Expanding Theremin's range

Hello, I have a project in which I would like Theremin to react to people walking in a room. I was wondering if that is possible and if yes, what is the way to expand? Add bigger antenna? Room would be around 5x5m. 

Thank you

Ignas

Make a cylindrical antenna, roughly the same height and diameter as a person, and put it in the center of the room.  Or use a plate to make it more directional.  Use higher frequencies than normal, say 1 MHz or higher, for the oscillators so as to increase the heterodyned sensitivity.  Don't pad or load the antenna with any extra oscillator capacitance, use the intrinsic self-capacitance of the antenna as the C in the LC tank.

[EDIT] The antenna should be raised a foot or two to minimize capacitance with the floor.

If you have some basic skills use an optical theremin approach, this eliminates antenna tuning and theremin pitch drift. Let the field of view and room brightness control the response. Use multiple light sensors for a wider or circular field, it is very cost effective. You might even trigger a midi response for better sounds.

A regular theremin will have disappointing results in this application.

Just remember to have fun.

Christopher 

Thank you for the responses. I have a theremin like that , but I can't make any changes inside of it because it is not mine. I guess adding cylindrical antenna is not going to help? 

Would it be possible to make this work in a bigger scale ? 

Optical might be an option, and I am interested in different results than precise ones :) 

Thanks

Hey there,

In my theremin journey I studied many possibilities without copying anyone. I am very stubborn, no wait all of us here are very stubborn and ornery. After a year no one contacted me on one of my simple optical designs so I abandoned the research. The idea of Optical is to develop it into its own design of musical instrument with a nice sound. Most of the creative crowd moved over to facebook I guess, a place I have never been. The idea was to improve the lack of fluid movement in the Tannerin.

Optical Theremin       <= The Sound of This

I may return to this in the future, after I find a local musician!

Christopher

"Would it be possible to make this work in a bigger scale ?"

Yes, but there's a lot of capacitive padding across the antenna that might need to be removed to make it as sensitive as possible.  If you want range you need a big antenna, a decent voltage swing across it, and as little padding as possible.

I am very beginner at this, just starting to work with electronics, and honestly I want to make this work with as little time spent as possible. Basically would it be enough to add bigger antenna to Moog Theremin to create reaction(precision is not important)?

"Basically would it be enough to add bigger antenna to Moog Theremin to create reaction(precision is not important)?"

That's a possibility, though you would definitely need to open it up and re-tune it, which can be a pain in the ass.

Can I ask you how can I re-tune it? Which parts would it be?  

Really, thank you for your time. 

You will destroy your EtherWave Standard learning why using it is not a good idea. Thierry are you out there?

At the most you might get a tick-tick sound in the outer field and then have to re-tune it constantly. You would need to use a remote tuning pot outside the field, maybe 3 meters or more away.

Christopher