Hi.
I have a class where we were supposed to make some new product using electronics. Our group decided to make a key finding device that one can hook on to keys and small objects. We didn't really consider the possibility oif it already existing.
Therefore, we decided to have 4 buttons on a transmitter, that each worked with a different receiver. Now, the way they communicate may be radio waves, or is there a different way of doing this wirelessly? Is there a single component able to do this radio/wireless communication? Thanks for all help in advance, any schematics for something like this would be amazing!

-T

 

We didn't really consider the possibility oif it already existing.

I'm pretty sure I've seen one of these. Reverse engineering can save a ton of time.

You need to better define what you want to do. Range, battery size, etc. I think you might use garage door transmitter technology for the encoding, but that's just a speculation.

 

This was mentioned here:

http://forum.allaboutcircuits.com/showthread.php?t=69050&highlight=finder

Check out:

http://www.keyringer.com/