In this project we will make GSM gate opener we will control GATE. We will use DC geared motors. We are adding password for security purpose. In this project we can control any electrical MOTOR through mobile or landline from any part of the country. In this project one base unit is connected to the basic landline in parallel with the land line phone.. When we want to control any electrical motor through outer phone then first we dial the connected mobile no., bell is ringing and after few bell phone is automatic on and switch on the base unit to operate. Now we press the single digital excess code, if the excess code is ok then unit give a tone pulse and switch on the base unit. Now again we press the switch on/off code to on/off any electrical motor. With the help of this code unit is on and base unit give a acknowledge pulse for on and off separately. in this project we can control number motors and different electrical functions through mobile.
In dtmf decoder circuit we use ic 8870 ic. IC 8870 is a dtmf decoder ic. IC 8870 converts the dual tones to corresponding binary outputs.
DTMF SIGNALLING. Ac register signaling is used in dtmf telephones, here tones rather than make/break pulse are used fro dialing, each dialed digit is uniquely represented by a pair of sine waves tones. These tones ( one from low group for row and another from high group fro column) are sent to the exchange when a digit is dialed by pushing the key, these tone lies within the speech band of 300 to 3400 hz, and are chosen so as to minimize the possibility of any valid frequency pair existing in normal speech simultaneously. Actually, this minimisator is made possible by forming pairs with one tone from the higher group and the other from the lower of frequencies. A valid dtmf signal is the sum of two tones, one from a lower group ( 697-940 Hz) and the other from a a higher group ( 1209-1663 Hz). Each group contains four individual tones. This scheme allows 10 unique combinations. Ten of these code represent digits 1 through 9 and 0. . tones in DTMF dialing are so chose that none of the tones is harmonic of are other tone. Therefore is no change of distortion caused by harmonics. Each tone is sent as along as the key remains pressed. The dtmf signal contains only one component from each of the high and low group. This significaly simplifies decoding because the composite dtmf signal may be separated with band pass filters into single frequency components, each of which may be handled individually
Look around. Notice the smart “intelligent” systems? Be it the T.V, washing machines, video games, telephones, automobiles, aero planes, power systems, or any application having a LED or a LCD as a user interface, the control is likely to be in the hands of a micro controller! Measure and control, that’s where the micro controller is at its best.
Micro controllers are here to stay. Going by the current trend, it is obvious that micro controllers will be playing bigger and bigger roles in the different activities of our lives.
So where does this scenario leave us? Think about it……
The world of Micro controllers
What is the primary difference between a microprocessor and a micro controller? Unlike the microprocessor, the micro controller can be considered to be a true “Computer on a chip”.
In addition to the various features like the ALU, PC, SP and registers found on a microprocessor, the micro controller also incorporates features like the ROM, RAM, Ports, timers, clock circuits, counters, reset functions etc.
While the microprocessor is more a general-purpose device, used for read, write and calculations on data, the micro controller, in addition to the above functions also controls the environment.
We have used a whole lot of technical terms already! Don’t get worried about the meanings at this point. We shall understand these terms as we proceed further large amount of built in ROM and RAM. In addition it has the ability to access external memory
Obviously you would
DTMF DECODER CM8870
DECODER IC 74LS154
RELAYS- 180 OHM 12V
TRANSFORMER 12 V
DECADE COUNTER IC 4017
COPPER CLAD BOARD
UMPS COMPILER,ORCAD, PROGRAMMER
|CIRCUIT AND THEORY ARRANGEMENT|
|CHECKING AVAILABILITY OF COMPONENTS|
|COMPONENT INSERTION AND SOLDERING|
|REWORK OR TROOUBLE SHOOTING|
Advantage and applications:
1. farmers have to go to fields to start pump motor early in the morning. With the help of this project they can easily control the pump. At any time.
2. In some areas because of lack of water sources, water supply is for very small time. With the help of this project employees doing job can switch on/off their house’s water tank motor.
3. motors in remote area can be control
4. Antenna direction can be easily controlled