This is an instructables.com project submitted by masteruan. As a first step, you can create this circuit on a breadboard and try the circuit before solder it on protoboard. After the test you can use a protoboard to connect the attiny85 to leds and antenna.
This is a simple tutorial to create an EMF detector. You can use Arduino for this job, but is better use a microcontroller called Attiny85. It is possible program it throe the Arduino interface.
Attiny85 EMF detector – [Link]