* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download telephone-intrusion-notification-system
Regenerative circuit wikipedia , lookup
Schmitt trigger wikipedia , lookup
Radio transmitter design wikipedia , lookup
Transistor–transistor logic wikipedia , lookup
Resistive opto-isolator wikipedia , lookup
Power electronics wikipedia , lookup
Valve RF amplifier wikipedia , lookup
Trionic T5.5 wikipedia , lookup
Telecommunications engineering wikipedia , lookup
Telephone newspaper wikipedia , lookup
Iwatsu Electric wikipedia , lookup
Immunity-aware programming wikipedia , lookup
Charlieplexing wikipedia , lookup
Telecommunications relay service wikipedia , lookup
Crossbar switch wikipedia , lookup
Switched-mode power supply wikipedia , lookup
Telephone exchange wikipedia , lookup
History of telecommunication wikipedia , lookup
1 Telephone Intrusion Notification System Lekshmi. III SEM EC, LBS College of Engineering, Trivandrum Power supply D1 IN 4007 1 P 7812 230 V AC 3 2 100 R N 12-0-12 V D2 IN 4007 500 mA Transformer + C1 2200 uF 25 V Power ON 12 V DC LED Yellow Powe Supply 12 Volt 500 mA Common Ground Power supply to the circuit is derived from a 12-0-12 500 mA step-down transformer. The low voltage AC is rectified by IN 4007 diodes and made Ripple free by 2200 uF capacitor. IC 7812 is used to give 12 volt regulated power to the circuit. Light Sensor LDR (Light Dependent Resistor) is used as the light sensor for the automatic operation of the circuit at sunset. LDR has low resistance about 100 ohms when it is illuminated by the day light and it remains conducting. The resistance of LDR increases to 1 Meg ohm or more in darkness and becomes non conducting. LDR is used to give a high voltage at the reset pin 12 of IC1 (CD 4060) to prevent its oscillation. IC1 oscillates only when its pin 12 becomes low at sunset as the LDR cease conducting. This enables the IC1. In the morning, when light falls on the LDR it conducts and disables IC1. Preset VR1 adjusts the sensitivity of LDR to the particular light level. 2 Long duration Timer CD 4060(IC1) is used as a long duration timer to activate the remaining part of the circuit after 4 hours around 10 pm. The timer circuit is designed using the 14 stage ripple counter IC CD 4060 to give 4 hours timing by taking pin 2 as output. When the reset pin12 of IC1 becomes low at sunset, it starts oscillation. Resistor R3 along with VR2 and capacitor C1 maintains the oscillation of IC1 as indicated by the blinking of LED 1(Green LED) connected to its output pin 7(Q3).The timeout period of the timer can be calculated using the formula t = 2 n / f osc = in seconds. ‘n’ is the selected Q output f osc = 1 / 2.5 (R1.C1) R1 is the resistor in ohms connected to the pin 10 and C1 is the capacitor in farads connected to the pin 9 of IC1. When the pin 2 becomes high diode IN 4148 forward biases and inhibits further oscillation of IC1 and pin 2 output remains high till IC1 resets in the morning. When the output pin2 of IC1 becomes high, Transistor T1 (BC 547) conducts and provides power to IC2 (CD 4060) and reed switch. Reed switch is used as a door switch to activate the circuit when the door is opened. It is a normally open type (NO) so that it opens when there is no magnet is placed close to it. In the arrangement, a magnet is fixed to the door and the reed switch to the frame. So when the door is closed, magnet will pull the contacts of the reed switch so as to make it conducting. Reset pin 12 of IC2 gets a high voltage through the reed switch and IC2 remains standby. CD 4060 (IC2) is used as a short duration timer with 1 minute ON/OFF cycles by taking pin 13 output. Capacitor C2 and resistor R8 gives the one minute time cycled from output pin 13. When the door is opened, reed switch and magnet separates and the contacts of reed switch opens. At this time, pin12 of IC2 goes low and it starts oscillating. After one minutes its pin 13 becomes high to trigger relay driving transistors T2, and T3. Two relays are used to control the telephone and tape recorder. Relay 1 is DPDT (Double Pole Double Throw) is used to connect the off hook switch and redial switch of telephone. When Relay 1 energize, its NC contacts breaks so that the phone will be in the OFF Hook state. At the same time its NO contacts connects the redial switch. In short, relay 1 makes the telephone similar to a person taking the receiver and pressing the redial switch to make a call. Relay 2 is SPDT type (Single Pole Double Throw). When it energize, its NO contacts gives power to the tape recorder. In short, when both relay 1 and 2 energize, tape recorder plays the recorded message and telephone dials the number. 3 Telephone interface C1 0.01 100V POLY Telephone Lines R1 10K A Bridge IN 4007 x 4 ZD 12 V 1W R2 22K Tape Head phone Socket B Recorded message comes from the tape recorder is given to the interface circuit from the head phone socket of the tape recorder using a jack. The voice signals passes through R1, R2 and C1 to the bridge rectifier to the telephone line. Since the telephone line has 48 volts DC in the ON Hook state (reduces to 12 volts in OFF hook state) 12 V Zener diode is used to protect the interface circuit. 4 LDR Q12 R11K S1 IN4148 IN 4007 IC1 CD 11 4060 10 12 12 R3 100K 12 Relay 6V 100R C Reed Switch NC 7 12 C1 0.22 Reset R4 470R C C C2 0.22 16 D1 IN 4007 D2 IN 4007 RL1 9 9 8 SPDT Relay 6V 100R DPDT R2 1M VR2 100K Pot IN 4007 0 T1 BC 547 2 Magnet 16 10 IC2 CD 11 4060 NO NC NC NO R7 100K RL2 NO NC R8 1M T3 VR1 100K 1000 UF 25V 13 LED1 Green Active R9 100R R5 12K R6 150 R T4 BC 547 8 Trigger Long duration When door opens, Timer reed switch opens.Reset pin 12 of Detect light intensity IC2 goes low and IC2 starts Oscillation and activates timer Timer starts oscillations around 6 pm as indicated by flashingGreen LED. Output pin 2 becomes high after 4 hours around 10 pm. Gives power to the Alarm generator through T1.IC1 stops oscillation and output 2 remains high till morning and then resets Light Sensor BC 547 R10 100R 6V PCB Relay Relay Driver Relay Driver When pin 13 of IC2 becomeshigh, T3 and T4 conducts to operate relays 1and 2 .Hook of telephone is connected to the NC contactsand redial switch to NO contacts of the DPDT relay 1. Relay 2 makes contact and give power supply to the Tape Recorder which sends the voice message to telephone lines Visit dmohankumar.wordpress.com for Articles and Circuits. Website www.electroschematics.com Visit electroskan.wordpress.com for Hobby Circuits Front View TIP 122 B C BC 547 E C B E