GSM Based HOME AUTOMATION using electronic relays

1. GSM based Home Automation
Name : Rajneesh Salgotra
EnRol : 163/2010
Roll : 31
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2.  GSM
 DTMF
 DTMF DECODER
 MICROCONTROLLER
 RELAYS
 COMPLETE CIRCUIT
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3.  Now a days , GSM services easily available to
everyone .
 And You need not to carry a different remote
controller .
 Mobile Stations are already a multipurpose
devices , so why not to incorporate one more
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4.  Dual-tone multi-frequency signalling (DTMF)
is used for telecommunication signalling
Between telephone handsets and other
communications devices and the switching
centre .
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1209 Hz 1336 Hz 1477 Hz
697 Hz 1 2 3
770 Hz 4 5 6
852 Hz 7 8 9
941 Hz * 0 #

5. 5
1209 Hz 1336 Hz 1477 Hz
697 Hz 1 2 3
770 Hz 4 5 6
852 Hz 7 8 9
941 Hz * 0 #

6. 6

7. 7
O
U
T
P
U
T
INPUT

8. 8

9. 9

10.  We have the decoded Hexadecimal Number
corresponding to the pressed key
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NOW Microcontroller to take
Decision .

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I
R
O
C
O
N
T
R
O
L
L
E
R

12.  Problem :
The output of Microcontroller is of very low
power highly insufficient to operate electrical
loads .
So we use relays for controlling electrical heavy
loads through Microcontrollers .
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AC POWER

14. 14
+Vcc

15.  Remote controlled ROBOTS and APPLICANCES
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16.  No feedback
 GSM connection for the operation
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17.  http://pdf1.alldatasheet.com/datasheet-
pdf/view/77085/MITEL/MT8870.html
 Mazidi, Muhammad Ali, The 8051 Microcontroller and
Embedded Systems
 SOLID STATE RELAY HAND BOOK
 http://chipscity.com/downloads/Projects/GSM%20based%20C
ontrol%20System.pdf
 www.wikipedia.com
 8051 MICROCONTROLLERS by SATISH SHAH
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