A driver for a switch in a GIS (Gas Insulation Switchgear) includes a motor, a shaft connected with a moving contact of the switch, a gear connected with one terminal of the shaft and configured to transfer power of the motor to cause the shaft to reciprocate the moving contact through the shaft, a cam spline combined with the shaft and spaced apart from the gear, and a micro-switch connected with the cam spline and configured to control an operation of the motor.

A three-phase disconnect switch for a power distribution system that supplies three-phase power from a source through a main circuit breaker to multiple three-phase feeder circuits, includes three pairs of contacts adapted for connection to the three phase lines of a selected one of the feeder circuits for opening and closing each of the phase lines, and a movable actuator associated with the three pairs of contacts and responsive to a signal indicating the occurrence of an arcing fault in the selected feeder circuit for initially creating a short circuit across the three phase lines of the feeder circuit and then opening the contacts.

The invention relates to a medium voltage switchgear assembly which comprises at least one disconnector and whose drive unit is disposed inside or outside a gas chamber according to the generic part of claim 1. In order to further develop a switchgear assembly of the generic type so as to render the same more compact and more functional, the disconnector is embodied as a three-position vacuum chamber switch.

A switching apparatus includes: a vacuum valve which houses a fixed side electrode fixed to a fixed current-carrying shaft and a movable side electrode fixed to a movable current-carrying shaft coaxially arranged with the fixed current-carrying shaft in face-to-face relation to the fixed side electrode; and a buffering mechanism which is coaxially disposed with the fixed current-carrying shaft on the fixed side of the vacuum valve and reduces a collision load at the time when the movable side electrode is close contact with the fixed side electrode.

The switchgear includes a vacuum circuit breaker that is disposed in a circuit breaker chamber compartmented by a grounded metal plate, a busbar that is disposed in a busbar chamber and connected to the vacuum circuit breaker through a conductor, a cable that is disposed in a cable chamber and connected at one end to a load side, and a grounding device that is operated by a grounding device actuator disposed in a grounding device actuator chamber, connected to the vacuum circuit breaker through a conductor, and connected to the other end of the cable. The busbar is formed by a solid-insulated busbar. The conductor connecting the vacuum circuit breaker to the busbar and the conductor connecting the vacuum circuit breaker to the grounding device are both formed by a solid-insulated conductor. The circuit breaker chamber and the grounding device have a sealed structure.

An electric switch for application to high- and very high-voltage circuit breakers and switches comprising a flexible toroidal helical spring (8) placed in a groove of a control rod (1) carrying a movable resistance-insertion contact (2), and springs (4) placed about the movable resistance-insertion contact to cause the springs to be compressed until a certain value is reached, at which value the movable resistance-insertion contact causes the flexible toroidal helical spring (8) to deform under pressure enabling the movable resistance-insertion contact (2) to be withdrawn. Among other uses, the switch is suitable for use in a resistance-inserting device that does not need additional mechanical moving parts. For application to high- and very high-voltage circuit breakers and switches.

A sealed solenoid, magnetically operated electric power switch is suitable for use as capacitor, line and load switch operating at transmission and distribution voltages that includes no dynamically moving seals through the sealed container housing the contactor portion of the switch. The sealed solenoid switch includes a magnetically operated drive system with an actuator that magnetically couples across the container wall to avoid the use of a moving or sliding seal as part of the drive system. The sealed solenoid switch may also include a ballast resistor and resistor contact located inside the sealed container to avoid another seal as part of the ballast system. A magnetic latch holds the switch in a closed position, and a spring holds the switch in the closed position, to avoid the need for an energizing current to maintain the switch in either position.

A switch unit includes a plurality of switches, which are linearly disposed. The movable electrode in one switch and the fixed electrode in another switch are electrically connected to each other.

Provided is a sector gear including: a drive gear having a drive part that forms a part of a circle and has a plurality of teeth and a non-drive part that forms a remaining part of the circle and provides a non-contact angle of at least approximately 90 degrees; first and second movers forming a disconnector and a grounded breaking switch, respectively; and first and second driven gears engaged with the drive gear and respectively engaged with the first and second movers and configured to make the first mover or the second mover operate in conjunction with the drive part of the drive gear according to a direction of rotation of the drive gear, wherein an intermediate angle between the first and second movers is between approximately 90-135 degrees. The present invention can reduce the size of the gas-insulated switchgear having the sector gear.

A gas insulated switchgear includes an enclosure, a first fixed conductor, one side of the first fixed conductor being bent at a right angle and another side of the first fixed conductor being fixed on one side of the enclosure, a second fixed conductor configured to be spaced apart from the first fixed conductor and configured to be fixed on another side of the enclosure, a screw configured to form an axis on inner of the enclosure and being spaced apart from the first and second fixed conductors and a movable conductor configured to move along the axis through a rotation of the screw, one side of the movable conductor being in contact with the second fixed conductor.

An exemplary medium or high voltage switch has a first set of contact elements and a second set of contact elements. Each contact element includes an insulating carrier carrying conducting elements. In the closed state of the switch, the conducting elements align to form one or more current paths between terminals of the switch along an axial direction. For opening the switch, the contact elements are mutually displaced by means of one or two drives along a direction perpendicular to the axial direction. The switching arrangement is arranged in a fluid-tight housing in a gas of elevated pressure or in a liquid. The switch has a high voltage withstand capability and fast switching times.

A method of operating a switched-mode power supply (SMPS) for supplying power to a load circuit, which draws a supply current that varies with an input signal to the load circuit is disclosed. The method comprises monitoring the input signal and controlling the amount of accumulated energy transferred for consumption by the load circuit, in use, in accordance with the input signal.

Systems and methods are provided for generating an amplitude modulation signal to a switchmode power amplifier. A DC to DC switch is configured to receive a DC input voltage and to provide a DC output voltage. A low dropout regulator is configured to provide the amplitude modulation signal according to a modulation control signal received by the low dropout regulator. A control circuit is configured to establish a nominal operating power level for the power amplifier via the amplitude modulation signal and to maintain a minimum voltage difference between the DC output voltage and the low dropout regulator output. A modulator control circuit is configured to provide the modulation control signal to the low dropout regulator. The modulator control circuit provides the transition from a high amplitude to a low amplitude and a transition from the low amplitude to the high amplitude at configurable first and second slopes, respectively.

A transceiver includes: a power amplifying circuit arranged to generate differential output signals during a transmitting mode of the transceiver; a balance-unbalance circuit arranged to convert the differential output signals into a single-ended output signal; a switchable matching circuit arranged to receive the single-ended output signal on a signal port of the transceiver during the transmitting mode, and to convert a single-ended receiving signal on the signal port into a single-ended input signal during a receiving mode of the transceiver; and a low-noise amplifying circuit arranged to convert the single-ended input signal into a low-noise input signal during the receiving mode. The power amplifying circuit, the Balun, the switchable matching circuit, and the low-noise amplifying circuit are configured as a single chip.

A voltage converter can be switched among two or more modes to produce an output voltage tracking a reference voltage that can be of an intermediate level between discrete levels corresponding to the modes. One or more voltages generated from a power supply voltage, such as a battery voltage, can be compared with the reference voltage to determine whether to adjust the mode. The reference voltage can be independent of the power supply voltage.

The present invention relates to a position sensor and limit switch apparatus for an actuator. The actuator has a cylinder and a piston with at least one magnetized portion reciprocatingly disposed within the cylinder. The apparatus includes an elongate housing aligned parallel with the cylinder. A magnetostrictive linear displacement transducer is disposed within the housing for sensing the position of the at least one magnetized portion. The apparatus includes a switch means responsive to the transducer for operatively interrupting actuation of the piston upon the at least one magnetized portion reaching a limit position.

A method of operating a switching power converter may include determining an average value of a measured parameter for substantially each switching cycle, and adjusting a control parameter during substantially each switching cycle in response to a corresponding one of the average values. In one embodiment, the control parameter comprises a switch duty cycle, and the measured parameter comprises an output current. Determining the average value of the measured parameter may include obtaining a first sample of the measured parameter during a switching cycle, and calculating the average value of the measured parameter during the switching cycle in response to the first sample.

A method for controlling voltage crossing a power switch of a switched-mode power converter includes the steps of: controlling a switch frequency of the power switch of the switched-mode power converter to a first frequency as activating the switched-mode power converter; and then changing the switch frequency of the power switch to a second frequency after the switched-mode power converter is activated for a predetermined time; wherein the first frequency is lower than the second frequency.

In one implementation, a modular power converter having a reduced switching loss includes a package, a field-effect transistor (FET) including a gate terminal, a drain terminal, and a source terminal, and fabricated on a semiconductor die situated inside the package, and a driver circuit inside the package. The driver circuit is configured to drive the gate terminal of the FET. The driver circuit is further configured to sample a drain-to-source voltage (VDS) of the FET directly from the drain terminal and the source terminal, thereby enabling the reduced switching loss.

A “windowless” H-bridge buck-boost switching converter includes a regulation circuit with an error amplifier which produces a ‘comp’ signal, a comparison circuit which compares ‘comp’ with a ‘ramp’ signal, and logic circuitry which receives the comparison circuit output and a mode control signal indicating whether the converter is to operate in buck mode or boost mode and operates the primary or secondary switching elements to produce the desired output voltage in buck or boost mode, respectively. A ‘ramp’ signal generation circuit operates to shift the ‘ramp’ signal up by a voltage Vslp(p−p)+Vhys when transitioning from buck to boost mode, and to shift ‘ramp’ back down by Vslp(p−p)+Vhys when transitioning from boost to buck mode, thereby enabling the converter to operate in buck mode or boost mode only, with no need for an intermediate buck-boost region.

A disclosed switching regulator includes a speed-up circuit for speeding up an operation of an error amplifier circuit during the time starting from when a switching element is turned OFF based on an output of an abnormality detection circuit, or starting from a fixed period of time after the switching element is turned OFF based on the output of the abnormality detection circuit, until the next time the switching element is again turned OFF based on an output of a PWM comparison circuit.

A switching power converter includes a voltage source that provides an input voltage Vin to an unregulated DC/DC converter stage and at least one buck-boost converter stage to produce a desired output voltage Vout. The unregulated DC/DC converter stage is adapted to provide an isolated voltage to the at least one regulated buck-boost converter stage, wherein the unregulated DC/DC converter stage comprises a transformer having a primary winding and at least one secondary winding and at least one switching element coupled to the primary winding. The at least one buck-boost converter stage is arranged to operate in a buck mode, boost mode or buck-boost mode in response to a mode selection signal from a mode selection module. By influencing the pulse width modulation output power controller the at least one buck-boost converter stage is arranged to produce one or multiple output voltages.

A constant on-time switching converter includes a switching circuit, an on-time control circuit, a comparing circuit and a logic circuit. The switching circuit has a first switch and is configured to provide an output voltage to a load. The on-time control circuit generates an on-time control signal to control the on-time of the first switch. The comparing circuit compares the output voltage of the switching circuit with a reference signal and generates a comparison signal. The logic circuit generates a control signal to control the first switch based on the on-time control signal and the comparison signal. When the switching frequency of the switching circuit approaches an audible range, the switching converter enters into a sleep mode, the on-time control signal is reduced to increase the switching frequency of the switching circuit.

An electronic apparatus includes a switching element which has a control terminal and is driven by controlling voltage of the control terminal, a driving power supply circuit which supplies voltage required for driving the switching element, an on-driving circuit which is connected to the driving power supply circuit and the control terminal of the switching element and is supplied with voltage from the driving power supply circuit, and which applies a constant current to the control terminal of the switching element to charge the control terminal, thereby turning on the switching element, and at least one diode which is connected between the on-driving circuit and the control terminal of the switching element. The on-driving circuit applies a constant current to the control terminal of the switching element through the diode.

A bridge-less step-up switching power supply device includes (i) a first and a second reactor having: a first and a second main winding connected to a first and a second input terminal, respectively; and a first and a second auxiliary winding magnetically coupled to the first main winding and connected to the first and second main windings, the first and second auxiliary windings having a first and a second leakage inductance, respectively; (ii) a first and a second diode connected between the first and second auxiliary windings and a first output terminal, respectively; (iii) a first capacitor connected between the first output terminal and a second output terminal; (iv) a second capacitor connected between a connection point of a third switch and a fourth switch, and the first output terminal; and (v) a controller for controlling turning on/off of first to fourth switches.

A switched mode power supply provides a reduction of switching losses and increased efficiency. The switched mode power supply includes a first switch coupled to an input terminal configured to receive an input voltage, a second switch, an inductor and an output capacitor. The first switch and the second switch are coupled together at a node, the inductor is coupled between the node and an output terminal, and the output capacitor is coupled to the output terminal. The switched mode power supply further includes a transformer coupled between a control input of the first switch and the node and a pulse generator connected to a control input of the second switch. Further, the transformer includes at most two windings, in particular a primary winding and a secondary winding which are not directly connected to each other.

A mode controller shifts, along with increase in an electric power in first and second of chopper circuits and, operation modes of the first and the second of the chopper circuits from a first mode to a third mode via a second mode. An operation controller causes, in the first mode, the first of chopper circuit to perform an chopping operation, and the second of chopper circuit to suspend the chopping operation, in the second mode, causes the first and the second of chopper circuits to alternatively perform the chopping operations, and in the third mode causes both of the first and the second of chopper circuits to perform the chopping operations.

To improve operability of a switching operation and locking operation of an operation pattern switching valve for switching the operation pattern of controlling devices for actuator control valves. An operation pattern switching device has a rotating operation member that rotates around a shaft center of a rotating support shaft, and thereby performs a switching operation of the operation pattern switching valve; and an operation lever that is provided rotatably integrally with the rotating operation member and performs a rotating operation of the rotating operation member. The rotating support shaft is, at each pattern switching position of the operation pattern switching valve, in a circumferential direction, provided with a plurality of lock engagement parts each with which the operation lever engages. The operation lever moves in a direction orthogonal to the shaft center of the rotating support shaft, and be thereby made engageable/removable with/from each of the lock engagement parts.

A switching valve contains a sleeve member, a plug member, and a damping spring. The sleeve member includes a watering segment, a spraying segment, a peripheral fence, a side fence, a channel, a first watering chamber, and a second watering chamber. The peripheral fence has a first valve seat, a second valve seat, and at least one set of inlet. The first valve seat has a conical first closing face and a plurality of stop blocks. The second valve seat has a conical second closing face. The plug member includes a first sealing portion, a second sealing portion, and guiding ribs. The first sealing portion has a first ring, and the second sealing portion has a second ring. Each guiding rib has a guide face, and between any two adjacent guiding ribs is defined a slot. The damping spring is mounted between the side fence and the plug member.

A mechanism for coupling a switch point to a point detector box having a point detector bar includes a first portion structured to be slidably coupled to the point detector bar and a second portion structured to be slidably coupled to the switch point.

Aspects of the invention provide a transport system powered by short block Linear Synchronous Motors (LSMs). The use of short blocks allows vehicles to move under precise control even when they are in close proximity to each other. The design allows the vehicles to be propelled and guided while negotiating sharp turns and negotiating merge and diverge switches. A coreless LSM can be used to create propulsive force without attractive force so as to allow a relatively high drag vehicle suspension, such as a vehicle sliding on a smooth surface. Further aspects of the invention provide a switching member that is selectively moveable relative to a guideway in order to change a magnetic force acting on the vehicle transverse to a direction of motion of the vehicle.

The invention provides in some aspects a transport system comprising a guideway with a plurality of propulsion coils disposed along a region in which one or more vehicles are to be propelled. One or more vehicles are disposed on the guideway, each including a magnetic flux source. The guideway has one or more running surfaces that support the vehicles and along which they roll or slide. Each vehicle can have a septum portion of narrowed cross-section that is coupled to one or more body portions of the vehicle. The guideway includes a diverge region that has a flipper and an extension of the running surface at a vertex of the diverge. The flipper initiates switching of vehicle direction at a diverge by exerting a laterally directed force thereon.

A hand shower has outer housing including a first housing part and a second housing part, is disposed in the interior of the outer housing. The first housing part is produced by dual-component injection molding and has a support formed from a hard component. Alongside the switching device, this support is provided with a passage. A soft component, injected onto the outer side of the support covers the passage in a membrane-like manner. The membrane region of the soft component is elastically deformable to allow the switching device to be operated from the surroundings.

The invention relates to a portable, handheld work apparatus such as a trimmer, a cut-off machine, a chain saw or the like, having a motor (5, 33) to drive a rotating, exchangeable work tool (13). A control unit (15) serves to control the operation of the motor (5, 33). The control unit (15) determines the rotational speed (n) and/or the power (P) of the motor (5, 33). According to the invention, the motor (5, 33) can be operated in a first operating mode (I) with reduced rotational speed (n0) and/or power (P0) and in at least a second operating mode (II) with an increased rotational speed (n1) and/or power (P1). In dependence on a release signal, the control uses exclusively the first operating mode (I) for a limited operation and the second operating mode (II) for an expanded operation.

A switchbox for monitoring the position of a manual quarter-turn valve has a housing mountable to the valve to be monitored/controlled. A handle-driven shaft extends through the housing, with one end of the shaft couplable to the valve stem such that movement of the shaft moves the valve stem. One or more shaft position sensor switches interact with a cam on the shaft to signal shaft position and/or provide control signals. A plate coupled to the shaft articulates within a recess on the surface of the switchbox to limit motion of the valve to an operable range, such as between full ON and full OFF. The switchbox has a pair of lock tabs with lock apertures. A lock aperture in the plate is alignable with the lock tab apertures to receive a pin or padlock for locking the valve in a selected position. A potentiometer can be utilized in place of a switch as a shaft position sensor. The switchbox may be used with an original or new handle and may feature detents to allow a range of valve settings.

A switchbox for monitoring the position of a manual quarter-turn valve has a housing mountable to the valve to be monitored/controlled. A handle-driven shaft extends through the housing, with one end of the shaft couplable to the valve stem such that movement of the shaft moves the valve stem. One or more shaft position sensor switches interact with a cam on the shaft to signal shaft position and/or provide control signals. A plate coupled to the shaft articulates within a recess on the surface of the switchbox to limit motion of the valve to an operable range, such as between full ON and full OFF. The switchbox has a pair of lock tabs with lock apertures. A lock aperture in the plate is alignable with the lock tab apertures to receive a pin or padlock for locking the valve in a selected position. A potentiometer can be utilized in place of a switch as a shaft position sensor. The switchbox may be used with an original or new handle and may feature detents to allow a range of valve settings.

An interconnect switch is provided including switching logic executable to facilitate a Peripheral Component Interconnect Express (PCIe)-based interconnect, and further including a control host embedded in the switch to provide one or more enhanced routing capabilities. The control host includes a processor device, memory, and software executable by the processor device to process traffic received at one or more ports of the switch to redirect at least a portion of the traffic to provide the one or more enhanced routing capabilities.

The present application relates to a serial data communications switching device and a method of operating the serial data communications switching device. The serial data communications switching device comprises one host port for connecting to a host device; a plurality of client ports each for connecting to one of a plurality of client devices; an arbiter configured to arbitrate the permission to send a message sequence between the plurality of the client devices according to an arbitration scheme; and a TX flow analyzer adapted to detect a client transmission received at one of the client port from a current client device currently having granted the permission and to instruct the arbiter to maintain the granted permission for the current client device for the ongoing client transmission.

A method of switching an apparatus state of a first apparatus having a first universal serial bus (USB) interface connected via a connecting wire with a second USB interface of a second apparatus is provided. The method may include receiving a state switching instruction, setting a level of a configuration channel (CC) in a USB interface circuit corresponding to the first USB interface from a first high level to a first low level via a logic controller of the first apparatus when the state switching instruction instructs the first apparatus to perform a master-to-slave switch, and setting the level of the CC in the USB interface circuit corresponding to the first USB interface from the first low level to the first high level via the logic controller of the first apparatus when the state switching instruction instructs the first apparatus to perform a slave-to-master switch.

Methods, systems, and apparatus, including computer programs encoded on computer storage media, for storing an address in a memory of a switch. One of the systems includes a switch that receives packets from and delivers packets to devices connected to a bus without any components on the bus between the switch and each of the devices, a memory integrated into the switch to store a mapping of virtual addresses to physical addresses, and a storage medium integrated into the switch storing instructions executable by the switch to cause the switch to perform operations including receiving a response to an address translation request for a device connected to the switch by the bus, the response including a mapping of a virtual address to a physical address, and storing, in the memory, the mapping of the virtual address to the physical address in response to receiving the response.

A remote resource access method and a switching device are provided. According to the remote resource access method, when a computer system access the remote physical resource device, after obtaining a first access message, including a virtual address of a virtual resource device, from a computing node in the computer system, the switching device converts the first access message into a second access message based on a physical address of a physical resource device corresponding to the virtual address of the virtual resource device. Then, the switching device sends the second access message to the remote physical resource device corresponding to the physical address using a network, thereby implementing the data transmission between the local computer system and the remote physical resource device.

A new multifunctional, thermoelastic cellular structure is described. The new structure provides tunable thermal transport behaviors particularly important for thermal switching. In its simplest example embodiment of a single or unit cell, opposing bimetallic elements bend in response to temperature changes and, below a tunable switching temperature, are separated in an open or insulating position and, at and above the switching temperature, bend to come into contact in a closed or conducting position. Multiple cells are combined in different lattice arrays to create structures that are both switchable and load bearing. The cells can be switched by both temperature and other external fields.

A printing device includes a roller; a stepper motor; a head; and a controller, The roller is for conveying a printing medium in a conveying direction. The stepper motor is configured to rotate in synchronization with a pulse signal and rotate the roller. The head is configured to perform printing on the printing medium conveyed by the roller. The controller is configured to perform: decelerating the stepper motor from a first speed to a second speed; identifying a rotational speed of the stepper motor during deceleration of the stepper motor; performing synchronous printing in which the head is driven at timing in synchronization with the pulse signal when the rotational speed is greater than or equal to a prescribed speed; and performing timer printing in which the head is driven at a prescribed period when the rotational speed is less than the prescribed speed.

Nail gel curing devices emitting ultraviolet light, as well as methods of their making and use are disclosed. The devices are useful for curing, inter alia, acrylic compositions, more particularly, acrylic nail gel compositions, and typically employ ultraviolet and/or visible light emitting diodes (“LED”) to cure such ultraviolet and/or visible light curable nail gel resins.

Threshold switching devices demonstrating transient current protection through both insulation and repair current mechanisms, including associated systems and methods, are provided and discussed.

A voltage-resistant switch is described. The switch comprises a signal input, a first FET transistor with a first channel with an extended drain and a first gate connector and a second FET transistor with a first channel with an extended drain and a second gate connector. A control signal connector is connected with the first gate connector and with the second gate connector via a second node and with the first channel and the second channel via a second resistor, and a signal connector is connected with the second channel. The voltage-resistant switch can be switched on and off.

A high-voltage electronic switch includes first and second transistors defining a current flow path between an input and output of the switch. The transistors have a common point of the current flow path and a common control terminal. A control circuit includes a voltage line receiving a limit operating voltage and first and second branches coupled between the voltage line and the common point and common control terminal, respectively. Further transistors are activated, upon turning-off of the first and second transistors, for coupling the branches to the voltage line. The branches include a parallel connected resistor, diode, and string of diodes with opposite polarities. The diode of the first branch plus string of diodes of the second branch and diode of the second branch plus string of diodes of the first branch provide coupling paths between the voltage line and, respectively, the common point and common control terminal.

Capacitors connected between gate terminals of a plurality of parallel-connected power transistors are charged and discharged in each switching cycle to provide a plurality of power transistor control waveforms from a single gate driver waveform that equalize power losses/temperatures or steady-state currents among the plurality of power transistors. The capacitors are charged to different voltages by diverting current from one transistor driver by disabling another power transistor driver at different respective times in response to measured transient or steady state current or temperature or other operational parameter.

An integrated circuit includes a drive circuit with a first inverter circuit with a first transistor of a first conductivity type and a second transistor of a second conductivity type. The drains of the first and second transistors are connected. An output circuit is provided having a third transistor of the second conductivity with a gate connected to the drains of the first and second transistors. A capacitor is connected between the gate and a drain of the third transistor and has a capacitance greater than 0.5 pF and less than or equal to 3.0 pF. A gate width of the first transistor when divided by a gate width of the third transistor has a value of less than 1/100. The output circuit is configured to output a transmission signal from the drain of the third transistor.

The present invention is directed to an electronic switch device, the device including a housing assembly including a front cover assembly having a user accessible surface, a back body assembly, terminals configured to be coupled to an AC power source and the load; an antenna assembly including an antenna substrate disposed inside the housing assembly adjacent a portion of the front cover assembly, an antenna being disposed on the antenna substrate having a conductive grid structure; and a circuit assembly disposed inside the housing assembly coupled to the terminals, the circuit assembly comprising a printed circuit board, the printed circuit board including a ground plane, the circuit assembly being electrically connected to the antenna assembly via a conductor, the printed circuit board being separated from the antenna assembly by a predetermined distance, the circuit assembly including a relay switch having at least one solenoid winding connected to the circuit assembly and a set of contacts.