BCBCVVBCV BCBCVB: CBCV BCVBC
BCBCVVBCV BCBCVB: CBCV BCVBC
BCBCVVBCV BCBCVB: CBCV BCVBC
xvdffbcvcc
bcbcvvbcv bcbcvb
cbcv bcvbc
Cbcv bbccv
INDEX
INTRODUCTION
COMPONENT LIST & ITS DESCRIPTION
CIRCUIT DIAGRAM & DESCRIPTION
PRINTED CIRCUIT BOARD (LAYOUT)
SOLDERING
TROUBLESHOOTING
ADVANTAGES & DISADVATAGES
APPLICATIONS
REFERENCES
INTRODUCTION
This circuit is built around a 555 timer configured in
monostable mode means it will be stable in one state and
action will require to change that state. Thats why we have
utilized this property to make touch on and off switch. With the
help of this circuit you do not require to move from your place to
on and off the device just touch with the help of finger device
will become on and off automatically. And important feature of
this circuit is you will not get mechanical shock which we
sometimes get while using the normal switched.
IC1-741
IC2-CD4027
DIODE D11N4007
TRANSISTOR T1-BC547
R1-3.3M
R2-1M
On/Off Switch-Push to on switch
Relay-6V, 1 C/0
CIRCUIT DIAGRAM
WORKING OF WIRELESS SWITCH
Assemble the circuit properly and apply power supply. To ON the connected
device, put your finger between touch to ON point and to off the device put your
finger between touch to OFF point.
When power supply is provided to circuit device connected through relay remain
ideal because voltage at pin2 (trigger pin) of IC is low but as soon as you touch the
ON switch pin 2 of IC1gets the trigger signals and out pin3 receives high input and
output pin 3 goes high which will make the transistor T1 into conduction and the
relay connected through it energize and device connected across relay becomes
ON.
At this point voltage at pin 6 is zero. Similar action takes place when you touch the
OFF switch. This circuit works by latching a relay to ON state with push of a
button and with another push latch is released and device become OFF. It is
working similar to a flip-flop state.
If you are getting problem in getting touch pad then in place of touch pad you can
also switch. In that case use push to on switch so that when you press the switch it
will make the connection and ON and OFF the device according to the
requirement.
You can also use the touch plate from the old toys and doorbell . Touch pads consist
of a small carbon block mounted in silicon rubber and when the button is pushed, the
carbon block make contact with the pad and reduces the resistance between the two
interleaved tracks. The pads which are available in market are already protected
from corrosion and have very good sensitivity to detect your finger response. When a
finger is put between points, the resistance between the lines drops between 150k
and 850k, depending on the pressure and presence of moisture in the finger and it
will vary from person to person.
1. As use of relay which makes the switch bulky than any ordinary
switch.
2. Sometimes false switching may takes place.