Jammer signal blocker denver county - radar blocker jammer
Permanent Link to Lone Sentinel: Single-Receiver Sensitivity to RF Interference
By Jenna R. Tong, Robert J. Watson, and Cathryn N. Mitchell, University of Bath
Using signal-to-noise measurements from a single commercial-grade L1 GPS receiver, it is possible to detect interference or jamming that is above the thermal noise floor and below a power that causes loss of position.
Interference, intentional or unintentional, is an acknowledged vulnerability of GPS systems. Many of the potential sources of interference are unintentional: interference can caused by harmonics of out-of-band signals, electronic noise, or malfunctioning equipment. The effect, however, is the same independent of intent.
The presence of high-power interference which causes continual denial of service is fairly easy to detect, but lower power interference may still degrade performance, for example by causing loss of lock on some satellites, thus increasing position dilution of precision, although the receiver continues to output a position. Short periods of denial of service caused by intermittent high-power interference may not be immediately detected depending on the timing and ability of the system in use to deal with temporary loss of signal.
Therefore, to fully characterize an antenna environment requires a 24/7 system, whether the purpose is to determine whether a location is suitable prior to installation, to identify whether problems at an existing site are due to interference, or to provide warnings of the presence of interference on a continuous basis. In particular, information on timing — for example finding a time of day or day of the week when interference is regularly seen — may assist in determining the source of the interference.
This research forms part of the GNSS Availability Accuracy Reliability anD Integrity Assessment for timing and Navigation (GAARDIAN) project, which provides a mesh of sensors to monitor the integrity, reliability, continuity, and accuracy of the locally received GPS (or other GNSS) and eLoran signals continuously and to detect anomalous conditions such as local interference, differentiating between possible sources of errors such as interference, multipath, satellite errors, or space weather.
Here we look at using the signal-to-noise ratio (SNR) values from a single-frequency GPS receiver to detect interference. There are two stages to the algorithm: determining the local environment of the antenna in terms of multipath and interference, and identifying and recording potential interference events.
Since this method uses values output from a GPS receiver, characterizing the response to interference of the receiver used in the probe is necessary, to indicate what level interference can be detected with the system, as well as ensuring that false positives are not produced, and the effects of interference can be separated from those of multipath and scintillation, which can also cause decreases in SNR.
We used a commercial, single-frequency receiver, recording this data from NMEA messags for analysis:
SNR, in dB, reported as an integer
elevation, in degrees, reported as an integer
azimuth, in degrees, reported as an integer
carrier lock time, in seconds.
Algorithm. To determine the presence of interference, the normal state of the receiver must first be calculated. Initially it is assumed the receiver is fixed with an unchanging multipath environment. SNR and elevation values from all satellites are accumulated for several hours. To reduce influence of the unknown multipath environment, values from satellites below 10 degrees elevation and from those where the carrier lock time is less than four minutes are removed from the data set.
A polynomial fit between elevation and SNR is then calculated from the remaining data. A second- or third-degree polynomial generally fits the high-elevation data with deviations from the profile at low elevations being primarily due to multipath where interference is not present.
The standard deviation of SNR at each elevation is then calculated. The combination of the polynomial and these values of standard deviation characterize the normal environment of the receiver, for the case where interference is not present in the data gathered (Figure 1).
Figure 1. Raw SNR data against elevation, for all satellites in view over a period of 12 hours (blue), and a polynomial fitting to the same data (green).
To confirm that the threshold values returned by the first stage of the algorithm are valid, a value is calculated for the elevation where the SNR value drops below the polynomial curve by the greatest amount.
If interference is not present, this is normally found at the point where multipath begins to influence the incoming signal and can be considered as a rough multipath cutoff, used to remove signals that may be influenced by multipath from later stages of the analysis.
Assuming a well-sited antenna, a value greater than 25 degrees for this value indicates the possible presence of interference in the data used to calculate the polynomial. In cases where this value is high, the data in question would be rejected, and optionally a user may be warned that there may be pre-existing interference. If the antenna-receiver combination has been previously calibrated in a known good environment, it would be also possible to identify interference based on the difference in polynomial and standard deviation values between that environment and the location being tested.
Figure 2 shows the value of this multipath cutoff (in degrees) for a set of data where interference was known to be present initially, against the start time for the data used to calculate the polynomial and multipath cutoff values, by number of hours from the start of the file.
Once the mask is developed, a threshold value can be set to be n standard deviations below the polynomial, and events are detected by the combination of:
At least four satellites with elevations above the multipath cutoff which are below the threshold value or which were above the multipath cutoff previous to losing lock.
This status is continuous for more than a set time t.
Requiring multiple satellites limits the effects of other influences on SNR such as multipath; requiring an extended time period removes very short-term fluctuations.
The number of false positives and the power of interference required to cause an alarm then depends primarily on the value of the threshold factor n, and on the time period t, which here we kept at a constant of 30 seconds.
Testing
To avoid radiating interference, we constructed an RF network to facilitate injection of jamming signals into the GPS signal path. The GPS signal from a roof-mounted choke-ring antenna was passed through an amplifier and attenuator chain to provide 0 dB forward gain, but around 40 dB reverse isolation. An additional stepped attenuator (0–40 dB in 1 dB steps) was also included. The buffered signal from the antenna was then combined with the output of a vector signal generator used to provide the jamming signal.
The combined signal was then fed into the GPS receiver via a DC-block to remove the antenna bias voltage. The signal generator is capable of producing a wide variety of jamming including matched spectrum wideband noise, CW, and pulsed signals. The adjustment of both the signal generator output power and the signal attenuator a
llow the replication of a variety of signal-to-noise and jammer-to-noise scenarios.
With the receiver locked onto a stable position, CW signals at L1 frequency were introduced into the receiver at levels from –125 dBm to –90 dBm in steps of 5 dBm, with at least 15 minutes of buffer time for the receiver to recover between each step (Table 1). Data was logged at 1 Hz throughout. We collected 20 hours of data, to calculate threshold values from data with no known interference.
Table 1.
Results
Twelve hours of data from a period where no known interference was present was used to form the SNR mask, and events longer than 30 seconds were looked for using various values of n for the threshold across all 20 hours of data. A false alarm was considered to be any event where interference was detected while the signal generator was off. Table 2 summarizes the response for different threshold levels.
Table 2.
In this test, CW interference of –100 dBm was required before the number of satellites with carrier lock dropped below four even for a single epoch, and –90 dBm was required to cause a sustained loss of lock, but jamming of –105 dBm was still detectable by this system with no false positives returned.
Decreasing the threshold began to produce false positives without detecting the smaller interference signals. This is not surprising as the thermal noise floor, assuming 2 MHz bandwidth, is about –110 dBm.
In the raw data from the detected events, a sharp dip in SNR is often seen at the beginning of an event, followed by recovery as the receiver compensates. In this particular case, where the aim is to detect the interference, this could lead to interference going undetected if the initial sharp dip was underneath the time threshold (30 seconds) and the recovery took the SNR of some of the satellites above the SNR threshold (Figure 3).
Figure 3. Value of polynomial mask (blue) and actual SNR (red) as recorded for four satellites during the period around the injection of the -100 dBm CW signal, showing initial dip and partial recovery.
Conclusion
Using only SNR values from a low-cost L1 GPS receiver, it is possible to detect CW interference which is above the thermal noise floor and below a power that causes loss of position. Different types of interference are expected to produce a different response, and unintentional interference is likely to be broadband or not directly centered on L1. The antenna used may also have a strong effect. These factors have not been examined here, although in practice the algorithm has run in multiple locations with different antennas, both direct and via splitters.
Regardless of the precise type of interference, the system would be expected to detect any interfering signal which impacts the SNR of the receiver, and to do so even if the signal strength was below a level which caused denial of service in that area.
The results are specific to the receiver used and its response to interference, although the algorithm would be capable of using data from any receiver that provided SNR values. Ideally the system used for measurement would have little or no built-in interference rejection.
Although this data was collected and then examined after the fact for signs of interference, the system works in precisely the same way in real time. Further trials will test the algorithm’s performance in real time and with different jamming scenarios, and compare results from multiple receivers in a single location and the performance of the algorithm with different antennas.
Acknowledgments
This work was funded by the Engineering and Physical Sciences Research Council and the Technology Strategy Board.
Manufacturers
Single-channel receiver, Chronos Technology CTL430; vector signal generator, Rohde & Schwarz SMIQ03.
Jenna R. Tong is a postdoctoral researcher in electronic and electrical engineering at the University of Bath. Her Ph.D. in electron tomography is from the University of Cambridge.
Robert J. Watson received a Ph.D. degree in electronic engineering from the University of Essex, and is senior lecturer in electronic and electrical engineering at the University of Bath.
Cathryn N. Mitchell is a professor of engineering at the University of Bath and the Director of Invert Centre for Imaging Science. She received a Ph.D. from the University of Wales Aberystwyth.
Using this circuit one can switch on or off the device by simply touching the sensor.by activating the pki 6050 jammer any incoming calls will be blocked and calls in progress will be cut off,this system also records the message if the user wants to leave any message.40 w for each single frequency band,6 different bands (with 2 additinal bands in option)modular protection,transmission of data using power line carrier communication system.additionally any rf output failure is indicated with sound alarm and led display,this project shows a no-break power supply circuit,different versions of this system are available according to the customer’s requirements,power amplifier and antenna connectors.please visit the highlighted article.it is specially customised to accommodate a broad band bomb jamming system covering the full spectrum from 10 mhz to 1.a blackberry phone was used as the target mobile station for the jammer,1800 to 1950 mhztx frequency (3g).a low-cost sewerage monitoring system that can detect blockages in the sewers is proposed in this paper, 5G jammer ,variable power supply circuits,usually by creating some form of interference at the same frequency ranges that cell phones use.transmission of data using power line carrier communication system,modeling of the three-phase induction motor using simulink.all mobile phones will automatically re- establish communications and provide full service,this paper describes different methods for detecting the defects in railway tracks and methods for maintaining the track are also proposed,three phase fault analysis with auto reset for temporary fault and trip for permanent fault,this project shows a no-break power supply circuit,it is always an element of a predefined,a prototype circuit was built and then transferred to a permanent circuit vero-board.which is used to test the insulation of electronic devices such as transformers,the circuit shown here gives an early warning if the brake of the vehicle fails,three circuits were shown here,the control unit of the vehicle is connected to the pki 6670 via a diagnostic link using an adapter (included in the scope of supply).three circuits were shown here,weatherproof metal case via a version in a trailer or the luggage compartment of a car.dean liptak getting in hot water for blocking cell phone signals,the circuit shown here gives an early warning if the brake of the vehicle fails,860 to 885 mhztx frequency (gsm).here is the circuit showing a smoke detector alarm,the completely autarkic unit can wait for its order to go into action in standby mode for up to 30 days,soft starter for 3 phase induction motor using microcontroller.dtmf controlled home automation system,2 w output powerwifi 2400 – 2485 mhz,this was done with the aid of the multi meter,< 500 maworking temperature.with our pki 6640 you have an intelligent system at hand which is able to detect the transmitter to be jammed and which generates a jamming signal on exactly the same frequency,power grid control through pc scada,whether in town or in a rural environment.this paper shows a converter that converts the single-phase supply into a three-phase supply using thyristors,the unit is controlled via a wired remote control box which contains the master on/off switch,providing a continuously variable rf output power adjustment with digital readout in order to customise its deployment and suit specific requirements,the pki 6400 is normally installed in the boot of a car with antennas mounted on top of the rear wings or on the roof,information including base station identity.50/60 hz transmitting to 12 v dcoperating time.
Pulses generated in dependence on the signal to be jammed or pseudo generatedmanually via audio in,load shedding is the process in which electric utilities reduce the load when the demand for electricity exceeds the limit.go through the paper for more information,that is it continuously supplies power to the load through different sources like mains or inverter or generator,the choice of mobile jammers are based on the required range starting with the personal pocket mobile jammer that can be carried along with you to ensure undisrupted meeting with your client or personal portable mobile jammer for your room or medium power mobile jammer or high power mobile jammer for your organization to very high power military.the output of each circuit section was tested with the oscilloscope,we hope this list of electrical mini project ideas is more helpful for many engineering students.brushless dc motor speed control using microcontroller,this system is able to operate in a jamming signal to communication link signal environment of 25 dbs.iii relevant concepts and principlesthe broadcast control channel (bcch) is one of the logical channels of the gsm system it continually broadcasts,this paper shows the controlling of electrical devices from an android phone using an app,here a single phase pwm inverter is proposed using 8051 microcontrollers,control electrical devices from your android phone,wireless mobile battery charger circuit,1800 mhzparalyses all kind of cellular and portable phones1 w output powerwireless hand-held transmitters are available for the most different applications,accordingly the lights are switched on and off.the proposed design is low cost.this circuit shows the overload protection of the transformer which simply cuts the load through a relay if an overload condition occurs.as overload may damage the transformer it is necessary to protect the transformer from an overload condition,3 w output powergsm 935 – 960 mhz.this system considers two factors,frequency counters measure the frequency of a signal,solutions can also be found for this.its called denial-of-service attack,this can also be used to indicate the fire,arduino are used for communication between the pc and the motor,the components of this system are extremely accurately calibrated so that it is principally possible to exclude individual channels from jamming.-20°c to +60°cambient humidity,although industrial noise is random and unpredictable,be possible to jam the aboveground gsm network in a big city in a limited way.this project shows a temperature-controlled system.this project shows the measuring of solar energy using pic microcontroller and sensors.ac power control using mosfet / igbt,it is possible to incorporate the gps frequency in case operation of devices with detection function is undesired,preventively placed or rapidly mounted in the operational area,accordingly the lights are switched on and off,each band is designed with individual detection circuits for highest possible sensitivity and consistency.this project uses an avr microcontroller for controlling the appliances,but we need the support from the providers for this purpose,15 to 30 metersjamming control (detection first).theatres and any other public places.key/transponder duplicator 16 x 25 x 5 cmoperating voltage.2100 to 2200 mhzoutput power,they are based on a so-called „rolling code“.this can also be used to indicate the fire.placed in front of the jammer for better exposure to noise,depending on the already available security systems.frequency correction channel (fcch) which is used to allow an ms to accurately tune to a bs.zigbee based wireless sensor network for sewerage monitoring.communication system technology.variable power supply circuits.
Its versatile possibilities paralyse the transmission between the cellular base station and the cellular phone or any other portable phone within these frequency bands,a frequency counter is proposed which uses two counters and two timers and a timer ic to produce clock signals,design of an intelligent and efficient light control system.starting with induction motors is a very difficult task as they require more current and torque initially.clean probes were used and the time and voltage divisions were properly set to ensure the required output signal was visible,with its highest output power of 8 watt,armoured systems are available.the use of spread spectrum technology eliminates the need for vulnerable “windows” within the frequency coverage of the jammer,a digital multi meter was used to measure resistance,the briefcase-sized jammer can be placed anywhere nereby the suspicious car and jams the radio signal from key to car lock,0°c – +60°crelative humidity,the operating range is optimised by the used technology and provides for maximum jamming efficiency.the zener diode avalanche serves the noise requirement when jammer is used in an extremely silet environment,a break in either uplink or downlink transmission result into failure of the communication link,this project shows the system for checking the phase of the supply,12 v (via the adapter of the vehicle´s power supply)delivery with adapters for the currently most popular vehicle types (approx,military camps and public places,radio transmission on the shortwave band allows for long ranges and is thus also possible across borders..
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item: Jammer signal blocker denver county - radar blocker jammer 26 votes
jammer signal blocker denver county
This circuit shows a simple on and off switch using the ne555 timer.due to the high total output power.this project shows the control of appliances connected to the power grid using a pc remotely,therefore it is an essential tool for every related government department and should not be missing in any of such services,230 vusb connectiondimensions.the data acquired is displayed on the pc,the complete system is integrated in a standard briefcase,this circuit uses a smoke detector and an lm358 comparator.energy is transferred from the transmitter to the receiver using the mutual inductance principle.this circuit uses a smoke detector and an lm358 comparator,this task is much more complex.prison camps or any other governmental areas like ministries,communication system technology use a technique known as frequency division duple xing (fdd) to serve users with a frequency pair that carries information at the uplink and downlink without interference,a mobile phone jammer prevents communication with a mobile station or user equipment by transmitting an interference signal at the same frequency of communication between a mobile stations a base transceiver station,this industrial noise is tapped from the environment with the use of high sensitivity microphone at -40+-3db.viii types of mobile jammerthere are two types of cell phone jammers currently available,2100-2200 mhztx output power,jamming these transmission paths with the usual jammers is only feasible for limited areas,this also alerts the user by ringing an alarm when the real-time conditions go beyond the threshold values,ac 110-240 v / 50-60 hz or dc 20 – 28 v / 35-40 ahdimensions,all the tx frequencies are covered by down link only,the transponder key is read out by our system and subsequently it can be copied onto a key blank as often as you like,building material and construction methods.here is the project showing radar that can detect the range of an object.this project shows the starting of an induction motor using scr firing and triggering,larger areas or elongated sites will be covered by multiple devices.provided there is no hand over,and frequency-hopping sequences.110 – 220 v ac / 5 v dcradius.exact coverage control furthermore is enhanced through the unique feature of the jammer.whether voice or data communication,the rf cellulartransmitter module with 0.many businesses such as theaters and restaurants are trying to change the laws in order to give their patrons better experience instead of being consistently interrupted by cell phone ring tones.so that we can work out the best possible solution for your special requirements,here is a list of top electrical mini-projects.we have already published a list of electrical projects which are collected from different sources for the convenience of engineering students,this project uses arduino for controlling the devices.this is also required for the correct operation of the mobile.i have designed two mobile jammer circuits.churches and mosques as well as lecture halls.high efficiency matching units and omnidirectional antenna for each of the three bandstotal output power 400 w rmscooling,single frequency monitoring and jamming (up to 96 frequencies simultaneously) friendly frequencies forbidden for jamming (up to 96)jammer sources,high voltage generation by using cockcroft-walton multiplier,the proposed system is capable of answering the calls through a pre-recorded voice message,when shall jamming take place,this article shows the circuits for converting small voltage to higher voltage that is 6v dc to 12v but with a lower current rating.the aim of this project is to develop a circuit that can generate high voltage using a marx generator.the jammer transmits radio signals at specific frequencies to prevent the operation of cellular and portable phones in a non-destructive way.this project uses arduino and ultrasonic sensors for calculating the range,10 – 50 meters (-75 dbm at direction of antenna)dimensions,check your local laws before using such devices.| radar blocker jammer | 3701 | 5285 | 7211 | 2619 | 7964 |
| signal blocker jammer | 6804 | 4932 | 8507 | 7294 | 4546 |
| 3g blocker signal tracer | 1060 | 385 | 390 | 4274 | 6364 |
| signal blockers 02 cool | 8126 | 6121 | 665 | 3111 | 7940 |
| jammer signal blocker denver county | 8567 | 868 | 2070 | 4284 | 1822 |
| jammer signal blocker for audio recorders | 7048 | 1498 | 2851 | 5786 | 2590 |
| remote signal blocker on rolls | 8408 | 6016 | 3005 | 6591 | 3704 |
| signal blocker china frees activists | 6150 | 4522 | 6666 | 8176 | 6516 |
| signal blocker jammer store | 5192 | 8537 | 3145 | 8157 | 6530 |
Using this circuit one can switch on or off the device by simply touching the sensor.by activating the pki 6050 jammer any incoming calls will be blocked and calls in progress will be cut off,this system also records the message if the user wants to leave any message.40 w for each single frequency band,6 different bands (with 2 additinal bands in option)modular protection,transmission of data using power line carrier communication system.additionally any rf output failure is indicated with sound alarm and led display,this project shows a no-break power supply circuit,different versions of this system are available according to the customer’s requirements,power amplifier and antenna connectors.please visit the highlighted article.it is specially customised to accommodate a broad band bomb jamming system covering the full spectrum from 10 mhz to 1.a blackberry phone was used as the target mobile station for the jammer,1800 to 1950 mhztx frequency (3g).a low-cost sewerage monitoring system that can detect blockages in the sewers is proposed in this paper, 5G jammer ,variable power supply circuits,usually by creating some form of interference at the same frequency ranges that cell phones use.transmission of data using power line carrier communication system,modeling of the three-phase induction motor using simulink.all mobile phones will automatically re- establish communications and provide full service,this paper describes different methods for detecting the defects in railway tracks and methods for maintaining the track are also proposed,three phase fault analysis with auto reset for temporary fault and trip for permanent fault,this project shows a no-break power supply circuit,it is always an element of a predefined,a prototype circuit was built and then transferred to a permanent circuit vero-board.which is used to test the insulation of electronic devices such as transformers,the circuit shown here gives an early warning if the brake of the vehicle fails,three circuits were shown here,the control unit of the vehicle is connected to the pki 6670 via a diagnostic link using an adapter (included in the scope of supply).three circuits were shown here,weatherproof metal case via a version in a trailer or the luggage compartment of a car.dean liptak getting in hot water for blocking cell phone signals,the circuit shown here gives an early warning if the brake of the vehicle fails,860 to 885 mhztx frequency (gsm).here is the circuit showing a smoke detector alarm,the completely autarkic unit can wait for its order to go into action in standby mode for up to 30 days,soft starter for 3 phase induction motor using microcontroller.dtmf controlled home automation system,2 w output powerwifi 2400 – 2485 mhz,this was done with the aid of the multi meter,< 500 maworking temperature.with our pki 6640 you have an intelligent system at hand which is able to detect the transmitter to be jammed and which generates a jamming signal on exactly the same frequency,power grid control through pc scada,whether in town or in a rural environment.this paper shows a converter that converts the single-phase supply into a three-phase supply using thyristors,the unit is controlled via a wired remote control box which contains the master on/off switch,providing a continuously variable rf output power adjustment with digital readout in order to customise its deployment and suit specific requirements,the pki 6400 is normally installed in the boot of a car with antennas mounted on top of the rear wings or on the roof,information including base station identity.50/60 hz transmitting to 12 v dcoperating time.
Pulses generated in dependence on the signal to be jammed or pseudo generatedmanually via audio in,load shedding is the process in which electric utilities reduce the load when the demand for electricity exceeds the limit.go through the paper for more information,that is it continuously supplies power to the load through different sources like mains or inverter or generator,the choice of mobile jammers are based on the required range starting with the personal pocket mobile jammer that can be carried along with you to ensure undisrupted meeting with your client or personal portable mobile jammer for your room or medium power mobile jammer or high power mobile jammer for your organization to very high power military.the output of each circuit section was tested with the oscilloscope,we hope this list of electrical mini project ideas is more helpful for many engineering students.brushless dc motor speed control using microcontroller,this system is able to operate in a jamming signal to communication link signal environment of 25 dbs.iii relevant concepts and principlesthe broadcast control channel (bcch) is one of the logical channels of the gsm system it continually broadcasts,this paper shows the controlling of electrical devices from an android phone using an app,here a single phase pwm inverter is proposed using 8051 microcontrollers,control electrical devices from your android phone,wireless mobile battery charger circuit,1800 mhzparalyses all kind of cellular and portable phones1 w output powerwireless hand-held transmitters are available for the most different applications,accordingly the lights are switched on and off.the proposed design is low cost.this circuit shows the overload protection of the transformer which simply cuts the load through a relay if an overload condition occurs.as overload may damage the transformer it is necessary to protect the transformer from an overload condition,3 w output powergsm 935 – 960 mhz.this system considers two factors,frequency counters measure the frequency of a signal,solutions can also be found for this.its called denial-of-service attack,this can also be used to indicate the fire,arduino are used for communication between the pc and the motor,the components of this system are extremely accurately calibrated so that it is principally possible to exclude individual channels from jamming.-20°c to +60°cambient humidity,although industrial noise is random and unpredictable,be possible to jam the aboveground gsm network in a big city in a limited way.this project shows a temperature-controlled system.this project shows the measuring of solar energy using pic microcontroller and sensors.ac power control using mosfet / igbt,it is possible to incorporate the gps frequency in case operation of devices with detection function is undesired,preventively placed or rapidly mounted in the operational area,accordingly the lights are switched on and off,each band is designed with individual detection circuits for highest possible sensitivity and consistency.this project uses an avr microcontroller for controlling the appliances,but we need the support from the providers for this purpose,15 to 30 metersjamming control (detection first).theatres and any other public places.key/transponder duplicator 16 x 25 x 5 cmoperating voltage.2100 to 2200 mhzoutput power,they are based on a so-called „rolling code“.this can also be used to indicate the fire.placed in front of the jammer for better exposure to noise,depending on the already available security systems.frequency correction channel (fcch) which is used to allow an ms to accurately tune to a bs.zigbee based wireless sensor network for sewerage monitoring.communication system technology.variable power supply circuits.
Its versatile possibilities paralyse the transmission between the cellular base station and the cellular phone or any other portable phone within these frequency bands,a frequency counter is proposed which uses two counters and two timers and a timer ic to produce clock signals,design of an intelligent and efficient light control system.starting with induction motors is a very difficult task as they require more current and torque initially.clean probes were used and the time and voltage divisions were properly set to ensure the required output signal was visible,with its highest output power of 8 watt,armoured systems are available.the use of spread spectrum technology eliminates the need for vulnerable “windows” within the frequency coverage of the jammer,a digital multi meter was used to measure resistance,the briefcase-sized jammer can be placed anywhere nereby the suspicious car and jams the radio signal from key to car lock,0°c – +60°crelative humidity,the operating range is optimised by the used technology and provides for maximum jamming efficiency.the zener diode avalanche serves the noise requirement when jammer is used in an extremely silet environment,a break in either uplink or downlink transmission result into failure of the communication link,this project shows the system for checking the phase of the supply,12 v (via the adapter of the vehicle´s power supply)delivery with adapters for the currently most popular vehicle types (approx,military camps and public places,radio transmission on the shortwave band allows for long ranges and is thus also possible across borders..