# Question on Wireless Switch

Discussion in 'General Electronics Chat' started by bhaazee, May 13, 2012.

1. ### bhaazee Thread Starter New Member

Mar 3, 2012
19
0
Assuming that a light bulb is connected to an AC power source through a simple electrical switch, its easy to understand how the circuit works.

But now, I "also" want to control the switching activity wirelessly (via IR or Internet or BT, etc.). This means, the same light bulb should be able to be controlled either through a mechanical switch or through some electronic circuit.
How can this be made? (Although the light bulb in this case, will be controlled via two switches I believe the way both the switches are connected is not like a two way switch). I believe this is the way, how an home automation system works.

I just want to understand the working logic behind. Hence I have put forth my query.

Regards

2. ### MrChips Moderator

Oct 2, 2009
12,234
3,283
So you have an electronic controller to control a light.

The light can be operated from two locations.

Draw the boolean logic table for this function.
You have two inputs, one we label A and the second we label B.
You have a single output we can label X.
Fill in the values of the table for X for all possible conditions of A and B.

If you are not familiar with boolean logic you can read up on this in the AAC Tutorials:

What you are looking for is called an Exclusive OR function or gate.

3. ### bhaazee Thread Starter New Member

Mar 3, 2012
19
0
remembering my basics which I studied during bachelors

If possible could you illustrate me with some hardware example. Simply put, I was speaking about a two way switch. But I am asking if there is any electronic device (say some kind of transistor or MOSFET kind of electronic device) that performs the operation of a two way switch.

Last edited: May 13, 2012
4. ### MrChips Moderator

Oct 2, 2009
12,234
3,283
The answer is in post #2.

I am referring to a two-way switch.

The solution is called an Exclusive OR gate.

5. ### bhaazee Thread Starter New Member

Mar 3, 2012
19
0
Sorry. Have only learnt about logic gates. Haven't really seen such physical gates. Hence could not grasp your point.

Thanks again

6. ### Bernard AAC Fanatic!

Aug 7, 2008
4,140
393
Might consider a common receiver feeding a toggle flip-flop which controls the light. One push of either transmitter, & light goes on- second push light goes off.