The idea is very simple, the signals are in the air. You need some electrical/electronics components to receive the signal. Adjust/tune the signal to find the best radio signal, and then pass through an amplifier. Eventually you need to pass the signal to a headphone to be able to listen to it.
Technical:
The idea is, you use transistors to detected FM modulated radio signals. Then you use coils and capacitors to tune to the strongest radio signal available. then you pass this signal through an amplifier. Eventually, the signal can be passed to a headphone for listening to the music.
You can get a very basic FM radio receiver circuit at:
http://www.electroschematics.com/5150/tiny-fm-radio/
This is one of simplest and smallest FM radio receiver that can receive the FM stations available locally.
For transistors you can use: BF 494 [two of them in the circuit]
Coil: L 18 SWG, 4 turns air coil
Capacitors: 22 pF, 0.22 pF for tuning, also another 0.1 microF, 220microF
Amplifier: LM386
If you need details on the radio signal stuff, you can read the page
How FM/AM radio works: http://stereos.about.com/od/stereoscience/a/AMFMRadio.htm
a comment from a user about the circuit:
”
This is a nice little circuit! It is quite tricky to get it to work, but it is worth it. I attached it to my buildings TV antenna and use a big variable capacitor (~400pF) with a ~25 turns coil to receive international radio stations from around the world! My suggestions to anyone who wants to try this: replace R1 with a pot to fine tune (I use a 10k pot in series with a 15k fixed resistor). And use pins 1 and 8 of the LM386 to raise the gain when receiving weaker stations.
” From: http://sitestree.com/?p=305
Categories:Web Development, Root, By Sayed Ahmed
Tags:
Post Data:2013-05-31 18:17:47
