Apparatus for the detection of electromagnetic pulses and electrical disturbances resulting from the solar wind

Abstract

The apparatus detects complex time-varying electromagnetic disturbances resulting from a high altitude nuclear electromagnetic pulse (EMP) or solar wind. The device relies on a circuit (104, 1301) that monitors the incoming power lines (301, 401, 501) for sustained conducted electrical disturbances associated with the E3 phase of the EMP or solar wind. A separate circuit (105, 1302) monitors the power lines and the surrounding environment (503) for transient electromagnetic pulse disturbances associated with the E1 and E2 phases of the EMP. Upon detecting a sustained electrical disturbance or a transient electromagnetic pulse disturbance, the apparatus provides an audible alarm (608) and a discrete indicator signal (607) that may be used to cut off (702) or redirect the flow of power.

Description

[Technical field]

[0001] The present invention involves the detection of complex time-varying conductive and radiative disturbances resulting from electromagnetic pulses (EMP); solar wind producing solar flares, coronal mass ejections (CMEs) or geomagnetic disturbances; directed energy weapons; improper voltage regulation by power suppliers; or other events that manifest as voltage or current fluctuations in a conductive wire, trace, or circuit. [Background technology]

[0002] The lightning detection device monitors the surrounding environment for radiated electromagnetic disturbances having durations on the order of 50-200 microsecond timing that are indicative of a lightning event.

[0003] Another technology that may be considered equivalent is that of power line monitoring, which is used for the purpose of testing the incoming power line connections for undesirable conditions such as open grounds, reverse polarity, and steady high or low voltage levels. However, such devices do not have the capability to detect very short-term electromagnetic disturbances such as the conducted and radiated pulsed electromagnetic disturbances associated with EMP phases E1 and E2.

[0004] A few sophisticated methods have been proposed for detecting EMP occurrences, but these rely on the use of artificial intelligence, cutting edge signal processing, or multi-node networking of large infrastructures.

[0005] The present invention is illustrated by way of example and not by way of limitation in the accompanying drawings in which like reference numerals indicate like elements and in which elements in the accompanying drawings are illustrated for simplicity and clarity and, therefore, are not necessarily drawn to scale or complexity.

[0006] The details of the preferred embodiment will be more readily understood from the following detailed description when read in conjunction with the accompanying drawings. [Brief description of the drawings]

[0007] [Figure 1] A block diagram showing the housing, power conditioning circuitry, distributed protection circuitry, duration level detection circuitry, pulse detection circuitry, alarm circuitry, power disconnect switching circuitry, and optional on-board battery according to an embodiment of the present invention is shown. [Diagram 2] 1 shows a simplified schematic diagram illustrating a power conditioning circuit; this particular embodiment includes a fuse, a protection varistor, a series capacitor, a bridge rectifier, a Zener diode, and a linear regulator or switched converter in accordance with an embodiment of the present invention. [Diagram 3] 1 shows a simplified schematic diagram of a sustained level detection circuit; this particular embodiment includes a fuse, a protection varistor, a bridge rectifier, a voltage divider, a low pass filter, a transient voltage suppressor diode, a comparator input voltage divider, and a window comparator in accordance with an embodiment of the present invention. [Figure 4] 1 shows a simplified schematic diagram of an alternative embodiment of a persistent disturbance detection circuit; this particular embodiment includes a fuse, a protection varistor, a current limiting resistor, a persistent level threshold setting Zener diode, a reverse protection diode, an optocoupler, a bias resistor, a low pass filter, and a window comparator in accordance with an embodiment of the present invention. [Diagram 5] 1 shows a simplified schematic diagram of a transient disturbance detection circuit; this particular embodiment includes a fuse, a protection varistor, a high pass filter, an impedance matching filter, a bidirectional transient voltage suppression diode, a high speed monostable multivibrator pulse detector, a blocking diode, and a pull-down bias resistor in accordance with an embodiment of the present invention. [Figure 6] 1 shows a simplified schematic diagram of an alarm circuit; this particular embodiment includes a light emitting diode, a wired-or connected diode, a p-channel field effect transistor, an optional resettable latch, an audible alarm, and an output alarm signal in accordance with an embodiment of the present invention. [Figure 7]1 illustrates a block diagram of an alarm signal generated by a pulse detector and a sustained level detector according to an embodiment of the present invention, which may be used to cut off power or redirect power flow to an alternate path. [Figure 8] 1 shows a block diagram of one embodiment incorporated into a safety disconnect switch of a solar power system; in this embodiment, sustained level detector and pulse detector circuits monitor the photovoltaic and auxiliary power lines for disturbances indicative of EMP or solar wind; if such an event is detected, these detectors send an alarm to a controller or driver to force a disconnection of the photovoltaic. [Figure 9] 1 illustrates a conceptual diagram of a plug-in module that houses one embodiment in accordance with an embodiment of the present invention. [Figure 10] 1 shows a conceptual diagram of a battery powered key fob module incorporating one embodiment in accordance with an embodiment of the present invention. [Figure 11] 1 shows a plot characteristic of a high altitude nuclear electromagnetic pulse (EMP) waveform over a period of time. [Figure 12] Summarize the three waveform components of EMP, how they combine, and their typical duration. [Figure 13] We summarize how the three waveform components associated with the E1, E2, and E3 phases of an EMP are detected by the device's detection circuitry. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] The present invention is used to detect complex time-varying conductive and radioactive disturbances resulting from EMP or solar wind. The invention includes a circuit that continuously monitors the incoming power line to detect sustained level disturbances associated with E3, which have durations from seconds to hours, and a circuit that continuously monitors both the incoming power line and the surrounding environment to detect pulsed electromagnetic disturbances associated with E1 and E2, which have durations from nanoseconds to microseconds. When sustained level disturbances or pulsed disturbances are detected, visual alarms, audible alarms, and discrete indicating signals are generated. The signal alarm indicators may be used to notify a microcontroller or microprocessor of an alarm condition and to drive a power switching element, such as an electronically controlled circuit breaker or automatic transfer switch, for the purpose of automatically disconnecting power or redirecting the flow of power.

[0009] FIG. 1 shows a high level block diagram of a device including the present invention. The housing 101 may be shielded by a conductive barrier to suppress out-of-band electromagnetic energy that may cause false alarms. The power conditioning circuit 102 converts the input power into power with characteristics that are more easily used by the device's electronics. Such power conditioning may not be necessary in situations where the input power is already directly usable by the device's circuits. The protection circuits 103 are distributed throughout, allowing the device to successfully survive extreme electrical and electromagnetic transients, such as those resulting from EMP or solar wind. The protection circuits may consist of transient voltage suppressors, metal oxide varistors, gas discharge tubes, and other transient surge protection devices. The duration level detection circuit 104 monitors the input power line for voltage disturbances associated with the E3 phase having durations from seconds to hours. Similarly, the pulse detection circuit 105 monitors the input power line and the surrounding radiation environment for transient electromagnetic pulse disturbances associated with the E1 and E2 phases having durations from nanoseconds to microseconds. Both the sustained level detection circuit 104 and the pulse detection circuit 105 provide signals to an alarm circuit 106 indicating the detection of an EMP or solar wind related disturbance. The alarm circuit 106 then activates visual indicators, audible indicators, and discrete indication signals 107 that are used to notify external processing elements of the detection and may be used to trigger the disconnection or rerouting of power flow. An on-board battery 108 may be required in portable embodiments to provide power to the circuit elements.

[0010] FIG. 2 shows a simplified diagram of the power conditioning circuit 103. The power conditioning circuit converts the input power into power with characteristics that are more easily used by the device's electronics. The input power line may be fused 201 for safety and circuit protection. In addition, a metal-oxide varistor (MOV) or other transient protection device 202 may be used to limit input voltage disturbances that may result from EMP or solar wind. A bridge rectifier 203 is tapped on both sides to feed multiple nodes that are voltage limited by zener diodes 207 and ripple limited by capacitors 204. Power is then fed to a linear regulator, dc-dc converter, or other power conversion device 205 to provide the voltage, current, and performance characteristics required by the particular embodiment of the device. Capacitors 206 are used at the output of the power converter to ensure stability and ripple performance.

[0011] FIG. 3 illustrates a simplified diagram of a duration level detector 104 that monitors the input power line for voltage disturbances associated with the E3 phase. The duration level detector detects persistent electrical disturbances associated with at least one of the E3 phases of an electromagnetic pulse and solar wind. The duration level detector identifies the duration of the disturbance in the range of seconds to hours. The input may be fitted with a fuse 301 and may be protected from severe overvoltage conditions by a transient protection device 302. The input power line also features a series current limiting resistor 309. A bridge rectifier 303 is used in conjunction with a voltage divider 304 to rectify and scale the input voltage level. A low pass filter 305 passes durations in the range of seconds to hours by changing the level to a pseudo dc representation that is magnitude limited by a zener diode 306. One period of a 60 Hz waveform would be 16.6 ms, or one period of a 50 Hz waveform would be 20 ms, so the minimum end of the seconds to hours range may be selected at about 60 ms to about 100 ms. Five periods is believed to be sufficient to obtain a reasonable average of the signal, but other average durations would also work well. Resistor networks 307 are used to generate the inputs to overvoltage and undervoltage comparators 308. The resistors may be either fixed value or variable value (i.e. potentiometers), allowing the overvoltage and undervoltage trip points to be dynamically adjusted. The comparators may either have thresholds determined by supporting components, or be window comparators with predefined upper and lower trigger thresholds. The comparator outputs are fed directly to the alarm circuit.

[0012] FIG. 4 shows an alternative embodiment of the persistent disturbance detection circuit 104 (persistent level detector 104). The input power may be fitted with a fuse 401 and protected from severe overvoltage conditions by a transient protection device 402. Resistor 403 limits the current flowing into optocoupler 406 and may be placed before or after Zener diode 404. Zener diode 404 rectifies the input waveform and its turn-on voltage sets the minimum voltage at which optocoupler 406 activates. Diode 405 provides a reverse current path for the falling swing of the input voltage and helps protect the optocoupler. Optocoupler 406 converts the rectified input power signal into a pulse train whose pulse width is determined by the input voltage level, the waveform frequency, and a DC offset. Resistor 407 provides the necessary reference voltage to the optocoupler open collector output. A low pass filter 408 converts the pulse train into an analog signal representative of the input voltage level and persistent disturbances. This analog signal is compared to a set point in a comparator 409. The over-voltage and under-voltage detection signals are routed to an alarm circuit. The low pass filter and comparator may also be replaced by a microcontroller or microprocessor 410, which counts the number of pulses to determine the input voltage level and persistent disturbances.

[0013] FIG. 5 illustrates a simplified diagram of a pulse detector 105 that monitors the input power lines and the surrounding radiation environment for transient electromagnetic pulse disturbances associated with E1 and E2 phases. The pulse detector 105 detects transient electromagnetic pulse disturbances associated with E1 and E2 phases of at least one of electromagnetic pulses and solar wind. The pulse detector 105 is responsive to pulse disturbance durations in the nanosecond to microsecond range. The input may be fitted with a fuse 501 and protected from severe overvoltage conditions by a transient protection device 502. The combination of input power and conducted transient electromagnetic pulse disturbances are passed through a high pass filter 504. The high pass filter passes pulse disturbance durations in the nanosecond to microsecond range. Since EMP explosions have been measured to have a minimum E1 duration of about 20 nanoseconds, the minimum end of the nanosecond to microsecond range may be selected at about 10 nanoseconds or about 20 nanoseconds. The high pass filter 504 also removes undesired frequencies, including the frequencies of the power transfer. The antenna 503 is also connected to the input power node through an impedance matching filter 510 to maximize the power transfer of the radiated transient electromagnetic pulse disturbance. The antenna 503 has an electrical length with a resonant frequency that is tuned to the frequency spectrum of the transient electromagnetic pulse disturbance. The diode 505, working with the filter, acts as a differentiator and turns any "positive to negative" or "negative to positive" signal edge transitions into a sharp transient impulse. The bidirectional transient protection device 506 ensures that the impulse voltage level does not exceed the allowed input voltage range of the operational amplifier. The impulse is input to an extremely high bandwidth operational amplifier configured as a pulse detector, which is a monostable multivibrator 507. The pulse detector is a two-state pulse trigger detection circuit that uses edge, pulse, or impulse detection. An edge, pulse, or impulse at the input of the pulse detector causes its output to change state. A monostable multivibrator 507 is one preferred embodiment of a pulse detector.Alternative embodiments may be peak detection devices, high speed samplers, flip-flops, high gain comparators, and transient protection devices with very fast turn-on times. In a preferred embodiment, the output of the multivibrator is an active low pulse whose pulse width is set by the passive components of the multivibrator. A blocking diode 508 is used to prevent shared connections in the alarm circuit from affecting the performance of the multivibrator. Resistor 509 provides bias for the alarm circuit connections. The output is routed to the alarm circuit 106.

[0014] FIG. 6 shows a simplified diagram of the alarm circuit 106 powered by the sustained detection circuit 104 and the pulse detection circuit 105. The outputs of the sustained detection circuit and the pulse detection circuit are wire-OR'd together using diodes 601. A current limiting resistor 602 and a light emitting diode 603 provide visual alarms for sustained overvoltage, sustained undervoltage, and pulse disturbance conditions. Similarly, a light emitting diode circuit 609 provides a visual alarm for pulse detection. Resistor 604 along with resistor 509 are used to set the bias point at the gate of a p-channel MOSFET 606. The particular embodiment described in FIGS. 4 and 5 provides multiple different alarms for sustained undervoltage (three pulsed beeps), sustained overvoltage (continuous beep), and pulse disturbance (single beep of controlled duration). An in-line latch 605 may also be used to hold the state of the drive signal if desired. Such a latch would be either manually resettable or automatically resettable by an internal timer, not shown. A p-channel MOSFET 606 acts as a switch and provides power to an audible alarm 608 when a sustained or pulsed disturbance condition is detected. Additionally, an alarm signal 607 may be used as a trigger to turn off power or redirect the power flow to an alternative path. In various alternative embodiments, the discrete instruction signal may also be used to send a text or email or a TCP / IP signal to send an alarm, or connect to a Bluetooth or WiFi or cellular radio or 5G Internet of Things transceiver to transmit the alarm.

[0015] FIG. 7 shows a simplified block diagram of an apparatus 701 used to monitor an input power line for a surge protection device (SPD). In the event of a sustained level disturbance or a transient electromagnetic pulse disturbance related to an EMP or solar wind, the apparatus's internal alarm circuitry will activate visual and audible indicators. The apparatus's internal alarm circuitry may also send a discrete instruction signal 704 to an upstream or downstream power disconnect or transfer switch to interrupt or reroute the power flow. In this embodiment, the apparatus 701 may either derive its power from an internal energy storage device such as a battery, derive its power from the power line that the apparatus 701 is monitoring, or derive its power from some external third power source.

[0016] FIG. 8 shows a block diagram of the device 701 incorporated into the safety disconnect switch of a solar power system. Auxiliary input power is fed to an auxiliary power circuit 801 whose main purpose is to readjust the power to the proper level of a controller 802 and to monitor the health and status of the module, including temperature and input voltage levels. If the voltage falls outside of a predefined range or if the temperature becomes too high, the controller 802 sends a signal to a driver circuit 803 to open the main photovoltaic switch 804. The device 701 monitors the auxiliary input power, the photovoltaic input power, and the ambient environment. If it detects a sustained level disturbance or a pulse disturbance consistent with the characteristics of an EMP or solar wind, an alarm discrete indication signal is sent to the controller circuit 802 to force the driver circuit 803 to open the main switch and disconnect the photovoltaic power. An alternative embodiment has the device 701 send an alarm discrete indicator signal directly to the driver circuit 803 to trigger the opening of the main photovoltaic switch 804. In this embodiment, the device 701 may derive its own power either from a built-in energy storage device such as a battery, or from an auxiliary power input, a photovoltaic input, or some external third power source.

[0017] FIG. 9 shows an embodiment of a plug-in module that incorporates an embodiment. For purposes of protecting the internal electronics, the top 901 and bottom 902 of the housing may be layered with conductive shielding material to reduce radiated energy coupling into the circuitry. The circuitry is built on a printed circuit board assembly 903 and attached to the housing. An antenna 904 may be an on-board component or may be internally or externally mounted to the housings 901 and 902. An alternating current (AC) wall plug 905 is shown on the underside of the bottom housing 902. Similarly, an alternative embodiment may derive direct current (DC) power from a vehicle auxiliary receptacle rather than from an AC wall outlet.

[0018] FIG. 10 shows an embodiment of a battery-powered key fob module that houses an embodiment. For purposes of protecting the internal electronics, the top 1001 and bottom 1002 of the housing may be layered with conductive shielding material to reduce radiated energy coupling into the circuitry. The circuitry is built on a printed circuit board assembly 1003 and attached to the housing. An antenna 1005 may be an on-board component or may be internally or externally mounted to the housings 1001 and 1002. A battery or other energy storage device 1004 would also be included within the housing along with energy management hardware to maximize useful life.

[0019] FIG. 11 illustrates a plot showing the characteristics of a high-altitude nucleation electromagnetic pulse (EMP) waveform over time. EMP produces a complex transient disturbance with three distinct phases identified as E1, E2, and E3. The early-time E1 phase waveform has a rise time of about 3 ns and a pulse width of about 20 ns. The E1 phase waveform is followed by a mid-time waveform component of phase E2, which has a pulse width on the order of microseconds. Finally, the late-time waveform of phase E3 may last for a duration of seconds to hours. Similarly, waveforms resulting from the solar wind are comparable to EMP's E3, which has a duration lasting for seconds to hours.

[0020] As shown in FIG. 11, the nucleation EMP is described as including three distinct phases: an early time event E1, a middle time event E2, and a final time event E3. During E1, the electromagnetic disturbance is an extremely short, broadband pulse lasting from nanoseconds to hundreds of nanoseconds with amplitudes reaching tens of thousands of volts / meters, capable of destroying a wide range of electronic systems. During E2, the electromagnetic disturbance is comparable in duration to lightning lasting microseconds and has amplitudes exceeding 100 volts / meters, coupling most efficiently into media and long conductors. During E3, the electromagnetic disturbance is a sustained pulse lasting from seconds to hours that is lower in amplitude but can introduce harmful currents into very long conductors, such as the electromagnetic disturbances of the power grid. The solar wind can also lead to electromagnetic disturbances felt at the Earth's surface similar to the E3 component of EMP, lasting from seconds to hours, and coupling most efficiently into very long conductors.

[0021] The present invention is particularly useful in detecting solar wind or EMP. Both solar wind and EMP lead to potentially disruptive E3 electrical disturbances in infrastructure with long conductors, such as large-scale power distribution and communication systems. These persistent disturbances propagate along the conductors, affecting electronics that contain and are interconnected with the conductors in supervisory control and data acquisition (SCADA) systems, computers, transceivers, and other sensitive electronic hardware. The present invention monitors incoming power lines, particularly for persistent electrical disturbances indicative of EMP or solar wind, having durations in the range of seconds to hours.

[0022] EMP also produces powerful E1 and E2 electromagnetic pulse disturbances that propagate along conductors and through the atmosphere and couple directly into both large and small electronic assemblies, including but not limited to computers, microcontrollers, vehicles, wireless systems, home appliances, and cell phones. The present invention monitors incoming power lines and the surrounding environment for E1 and E2 electromagnetic pulse disturbances having durations in the nanosecond to microsecond range.

[0023] Figure 12 summarizes the waveform components resulting from an EMP. The E1 component has a nanosecond duration and can couple into both small and large electronics by radiative and conductive means. The E2 component has a microsecond duration and can couple into both small and large electronics by radiative and conductive means. The E3 component has a duration in the seconds to hours range and couples into large infrastructure such as power grids by induction and is then distributed to both large and small systems by conduction.

[0024] FIG. 13 shows how the persistent and pulse detection circuits are used to detect various waveform components associated with different phases of EMP or solar wind. The persistent disturbance detection circuit 1301 detects waveforms associated with the E3 phase of EMP as well as E3 waveforms resulting from solar wind or other long duration electrical disturbances. The pulse detection circuit 1302 detects transient electromagnetic pulse disturbances associated with the E1 and E2 phases. Once detected, visual indicators, audible indicators, and alarms providing discrete indicating signals are activated.

[0025] In summary, the present invention detects the complex time-varying conductive and radioactive disturbances associated with EMP or solar wind. The present invention not only provides visual and audible warnings, but also provides discrete indicating signals that may be used to cut off or redirect electrical flow. Detection of EMP or solar wind would provide early warning of a potentially destructive event, allowing protective action to be taken.

[0026] Examples of intended uses The present invention may be used to monitor voltage levels on power lines that power homes, businesses, military structures, trailers, recreational vehicles, boats, automobiles, or other motorized structures, systems, or devices. When the voltage level on the power line moves outside of an acceptable predetermined voltage level (i.e., normal operating range), the continuous level detection circuitry alerts the user with visual and audible alarms and discrete indicating signals that may be used to activate or trigger power disconnect circuitry. Additionally, the pulse detection circuitry monitors both the incoming power line and the surrounding environment for transient electromagnetic pulse disturbances associated with EMP or solar wind E1 and E2 phases.

[0027] The present invention is designed with numerous built-in protectors including shielding devices and transient surge protection devices to ensure device survival during EMP or solar wind disturbance events. Additionally, they are designed to operate at very high or low voltage levels to ensure the device continues to operate throughout the disturbance.

[0028] The present invention provides a unique and robust method of providing early warning of an EMP or solar wind, allowing users the opportunity to take appropriate protective action. Such actions may include opening main circuit breakers in their homes or businesses, unplugging critical or sensitive electrical devices, disconnecting antennas from radio systems, preparing to evacuate the area, or alerting others to the event. Additionally, embodiments may be incorporated into automatic power switching systems, such as automatic circuit breakers or transfer switches, to automatically disconnect or reroute power upon detecting an EMP or solar wind disturbance. Similarly, embodiments may be used to drive electromechanical actuators or mechanisms to physically initiate the disconnection of power (such as a main circuit breaker) in the event of a potentially harmful disturbance. Additionally, the embodiments may be incorporated into solar power system safety shutoff switches, providing another input condition under which the shutoff switch will shut off the power coming from the photovoltaic array. Finally, the other input condition may be added to a surge protection device (SPD) to provide a visual alarm, an audible alarm, or an indicator signal used to interrupt the flow of electricity.

[0029] Any letter designations such as (a) or (b) used to label a method claim step of any of a plurality of method claims are step headers applied for ease of reading and therefore should not be used to interpret the order or process order of the method steps recited in the claims. Any method claim that recites a particular order or process order will use those text words, rather than letter designations, to recite the particular order or process order.

[0030] Unless otherwise noted, terms such as "first" and "second" are used arbitrarily to distinguish between multiple elements that such terms describe, and as such, these terms are not necessarily intended to indicate a temporal or other priority of such elements.

[0031] Any trademarks listed herein are the property of their respective owners, and reference herein to such trademarks is generally intended to indicate the source of a particular product or service.

[0032] While the present invention has been described and illustrated in the above specification and drawings, it is understood that this description is by way of example only, and that numerous changes and modifications may be made by those skilled in the art without departing from the true spirit and scope of the invention. The examples in the accompanying drawings depict only exemplary constructions and embodiments, although alternative embodiments are available given the teachings of this patent disclosure.

Claims

1. 1. An apparatus for detecting transient electromagnetic pulse disturbances associated with at least one of an E1 phase and an E2 phase of an electromagnetic pulse, the apparatus comprising: an electromagnetic pulse sensitive feed for receiving a received signal, said electromagnetic pulse sensitive feed including a power line, said power line being an AC mains power line; a pulse detector operatively coupled to the electromagnetic pulse sensitive feed to detect pulse disturbance durations of at least one of microseconds and nanoseconds and to output a detected pulse indicative signal, the pulse detector including an activation circuit to convert the detected pulse indicative signal into an alarm signal; an alarm operably coupled to the activation circuit for an indication regarding the alarm signal; the device including the pulse detector and activation circuitry is contained within a housing and further includes at least a pair of AC mains wall plug lugs extending from a side of the housing and operably coupled to the AC mains power line; Device.

2. The apparatus of claim 1 , wherein the electromagnetic pulse sensitive feed includes at least one of an antenna feed and the power line.

3. 10. The apparatus of claim 1, wherein the pulse detector is operatively coupled to the electromagnetic pulse sensitive feed to perform at least one of edge, pulse, and impulse detection of the received signal and to output a pulse indicative signal being detected.

4. 10. The apparatus of claim 1, wherein the pulse detector is selected from the group consisting of a monostable multivibrator, a peak detection device, a high speed sampler, a flip-flop, a high gain comparator, and an extremely fast turn-on time transient protection device.

5. The apparatus of claim 1 , wherein the activation circuitry includes a latch coupled to the alarm.

6. 10. The apparatus of claim 1, wherein the alarm comprises an indicator selected from the group consisting of a visual indicator, an audible indicator, and a discrete indicative signal.

7. a sustained level detection circuit for detecting transient electromagnetic pulse disturbances associated with an E3 phase of at least one of an electromagnetic pulse and solar wind on the power line, the sustained level detection circuit comprising: a low pass filter operably coupled to the power supply line; a discriminator circuit operatively coupled to the low pass filter for transmitting a signal indicating that the output of the low pass filter exceeds an overvoltage level; 10. The apparatus of claim 1, further comprising a sustained level detection circuit comprising:

8. the device is constructed to ensure survivability of the device during an electromagnetic pulse and solar wind; said electromagnetic pulse sensitive feed being constructed from discrete analog components; The apparatus of claim 1 , wherein the pulse detector is constructed from discrete analog components.

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