can any one help please i need to build a very small receiver & transmitter as slim as posible.they would need to have sound to go off when they are 10 feet apart i will keep my little lad close..thanks. i am very new to this so if i break any rules please let me know as i am a bit thick that way...

 

Are you saying that you want the receiver to emit some audible alarm when the transmitter has moved 10 feet away from it?

 

No rules are broken that I know of. Welcome to AAC.

I thought there were commercial versions of those out there? The exact distance will vary.

 

You might be able to use bluetooth. My cellphone phone shows an alert if/when a paired device goes out of range. Put one of those cheap earphone things in a pocket.

 

It would be much better to use a commercial radio, connect something to the earphone jack that would sound an alarm if the signal fades away. Transmitters are typically easy.

The more experienced you are with electronics the easier it will be to make it small. Soldering is a skill involving practice. Let us know how you want to approach it, and the location in the world where you are at. It matters as to parts you can get.

Really small involves printed circuit boards.