There are a lot of RF energy(unused) in our environment, by TV , radio channels, etc.
We can capture energy of any wave by tuning same frequency resonating coil, but we can simply capture radio signals by a stick antenna and even drive a LED by that if we get strong signal.
What we need?
- Stick Antenna(Brass made) — 1pc
- Insulated copper wire — 100-150feet (36swg)
- Grounding
- 0A79 diode and LED(for led driving)
- MW radio antenna coil with ferrite rod
- A 500pF tuning GANG
The setup is simple. You need to setup the antenna very high, most probably in top roof or in top of a bamboo and make sure it’s not grounded and isolatedly fixed. Then connect enameled copper wire to antenna and take it to your circuit section.
In the circuit section, connect one end of MW antenna’s coil(large section of 450Turns) to antenna and other end to ground. Connect both ends to the 500pF gang and tune the gang and ferrite rod to a local MW station.
For tuning, use the 0A79 diode to rectify in half wave mode, the voltage output becoming positive from antenna’s end and connect GND and that pin to uA meter and measure the highest current. In tuned position, it will show highest reading. hen just seal the coil on ferrite rod by wax and connect a LED on the output and see it lighting.
Cost:(INR)
- Antenna: 15/-
- Wire: 10/-
- Diode, LED, Coil, Rod, etc: 10/-
Total: 35/-, that's around 0.5 US $, pretty cheap yeah ! Enjoy building this project.
Wesley says
What id you used a cat whisker diode made from Uranium, Bismuth and Thorium doped Galena?
I know a chunk of radium bromide brought near an antenna enhanced signal pickup based on an article back in 1916.
Arnab says
Very interesting ! And from where you're getting that vintage radioactive whisker diode ?
kumar says
it should have been nice if whereto buy is specified.