Theremax Construction Project

Pics of my test setup for a Lev Antenna made with clear PVC pipe
http://www.flickr.com/photos/15226899@N07/3154462871/

Your Lev Antenna looks beautiful.

Look forward to to hearing about your results.

Snuffy: The exact same thing happened to me with the diodes! It took me a long time to sort them out!

Scorch77

Hey Scorch,
How are your cabinet plans going? Do you have access to wood shop at school, maybe interest a teacher in setting up the cuts and holes for you?
The Theremax kit cabinet is nice wood, hard and clear (no knots). I've been sanding and drilling and sanding and sanding, then got the pieces stained this past weekend. (Minwax dark walnut 2716.)
Over the past two days, I've lined the inside of the panels with copper foil for shielding. Aluminum foil would work just as good, but i went the extra money for the look (don't ask, okay, 25 bucks for .001" x 12" x 5') plus shipping.
www.nimrodhall.com
Check out my gorgeous pic of the parts leaning up against each other and glowing like the Mcguffin (briefcase) in Pulp Fiction:
http://www.flickr.com/photos/15226899@N07/3178504239/

[i]Over the past two days, I've lined the inside of the panels with copper foil for shielding. Aluminum foil would work just as good, but i went the extra money for the look (don't ask, okay, 25 bucks for .001" x 12" x 5') plus shipping.[/i]

Ouch! This won't work! Your shielding adds far too much capacity so that the antennas will not longer detect the 0.xx pF variation when you move your hand. That's why theremins are always in wooden or plastic and never in metal housings.

I agree with Thierry that the copper foil is not a good idea. The shield concentrates the RF within the enclosure and the two pitch oscillators will tend to detune more as you put the enclosure top on or they will bind more readily, creating a wider Null point. The oscillators operate 180 degrees out of phase and are in phase when holding at the Null point. The shielding would also cancel a lot of the theremin response besides “warping” the audio wave shape.

Christopher
.

Ha, ha, ha,,, sonofabitch! I guess I took some back advice from the PAiA website: "Metal cases can be used but may be problematic since the antennae will need to pass through the case without making electrical contact (rubber grommets would work here) and/or mechanically attached to the case, also without making electrical contact (shoulder washers come to mind here)."
Peeling that foil off with a razor blade should be fun. Reminds me of a cooking segment on the Bob and Ray show. "Cube a marshmallow... and that should keep you busy!"

PAiA may have a good reason for the metal enclosure that I am not aware of, their instructions should take priority over any other. So don’t whip out the blade to soon, maybe try it. Theremins like to make people suffer you know!

Also, is the foil actual copper and can be soldered to with an adhesive back peel off liner? I might try it on something in the future, where did you purchase it?

Christopher
.

Thierry wrote: [i]That's why theremins are [...] never in metal housings.[/i]

I thought the tVox Tour had a metal housing?

Hmmm...

sorry for imposing you this copper peeling.

This situation remembers me a main theorem in the education of my four daughters: "Your Dad has 32/36/40/43 years more life experience than you. Ask him BEFORE!"