Proximity sensor - Weekend project

Hello, this is my first post. I've been looking around in several web pages and i couldn't find anything like what i want to do. I want to do a proximity sensor system that detects the distance between 2 transmitters, with a light that glows more or less, or a LED grid (a previous project, a conductivity meter, was done with one using a chip).
I don't care witch technology it uses, all i want is to:

1- be portable and small
2- be simple and battery-friendly
3- Have a good range (something logical, because i found a prox. sensor that works the way i want, but its with infrared and the range is 6-9 INCHES) and, if possible, not need visual contact with the other transmitter.

Remember this is a simple weekend project, there's no need to make it something impressive.

Sounds a lot like a stud finder.

Meoiswa said:

I want to do a proximity sensor system that detects the distance between 2 transmitters,...


3- Have a good range (something logical, because i found a prox. sensor that works the way i want, but its with infrared and the range is 6-9 INCHES) and, if possible, not need visual contact with the other transmitter.

Click to expand...

It is not clear to me what you want. What range do you need?

Was the 6 to 9 inches with infrared too far or too short a distance?

If the objects are not line of sight, what is the medium through which detection must occur?

Finally, you mention finding the distance between two transmitters. What are they transmitting, e.g., sound, light, vibrations, RF, heat?

John