What's happening???

So I was playing my theremin and I walked away to change the song I was playing along to and I was keeping my hand near the volume atenna so it wouldn't become really loud and I somehow noticed that I could movey hand away and not have it be really loud. I know this isn't new, but whatever. Anyway, I was standing around changing the song my hand no longer controlling the volume and I heard a radio playing. I wondered whose it was so I went around to the rooms around mine and neither theirs nor mine was playing but the radio was still playing. Doing this I also realized that the sound was coming from my room. I wasn't sure from where but then I realized it was coming from my amp!! Then when i put my hand close the volume attena the radio went away!! What's happening!!!??? I'm assuming that somehow the theremin's atennae are picking up the radio either from someone else or an actual radio signal. I'll be able to see later if the radio is still there because it's unlikely that someone will have been listening to their radio all day. Has this ever happenend to anyone before??

Your Theremin is picking up the radio - You have the pitch null-point set so that there is no frequency difference, and therefore no audio from the Theremin.. You are away from the volume antenna, so the internal amplifier (VCA) is giving maximum gain.. The radio signal coming in on the pitch antenna, and being tuned by something.. there are plenty of places this could happen.. Then these radio waves (which will be amplitude modulated [b]most[/b] likely are being rectified (probably by the mixer diode) and low level audio produced.

There are strange things that can happen with (particularly) AM radio.. even filling in teeth have been known to produce signals, and spooky things like toys starting to play the radio are not uncommon.

That's sooo cool!! That's incredible! Thanks for filling me in! Do you know how the specific radio signal is picked, and if it could be changed?

It would be much easier to buy a radio if you want to be able to change the channel.

It's really not incredible at all, especially if it happens to be AM radio. AM radio signal can easily get into all sorts of stuff. When I was in college, I lived in Boston, and I had an old stereo on which you could hear the local radio station coming out of the speakers... even if the stereo was unplugged. I had a CB radio once when I was a kid, and my voice would show up on tapes recorded on the VCR on the other end of the house. This sort of thing happens all the time.

"It would be much easier to buy a radio if you want to be able to change the channel."

LOL! Tom, you are absolutely right there! "much easier" is possibly the understatement of the year :))

Glue.. I have a nice AM radio.. I am happy to swap it for your Theremin if you want! ;)

To get rid of that radio reception, you'll need a couple of ferrite isolators on the power cord of the theremin. (but that don't allways work).