Introduction:-The Duration of the Project (4th January 2011 to 15 February 2011).The Location of the Project was (Kapurthala)I had worked as an engineer in this project.Background.This Project was carried out during my studies of B.
Tech at my college. This project was taken by the three members and H.O.D. of our department. This basic background of choosing such project was to enhance the technical knowledge as well as application of such technical knowledge to enhance our practical hand on experience of Basic electronics concepts.
My College comes under I.K. Gujral Punjab Technical university (Now) Punjab technical university (Then) in 2011. This project was immediately taken by our team members after completing 6 Months training. Objective of this Project:- The Objective of this project is oriented around to develop a mobile phone detector, As Mobile Phone detector can help us overcome many problems of Unauthorized uses of Mobile phones like during exams or in hospitals.
In this project there was detection of Electromagnetic waves /Radiations in their respective frequency bands and then detection of same. There will be detection of RF Signal which further gives an alarm and then it results into the cease of mobile phone signal. There are lots of future scopes of this project. Using of mobile phones for spying and unauthorized use of it can be eliminated. Responsibilities: My responsibility in this project was to study the resources need to be creating and its technical specification in details, Such as developing the circuit diagram, assembly of items into the PCB and then arranging the required components of specifications..1. Making the basic approach of the project.
2. Creating the circuit diagram3. Selecting the components that would be needed according to the specifications4. Arranging the components on PCB5. Components include resistors, capacitors, LED. 6. Training my fellow team members in order to complete the project.
7. Making the Project report and then submit it into the department.8. Presenting the Project to the Dean and chairman of the college.9.
Defining the future uses of the project.Organization Chart: – The organization chart of the project was as follows.Personal Engineering Activities:- After Conceiving the idea of the project about making a phone detector, I first started to learn about the RF Signals transmit by the mobile phones through different frequency bands. After studying about it the it’s detection range has been decided. After it I had come across list of components required according to the project along with the circuit diagram of same, I thought about two circuit diagrams; one circuit is for when cell phone has not been detected and other one for when mobile phone has been detected. 1. Hardware descriptions are as follows about the project.1.
LED’s ( used for indication whether the mobile phone is detected or not)2. Buzzer ( Used for warning as a mobile phone has been detected)3. Resistors are used 4 typesa. 2×100 K? Resistorsb.
2×2.2M? Resistorsc. 2x1K? Resistorsd. 15K? Resistor4. Capacitors are used 6 Typesa. 2x22pF Capacitorsb. 2×01µF Capacitorsc. 0.
22µF Capacitord. 100µF Capacitore. 0.01µF Capacitorf. 4.7 µF Capacitorg. 47µF Capacitor5.
2x LED’s6. IC CA313057. Antenna8. Power supply9.
ICNE555 (Timer)10. T1 BC548 (Transistor)11. On/Off Switch12.
PCB.While using the concepts of Network analysis and Synthesis, I had developed a circuit, which first detects the signal of any mobile phone in unauthorized space. There follows the Circuit diagram. The Process has been bifurcated in to two parts When the signal is detected, and the other parts is buzzer starts buzzing after detecting the sound.Here is the description of circuit diagram,First half circuit describes about the Antenna has been connected to Capacitor of 22pF serially then 0.22 µF Capacitor has been placed parallaly to it. It has two electrodes which is separated by dielectric.
The reason behind using a 0.22 µF capacitor because of its low value as well as its capacity to detect the mobile radiations. And the Capacitor is used as a small loop aerial and works like a coil which discharge current and to ability to oscillate, and then an normal RF Signals can be detected by the capacitor.
The other part used is OP Amp with MOSFET inputs as well as Bipolar output. MOSFET Transistors are used to provide very high impedance and lower current value of 10pA. It is very efficient for low input current P Channel MOSFET are Gate protected for input of very high impedance Its voltage capability come down to 0.5 V below the negative supply terminal, On the other hand at Output circuit CMOS Transistor-pair which is capable of changing the output voltage to 10mV is used. After OPAMP’s a IC NE555 Timer is connected as in circuit, It is there to produce the accurate timing pulses, and its time delay completely controlled by the external resistor and capacitor, and its duty cycle is controlled by two eternal resistor and one capacitor.
A Sound generator is connected further to it its time delays has been adjusted by capacitors used along IC NE555 timer which is wired as monostable multi vibrator.Working of Mobile phone detector.As, you know the operation of whole device has been divided into two parts, the first part starts with a Detection of signal, The Capacitor of capacity 0.
22 µF will detect the signals of high frequency because the one side of capacitor gets direct current from the positive rail, and capacitor gets its energy for storage and then redistribute the energy to inputs of IC with the 1.4 Volts. With output remaining zero. CA3130 OPAMP worked as an inverting amplifier showing high gain and thus results to provide the high speed performance to amplify the signals detected by Capacitor C7, As two resistors R6 and R7 are biased with one capacitor C7 from One terminal. Capacitor 100µF (C6) will prevent any fluctuations in the bias voltage, After detecting the high frequency signals the Capacitor c& will get the energized and upset the balanced state of OPAMP. This will trigger the Transistor which is wired as a switch continues to give signals to LED D1 for operation.
LED will start flashing and Beeping of Buzzer will starts The time pulses can be adjusted by the capacitor attached to it.