Simple OP Amp radio

This is just what you think it is, a radio made with an op amp. This is just as accidental and simplistic as my other radio instructable (the 555 radio) and actually made me ask myself if I was just an RF magnet or something. There is only about a handful of parts you need and while somewhat pricey they are all obtainable at Radioshack. So if you feel like making your own simple radio for field reception. This is a good choice (if you've seen my 555 radio instructable you'll bee happy to know I was able to get two decent signals from two stations this time). For those who want to see the 555 radio follow this link here: http://www.instructables.com/id/555-timer-radio/        - otherwise let's get to building!

Step 1 Parts you will need

Alright all you'll need for this project are the following:

x1 LM386 op amp IC chip
x2 1000 microfarad capacitors (any capacitor works but it's louder with these)
x1 100 microfarad capacitor
x1 8 ohm speaker
x1 9 volt battery
x1 project board
some wire (I used about a foot and a half)

optional - a wire parabola (such as a mini fan cage, a colander, etc.)

And that's it. Of course this isn't a crystal clear signal, but I think you'll be surprised how easily you can understand the voices and the music is pretty clear too, there is some minor static but after listening for a while it's barely noticeable.

Comments

[shortdiesel]

I did an experiment with this and I got FM and AM radio stations on my lm386. Pretty easy setup so I won't make an instructable unless it is requested:
Supplies:
1 breadboard
1 lm386
1 stripped USB wire (for power...instead of 9 volt)
1 8 ohm speaker
some hookup wire unstranded

Connect pin 2 to ground. Connect pin 4 to ground. Connect Pin 5 to positive side of speaker and connect negative side of speaker to ground. Connect Pin 6 to positive power. Connect antenna to pin 8 (I've used a combo of things for antennas, but an alligator clip hooked to a small piece of wire will do). Plug your USB power supply directly from computer to the breadboard. Presto! You now have a radio.

I have no idea how this happened, and it only works for me if I use my computer's USB cable as the power source. Pin 3 also works for the antenna but it sound very fuzzy.

[LaurelMakers]

what kind of antenna wire is used here? it doesn't seem to be included on the parts list.

[aliyevzaur1989]

So how exactly do you tune it?

[tinstructable]

A joule thief adds power for an LED, is there any way possible it could be used to amplify a speaker?

[jrig]

i think your speaker is messed up

[josh1001]

if u want i choose a station u should use a tuner circuit which consist of a capacitor and inductor (in parallelwith each other) and place it before the antenna. Preferibly a variable capacitor or inductor or both.

[josh1001]

if u want i choose a station u should use a tuner circuit which consist of a capacitor and inductor (in parallelwith each other) and place it before the antenna. Preferibly a variable capacitor or inductor or both.

[lxkarthi]

u said, it is a radio.. Is it FM or AM? which frequency? plz..

[MacDynamo]

I'll be honest, I'm not entirely sure. I fairly sure it is AM because magnetic fields disturb it so much but it could FM because I had some sort of rock station. The frequency is also kind of unknown to me too, since the stations change but the op amp isn't exactly an oscillator I so wouldn't have a clue what formula you'd use to figure it out. I hope this helped because this is really surprising to me too.