College lab project for Theremin

Hey I'm building a theremin with two other lab partners for a final project in my EE40 class. So I was wondering if anyone here knew a theremin schematic that would fit our needs.
1. We have a month to do it so it needs to be relatively simple. Something that we could complete in around 30-50 hours (I'm not sure how much time we'll have)?
2. I'm sure we're not allowed to use a kit, even if we do modify it so kits are out of the picture. 3. It also needs to stay within budget, $500 is probably our limit, before the lab TAs start getting angry.
4. It's just a personal thing, but I'd rather not work with a voltage high enough to kill me...
5. All of the materials need to be easily accesible, stuff we can buy on Digikey or at a local store would be best.

With all that in mind any suggestions?

Oh yeah, how difficult would it be to alter the sound a theremin makes into sounding like a piano or drum?

What exactly is your definition of a theremin?

Whatever it may be, creating a synthesizer with gestural control is probably way outside of your requirements. Gestural control and percussive sounds (like piano or drums) are not a good match. They generally require a MIDI controlled synthesizer, which does not blend easily with gestural control.

I don't know what a EE40 class is, so I cannot know your actual requirements and faculties.

But perhaps the following could help:

Last spring I developed a pitch-only theremin with one antenna (volume control by a potentiometer, not by gesture) with two hartley oscillators, an active FET mixer and an integrated audio amplifier, which can be build easily and entirely on a breadboard, for a group of Swedish high school students. The material costs are below 100$.

If you are interested in this, you may contact me by email theremin[at]tfrenkel[dot]com

Sorry, Thierry, but that pitch only "theremin" with the volume potentiometer is not a theremin. At best, it is an ETHERPHONE - the name that Leon Theremin gave to one of his early prototypes that was ultimately rejected in favor of the instrument in which both VOLUME AND PITCH are gesturally controlled and that we now recognize as a theremin.

The Etherphone did survive and was played for many years by the Russian musician, Konstantin Kovalsky. He has been succeeded by etherphonist Olga Milanich.

It should be pointed out that the reason a potentiometer (controlled by the player's foot) was used for volume control was to free the left hand so that it could manipulate a cutoff switch for articulation. The "Electronde" of Martin Taubman was an adaptation of the Etherphone in which the articulation switch was held in the player's left hand.

The big question here is: at what point do we stop calling an instrument a theremin? For many people today, a theremin is anything that makes vaguely scary SciFi sounds.

Sorry for the late reply. Our group is planning on building a moog etherware theremin or someother theremin from a kit then constructing a robot to play a simple song with it. If anyone is an expert on robots here I'd appreciate your opinion on how possible this project would be and the easiest way to construct a robot would be. If not, could you give us a rough estimate on the time it would take to construct a theremin from a kit?

I appreciate the offer for the pitch only theremin, and I'd love to have the schematic if our plan falls through.

You can put together an Etherwave from a kit in a couple of hours (that does not include the time it takes for fancy cabinet finishes).

Our Theremin World founder, Jason, knows about how to construct a theremin-playing robot. He did it very successfully back in the mid 90's.

Awesome! How could I contact Jason?

"Awesome! How could I contact Jason?" - Wendeli

Perhaps if you click on one of the links above that says "Contact Us". ;-)

Yeah I realized that right after XD It doesn't seem like he'll reply for a while though :/ Anyways what do you think of this plan? It's still in rough draft mode so lots of opinions would be appreciated.

We plan to build a relatively cheap theremin and adjusts some of its parts to produce a better volume and pitch control. We've found the schematics online, so this part shouldn't prove to be too difficult, especially since we're modifying a kit.

Next we plan to build a theremin playing robot that operates with two "hands", one moving left and right and one moving up and down. The left and right hand would move on a rotary motor that allowed it to quickly change the hands distance from the antennae, and all the distances would be programmed in.

The volume control hand would probably function in an on off mode, where it would turn volume off as the pitch control hand adjusted notes. This would work with two levers or whatever you call it, where the bottom lever retracted whenever volume was needed and came back as pitch was adjusted. We're fiddling around with a few ideas about how to do this and whether or not it would be reacting to the pitch control hand to do this or also be programmed, so no definite idea yet.

What do you think?

Also, since we don't have a theremin yet could one of you guys answer these questions?
1. If you have a volume control antennae and no hand above it, how does volume react?
2. Does the distance for changing pitch change for each theremin depending on it's size or is there a general distance that your hand can be that works for all of them?

Thanks for any help

1. When no hand is above the volume loop, the volume will be at maximum.

2. The tone spacing varies within the pitch field, depends on temperature, humidity, moon phases and external/environmental capacitance. No way to find "fixed" points. A robot would need a cybernetic loop detecting the actual audio frequency, comparing it to the desired tone and appropriate correction movements, in the same way as a human player would do it.