26-01-2012, 02:42 PM
CLAP SWITCH
[attachment=16654]
General Description
This is a circuit that can be used to turn a device on
and off by sound only, hand clapping, whistling etc.
Can be used to turn the lights on and off, in security
systems. When triggered the circuit will stay in the
on or off condition till it is triggered again.
Technical Specifications -
Characteristics
Working voltage : 230V AC
Current : 60mA
Contact Rating : 3A/ 6A as per the kit selected.
Warning
VISHA kits are sold as stand alone training kits.
If they are used as part of a larger assembly and
any damage is caused, our company bears no
responsibility.
How it works
The circuit contains two stages first of which is a
preamplifier using transistor Q1 for greater amplification
of the microphone signals. The second circuit contains
2 transistors Q2 & Q3 connected as a FLIP-FLOP. The
flip-flop is triggered by the preamplifier’s output and it
triggers in turn the output transistor Q4 which controls
the relay. As you can easily see with each change of
state of the FLIP-FLOP the output transistor will also be
forced to change state being either on or off and this
