors is triggered first in case of exit. The signals signalling entry are counted and stored in a first counting register separately from the signals signalling exit of persons from the room which are counted in a second counting register. The status of the first counting register storing the number of entries is continuously compared in a comparator circuit to the status of the second counting register storing the number of exits.

Abstract: The present invention provides a power supply for a digital light controller which is placed in a wall box where the neutral line cannot be used. The invention uses two separate and different kinds of power supplies that are placed in series with the load and the digital light controller depends on the power supply 1 when the load is off and on the second power supply when the load is on. The supplies are alternately switched when either the remote control or a manual switch is triggered. The first power supply uses a switch that is either opened or closed to develope a voltage drop of V or 0 and the second supply uses diodes back to back to develop a voltage drop which can be stepped up and rectified to a DC voltage for powering the digital light control.

Abstract: A mains protection device for a.c. mains comprises a circuit for detecting whether or not the mains voltage is within an amplitude window. When the voltage goes above or below the window, the mains is disconnected from an appliance and when the voltage returns to within the window for a preset time, the mains is reconnected to the appliance.

Abstract: An auxiliary connector circuit is used within an electronic system (10) which comprises a plurality of removable circuit cards (14, 16, 18, 20, 22, 24, 26) which are mounted within a cabinet (12). Before the circuit card (16) is removed from the cabinet (12), a power cable (44) is connected by means of engaging a plug (46) to a socket (34). When this occurs a DATA OUT ENABLE signal at a line (65) drives three-state devices (86, 88, 90, 92, 94, 96, 98 and 100) to a high impedance state to isolate a memory array (78) from a data bus (102). This high impedance prevents any transients from being transmitted through the data bus (102) when the card (16) is removed from the cabinet (12). After the card (16) is removed from the cabinet (12), the power cable (44) can be disconnected from the card (16) or the card (16) can be tested to evaluate the components mounted on the card (16).

Abstract: The invention electronically identifies whether a computer module board is placed in the correct mechanical slot in a computer frame. A conductive line is connected to at least one electronic connector location in each mechanical slot in a computer frame. A computer module has open circuit electrical connectors which if put in the correct slot will mate with the locations in the slot in the frame which are connected to the conductive line. The other electrical connections which are used for identification are connected to a ground plane in the computer module board. A voltage source is connected through a resistor to a conductive line in the computer frame producing a high signal. If any computer module board engaged in a slot of the computer frame is in the incorrect slot, a low signal will be caused indicating the fault. The fault signal will be supplied to a power supply controller which prevents operating power from being provided to the computer boards.

Abstract: The timing controller includes a triac, a receptacle, and an AC wall outlet coupled in series. A sensor is coupled across the receptacle to sense when a lamp plugged therein is turned on or off. A microprocessor is coupled to the sensor circuit and stores each time the lamp is turned on and each time it is turned off. After twenty-four hours have lapsed, the microprocessor operates the electronic switch in accordance with the stored temporary program to turn the lamp on and off at the same times on each succeeding day. In the event of a power failure, the subsequent reapplication of power will cause the microprocessor to turn the lamp on and off for four-hour periods.

Abstract: A trigger switch for use with hand held power tools includes a trigger which is movable in response to finger pressure thereon. A pair of normally open switch contacts are closed when finger pressure in excess of a first threshold pressure is applied to the trigger. In the event the applied finger pressure exceeds a second, greater threshold pressure, the switch contacts are opened to deactuate the tool. An insulating member shields the switch contacts when the second threshold pressure is exceeded to prevent closure of the contacts upon release of the trigger. A second set of switch contacts, closable in response to finger pressure in excess of the second threshold, may be provided to control actuation of an electrical tool brake mechanism.

Abstract: A solid state power controller including a switching device which has a first impedance in an ON state and a second, higher impedance in an OFF state is provided with a leakage current shunt circuit. The solid state power controller includes a control circuit for turning the switching device on and off. This control circuit is operatively associated with a shunt circuit operating means which turns the shunt circuit on following a transition of the switching device from an ON state to an OFF state and which renders the shunt circuit inoperative prior to a transition of the switching device from an OFF state to an ON state. The shunt circuit thereby acts to clamp the voltage appearing at a pair of solid state power controller load output terminals.

Abstract: A start switch is provided for a single phase AC motor having a start winding and a start capacitor connected in series with the start winding and a main winding connected in parallel with the start winding and start capacitor. The AC motor is connectable with an AC power source in order to supply AC main winding voltage to the main winding and AC start winding voltage to the start winding. The start switch includes conductors connected with the main winding for sensing the AC main winding voltage and conductors connected with the start winding for sensing the AC start winding voltage. Phase sensor circuitry is employed to sense a difference in voltage phase between the start winding voltage and the main winding voltage. Detector circuitry is connected with the phase sensor circuitry to detect when the difference in the voltage phase reaches a threshold.

Abstract: A programmable quartz clock has an actuator means operable to engage with and to actuate a control lever of a mechanically actuatable entity, such as a slide switch or a wall switch, thereby to effect programmed actuation of this entity.The clock comprises a small battery, a miniature electric motor with a gear/linkage mechanism operable to engage with and to move said lever, integrated circuit means, a quartz element, numeric display means, and programming means receptive of programming instructions by way of programming input keys.Once programmed by way of the input keys, the clock is operative to cause the electric motor to operate in such manner as to move the control lever in accordance with the keyed-in program. In its anticipated most common operating mode, which includes an average total of six actuations per day, the small battery will last for years before needing replacement.

Abstract: An electronic control device enables a load to be separated from a power supply network for a time corresponding to the period which the load would cause a major disturbance in the network due to the state of the load at the time of a temporary main outage. The electric circuit control device comprises a first, normally open controlled switch (2) connected in the electric circuit, a second, normally closed, controlled switch (4) shunted with the first controlled switch (2), a power supply network (6) for supplying power to the control device, first time delay control network (17) connected to the first controlled switch (2), second time delay control network (30) connected to the second controlled switch (4) and memory network (41) connected to the second controlled switch (4), the time delay of the first control network (17) being at most equal to the time delay of the second control network (30).

Abstract: The invention relates to a changeover discharge circuit for an electronic switching circuit of the type having a semiconductor switching element in series with a DC source and an inductive load. Initiation of the discharge current of a discharge capacitor is delayed upon the switching on of the switching element until the substantial termination of the load current by a commutation choke coil and a recovery diode in shunt with the load.

Abstract: A power supply control device is usable in a battery-driven electronic device, in which a power down mode is adopted when the battery is mounted.

Abstract: A technique is disclosed for protecting against electrocution or shock resulting from contacting an exposed conductor which is connected to a power supply. The flow of power to the conductor, whether DC or AC, is periodically interrupted and during the interruption, contact between a body and the conductor is sensed. If the body is not contacting the conductor, power is restored, but if the body is contacting, the interruption is maintained. The circuit may also distinguish between contact with the body and contact with an electrical device which receives power from the conductor. The electrical device includes a barrier circuit, such as a diode, which switches to an electrical state, such as a high impedance state, when power is interrupted. Because the electrical characteristics of the barrier circuit, such as its capacitance, differ from those of a body, the circuit is able to detect contact with a body.

Abstract: A power management system for a recreational vehicle operates automatically to disconnect a major electrical appliance, such as an air conditioner, heater or water heater, from power when the current drawn by additional appliances exceeds a preset current threshold. When the current drawn by these additional appliances falls below the threshold, the major appliance is automatically reconnected. A preferred embodiment of this invention operates to alternate between two or more air conditioners, heaters, or the like, to ensure that only one is connected to power at any given time, but that both are activated alternately and in sequence to provide efficient use of both air conditioners. In addition, preferred embodiments of this invention operate to interrupt operation of the air conditioners whenever the power voltage falls excessively low, and to ensure at least a preselected time delay between the time an air conditioner is stopped and restarted.

Abstract: Automatic opening/closing control of side windows of a vehicle. An electronic control device mainly composed of a microcomputer reads respective time-serial opening/closing patterns of key switches. These time-serial opening/closing patterns are respectively allocated to commands sent to the electronic control device. The electronic control device controls driving of the opening/closing mechanism for each side window in accordance with the commands. The electronic control device further effects overload detection of the opening/closing mechanism, limit position detection in movement thereof as well as arithmetic operation of the actual position, and then stops driving of the opening/closing mechanism at the time when the opening/closing mechanism undergoes overload and at the time when the actual position reaches the goal position.

Abstract: An electric power unit capable of operating from different AC input power source voltages in which changes in the AC input voltage are compensated for automatically and rapidly. The power unit includes a rectifier circuit having both a voltage-multiplying rectification function and a non-voltage-multiplying rectification function. A switching circuit is provided for selecting as the operating rectification function one of the voltage-multiplying rectification function and the non-voltage-multiplying rectification function. A switching control circuit, operating with the AC input to the rectifier circuit as a reference potential, controls the switching circuit according to the value of the AC input voltage. An auxiliary power source establishes a voltage for powering the switching control circuit before the operation of the switching control circuit to select the rectification function is effected.

Abstract: A safety receptacle or contact system for use at the outlet end of an electric supply line and for connection of at least one attachment plug that has at least two contact pins; the receptacle comprises a base plate; at least two connector ends supported by the base plate; a lid or cover housing including a front plate having at least two openings for receiving the plug pins and for guiding them into contact with the connector ends; an electrical circuit associated with the receptacle for controlled connection of the connector ends with the electric supply line and comprising a relay for breaking contact between the connector ends and the supply line when the two plug pins are withdrawn from the receptacle; and a light barrier connected with the relay for control thereof and arranged for operation in response to connection or non-connection of the plug with the receptacle.

Abstract: This invention is an electronic lamp control circuit for connection between a lamp bulb and a wall receptacle controlled by a wall switch. The lamp control circuit includes switching circuitry which permits complete control of the lamp from either the wall switch or a switch included in the lamp control circuit. The lamp control circuit permits a user to turn off the lamp by actuating the wall switch and to later turn on the lamp by actuating the lamp control switch and to turn off the lamp with the lamp control switch and later turn on the lamp using only the wall switch.

Abstract: The circuit for controlling the stopping of equipment comprises a switch with two contacts and with a pushbutton able to bring about the switching of the contacts into an open position and a closed position. The circuit comprises a supplementary member which functions like the pushbutton and is controlled by a relay in series with one of the contacts of the switch, this relay being responsive to a remote control device.

Abstract: A solid state remote monitoring transmitter which transmits a 40 bit word that contains status information about a transformer via the secondary of a power distribution network to a central receiver associated with the primary (feeder) cable supplying the transformer. A program card specifies the carrier signal frequency and the identification of the transmitter. Multiple analog inputs are switched through a multiplexer to an A/D converter, the output of which is stored in a shift register to form the 40-bit word. The word is DPSK-coded by clock pulses in synchronism to the 60 Hz zero crossings of the AC power source and amplified by an unregulated power supply which is also powered by the AC power source. The phase transitions of th DPSK-coded word occur at the zero crossings diminishing any transients in the transmitter circuitry which would be caused by the phase transitions.

Abstract: A solid state switch assembly including a circular array of three electrode semiconductors (26) with a control semiconductor (46) disposed centrally of the array. First and second buses (12 and 30) are in electrical contact with the semiconductors (26). A spider-like conductor (60) has legs (62) extending to respective control electrodes of the semiconductors (26) in the circular array and a central base (64) in circuit with the control semiconductor (46).

Abstract: An electrical control module to provide both remote and wall-operated switching for an electrical device such as a lamp. The control module includes a receptacle for the lamp plug, a remote on/off switch and a plug for insertion into the outlet connected to the wall on/off switch for the lamp. A power input is provided for the control module either from the wall outlet receptacle or from a separate receptacle. There are first and second relays within the control module which are effective to provide for independent on/off switching of the lamp by either the remote switch or the wall switch.

Abstract: A consumer electronics product such as a portable radio or combination radio/tape recorder having both primary and auxiliary loads is provided with power control apparatus for energizing both loads when connected to a source of a-c potential and energizing only the primary load when connected to a source of d-c potential. The control apparatus includes a solid state switching device in series with the auxiliary load, the switching device coupled to the output of the a-c source such that it is conductive only when a-c electric power is being supplied to drive the loads.

Abstract: A temperature controlled circuit including a thermistor located in one branch of a bridge circuit containing several resistors, an operational amplifier, all combined in such a manner that a resistor is inserted in parallel with the thermistor to lower its impedance. The branches of the bridge circuit are also arranged in such a way that three branches have a nominal resistance approximately equal to the resistance of the thermistor in parallel with its fixed resistance at room temperature, while the fourth leg on the branch in series with the parallel thermistor and resistance across the voltage source will have a resistance nominally in the range of one-third of the paralleled resistor and thermistor. The arrangement is such that most any thermistor can be utilized merely by changing its parallel resistance, and the operational amplifier will operate with the thermistor over a wide temperature range.

Abstract: A fully automatic programmable wall switch timer for controlling lighting circuits is described. The device provides user selected lighting circuit operation at predetermined event times, for predetermined event duration at said times, and at a selected light brightness or intensity level. The device is microprocessor controlled and is intended for installation in a standard wall switch box using existing wall switch plates. Included are a time of day and programming display and a three-way switch option. Separate switches are provided for isolating the unit from the power line, selecting lighting circuit operation, and advancing the display time. Additionally, various user programming modes are provided by operation of said switches singly and in conjunction with each other.

Abstract: A contactless relay wherein the application of an A.C. signal to the primary winding of a transformer is controlled by a command input, and the A.C. signal obtained from the secondary winding of the transformer is rectified into a D.C. signal by a rectifier circuit. The D.C. signal drives a transistor switching element for switching action. The switching element includes a single bipolar transistor, or a pair of bipolar transistors which can be connected in parallel to increase the current-carrying capacity of the relay. The output terminals of the relay can be rendered non-polar by constructing the relay of two bipolar transistors having commonly connected emitters and commonly connected bases.

Abstract: A dimmer switch and dimmer system is described in which dimming for the entire system is controlled from a single device while on/off switching is controlled by individual devices at multiple locations. The main dimming device contains an alternate action switching circuit for opening and closing the gate circuit of a controllably conductive device. Each of the remote location switching devices consists of respective low voltage switches, each operable to operate the alternate action switching circuit in the main dimmer device and are connected thereto by wiring which carries only signal level voltages and currents. Each remote switch may be a wall-mounted switch containing a single, relatively large area push button which momentarily closes a short movement, low activation force pair of contacts when the large area push button is depressed by pressure applied to any portion over its surface.

Abstract: A steering wheel switching circuit is provided which is capable of controlling component parts on a car body side through the use of a small quantity of coupling devices in cooperation with a controlling part by connecting a switching part installed on the steering wheel and two sets of series circuits installed on the car body part in parallel with a power supply. The switching portion includes a switch circuit having diodes electrically short-circuited across two terminals in both the positive and the negative direction. These two sets of series circuits have load resistances and switching elements with control terminals with the controlling part applying opposite polarity signals to the control terminals of the switching elements.

Abstract: An electrically powered hand tool, such as a staple gun, can employ an electrical driver, such as a solenoid, which is actuated by a trigger circuit in response to depression of a trigger on the handle of the device. The trigger circuit can include a circuit board dimensioned to fit into the handle of the staple gun, and having AC input leads. A circuit formed of conventional electronic components delivers a burst of power to output leads which are in turn connected to a driver solenoid. This circuit is actuated to deliver the power burst by opening of a switch formed of two switch members: one switch member has a first flexible resilient conductive leaf formed, e.g., of an alloy of copper, extending beyond an edge of the board; the other member has a flexible resilient leaf with a bent-in pointed end contacting a side of the first blade. These blades are biased against each other to form a normally-closed switch. When the first blade is moved in one direction, the switch opens.

Abstract: Automatic high insulation switch with low consumption level and small overall dimensions. The switch is associated with an apparatus for measuring very low currents (10.sup.-7 to 10.sup.-14 amperes) comprising an amplifier controlled by an input field effect transistor. The invention aims to switch on the amplifier's very high value resistors with the aid of magnetically controlled, flexible reed interrupters or switches, actuated by a permanent magnet, which is itself controlled by a conventional servomechanism having a motor and a potentiometer controlled by a microprocessor. Other interrupters ensure the protection of the transistor. The invention is more particularly used for measuring currents supplied by ionization chambers.

Abstract: Disclosed is a non-polarized, contactless relay constructed of electronic circuitry devoid of mechanical contacts but capable of performing the same function as a relay with such contacts. The relay includes a transformer, a control circuit for applying an oscillatory signal to the primary windings of the transformer in accordance with a command input, a rectifying circuit for rectifying A.C. power obtained from the secondary windings of the transformer in response to the oscillatory signal applied to the primary windings, a smoothing circuit which smooths the rectified output produced by the rectifying circuit for delivering D.C. power, and switching means composed of a pair of MOS-type field-effect transistors driven by the D.C. output of the smoothing circuit. The command input, namely "1" or "0" logic, applied to the control circuit results in the supply of the D.C.

Abstract: In a battery operated, remote transmitter for a consumer instrument, a microprocessor controls operation of the transmitter. The collector current path of a PNP on-off transistor is coupled between the battery and a voltage supply terminal of the microprocessor. To power up the microprocessor, a keyboard switch in the transmitter is depressed in order to ground the base of the on-off transistor and turn on the transistor. An NPN transistor forms a latch with the PNP transistor to maintain the on-off transistor conductive. After completion of the transmitter signaling, the microprocessor switches an output port to the ground state. The output port is coupled to the base of the NPN transistor and bypasses current therefrom to initiate the regenerative deactivation of the latch. With the latch deactivated, conduction of the on-off transistor is cut off. The voltage supply terminal of the microprocessor is disconnected from the battery to power down the remote transmitter.

Abstract: In a battery operated, remote transmitter for a consumer instrument, a microprocessor controls operation of the transmitter. The collector current path of an on-off transistor is coupled between the battery and a voltage supply terminal of the microprocessor. To power up the microprocessor, a keyboard switch in the transmitter is depressed to activate a separate latch that is coupled to the base of the on-off transistor. Base current flows to the latch to turn on the transistor and apply the battery voltage to the voltage supply terminal of the microprocessor. After completion of the transmitter signaling, the microprocessor switches an output port to the ground state. The output port is coupled to a control terminal of the latch and bypasses holding current from a portion of the latch to initiate the regenerative deactivation of the latch. With the latch deactivated, conduction of the on-off transistor is cut off.

Abstract: Apparatus for switching alternating current from a power source to a load for substantially all of one selected half-cycle, but not before at least one full cycle after the apparatus receives an operator command to switch the current, includes a mechanical switch for commanding the apparatus at an arbitrary time to switch the current. Electrical control devices produce a control output during a portion of the selected half-cycle. A second switch device, such as an SCR, responsive to the control output switches the current to the load during the selected half-cycle. The control output is turned off before the end of the half-cycle and is not produced again until the mechanical switch is released and provides another command to switch the current.

Abstract: A power controller determines which of a plurality of possible input voltages is present and configures a load to operate at that present input voltage.