Magnetic Transmitter

Did you ever think it would be cool to transmit music wirelessly?
But you don’t have the knowledge to make your own wireless transmitter.

I put forth a simple way to do this all without any complicated circuitry.

 

When current passes through a wire a small magnetic field is produced. The direction of the “flux” lines or magnetic field lines is dependent on current.

We can take the wire and shape it onto a loop to concentrate these lines.

How do we make these flux lines into something useful?
This is the easy part. We know that passing current into a wire produces a magnetic field, so we can transmit with that magnetic field.

Music is represented as a constantly changing magnetic field; if we pass that music into a large coil of wire we will get a magnetic field that will be our music.

The reverse is also possible. By collecting a changing magnetic field we can produce current and voltage. This current and voltage can be collected and amplified so that we can hear what is happening in the transmitting coil.

I will demonstrate how I achieved this.

I used an ordinary audio amplifier and passed the current through a large loop of wire. The larger the loop the better, because you spread out the magnetic field lines which is more important than the current flowing through the wire.

I used a average of one ampere of current through my wire.

My loop of wire was hung from a nearby tree to maximize its size. The wire is highlighted in red.

My receiver is around 200 loops of wire on a 1 1/2 inch diameter cylinder. The larger the cylinder the more flux lines it can capture and the further away it can be placed. But there are practical limits to its size.

The amplifier is a high impedance type. This will amplify the current coming from the coil so that I can hear the magnetic field.

The receiver coil needs to be pointed at the transmitting coil in order for it to work properly. The flux lines need to pass through the center of the coil to be received properly. (Demonstrated in video below)

 

Movie (Large File) 10mb

The field is strongest inside the coil, knowing this you could wrap a loop of wire around your house and have music everywhere in your home.

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Project By: Robert Balonek

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