Aluminum foil radio?

Question

A past teacher of mine told me about a friend of his that could make a music radio with aluminum foil and change the music station by sliding the foil back and forth against another piece of foil or something. I never got much details about it... Does someone out there know how to make a radio out of aluminum foil? If so, please tell me how I can make my own... Not knowing will make me go crazy... Thanks!

Answer 1

I've used aluminum foil as an antenna, and two pieces seperated by a sheet of plastic as a tuning capacitor, but I've never heard of that trick. maybe he was referring to the tuning part, there's no way a sheet of foil will demodulate (detect) a signal.

Check out the website below for some tips.

Answer 2

You can't make it entirely with aluminum foil, but yes, it is possible.

You can make a coil - which is any metal wound on a cylindical fashion. You can make a capacitor which is too metal opposing each other. When you connect both of them in parallel, you get a resonance circuit - ie. dial on the radio.

From there, you can use a diode and (for simplicity sake, cutting out the details) extract the audio. Feed that to a high-impedance earphone. voila... Crystal Radio!

To make an aluminum foil capacitor, you put aluminum foil on a flat surface. Place a sheet of plastic over it. Then place another sheet of aluminum foil on top of it. Basically you made a sandwhich.... When you slide the top foil, you change the part that overlaps the bottom. Combined with a coil, you can tune to different station that way.

You need to look up (web search) on Crystal Radio. You can find lots of hits.... That's basically what you are making.

Answer 3

I know a little bit about electronics and was Radioman in USCG for ten years.
Never heard of radio made with just aluminum foil.
Somebody must have been confused cause I can't see how a radio can be made with just tin foil.

The simplest and I mean simplest radio design I have ever seen was the FOXHOLE RADIO....used by U.S troops in WW2.

Here excerpt from link and link to FOXHOLE RADIO
Foxhole Radios
by Don Adamson
If you appreciate ingenuity, simplicity, and like instant gratification from your radio projects, then you ought to spend a few minutes building your own foxhole radio.
Foxhole radios were built by GIs in World War II from materials they had easy access to in the field. They usually consist of just a coil and a detector. They use a point detector, the chief component being an ordinary razor blade.
Justin Garton wrote a letter to the editor of QST, printed in the October 1944 issue:

Here is some more information on the foxhole radio sets used by the boys on the Anzio beachhead. In the daytime they could receive stations from Rome and at night Nazi propaganda "jive" programs from Berlin. Here is the diagram:

http://hometown.aol.com/djadamson7/articles/foxhole.html