so, just how tricky are theremins to build... correctly?

[runmikeyrun]

Thinking about it, but not sure if these buggers can be hard to fine tune or are durable enough to go in a road case, let alone the difficulty learning to use one!

[johngreene]

Not trying to be a smarta$$ but this is kind of like asking, "So, just how tricky is it to learn how to swim?". For some people it is impossible, for some it is achievable with much difficulty, with some it's a piece of cake.

In a nutshell, it involves low frequency RF. Without an oscilloscope, it will be difficult to get working. If you haven't done any kind of radio experimentation before, and don't have an oscilloscope, you're probably in the 'achievable but with much difficulty' group.

--john

[Paul Perry (Frostwave)]

I personally found it so difficult to get a RF theremin going, that I eventually switched to an infra red based design (modulating the output of an infrared led at a couple of hundred Khz and usign the detected reflected beam to do the control).
On the other hand, the web is jammed with successful DIY RF theremin designs.. but if you want to put one inside a guitar, it might not be so easy..

Anyone wants to play theremin & guitar at the same time, put an oscillator inside a wah shell & do the 'theremin' with your foot. That leaves both hands for the guitar, which is nice.. I mean, how else are you going to control the theremin

[Bard Morons]

I've been fooling around with a theremin type device for awhile now.  I get very inconsistent results on my breadboard.  It's working, but it's not working the same each time... go figure?  I'm certainly no electronics genius, in fact, I'm not very good at all.  So, I guess I'm saying that it's possible, just not easy in all likelyhood.  I'm trying to use a Basic Stamp to smooth my results out.  Hopefully that should allow for a more consistent end result, but it's still in the early stages.  Good luck if you decide to take this up!

[birt]

look at art harrison's desings. they are quite easy and sound great.

his minimum theremin is easy but you should definatly use a multiturn pot for the pitch null calibration. otherwise you need to recalibrate it A LOT.

here's one i made: http://sic.fotopic.net/p35265779.html

[johngreene]

I've been fooling around with a theremin type device for awhile now.  I get very inconsistent results on my breadboard.  It's working, but it's not working the same each time... go figure? 

When you say 'breadboard', you don't mean one of those socketed protoboards do you? With a theremin you are moving into RF frequencies and I wouldn't prototype with anything other than the 'dead bug' approach on a solid sheet of copper. A good low impedance ground will eliminate a lot of problems. Ground issues are orders of magnitude greater than what you are familiar with at audio frequencies. And keep getting worse the higher in frequency you go.

--john

[thumposaurus]

If you want it in kit form the PAIA one is nice.  It will need tuned occasionally but it normally takes me no longer to tune it then it would to tune a guitar.