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Where can we find more detailed pictures of the Tesla Radio? Answered

We are trying to build the Tesla Radio for a science fair and can't get any noise from it.  Is there any other photos that we can see to check our connections?  The diode is getting no reaction.  We read that we have to hit it from a specific direction but none seem to work.  Any suggestions?


I believe you are talking about my Spooky Tesla Spirit Radio instructables project. It makes sound when the 1N34a diode receives light from a certain direction.

Kinda late for your science fair project (next time contact me directly, hehe) but the answer to your question lies in several areas.

First, make sure the basic schematic and parts layout is followed.(see step 1...)
You should be getting some sound from the radio. You must have sound software to increase the gain of the signal substantially. I use a Mac and Audio Hijack Pro. I haven't found an equivalent program on the PC.

Essentially, the circuit must be made super-sensitive by jacking up the gain so far that even a slight disturbance will set off a sound signal. There should at least be some sounds, like hearing a weak radio station, or hearing a response from things like electric motors, or sounds by holding the radio close to the monitor.

A standard light bulb should give a humming sound from the diode when placed close to it. It may require a stronger laser, like my rpm meter, to register on the diode.

Once you know the radio is "sensitized" and active, then experiment with direction of light one way or the other along the length of the diode.

To get sound from it you are going to have to use very sensitive, high impedance headphones or some kind of amplifier.

And please don't make any of the Tesla transmitters.  They have almost no selection and will broadcast all over the spectrum causing tv's, radios and cell phones to be interrupted and the agency that deals with radio laws in you country will hit you pretty hard for that.