What happens when...

...You touch the antenna while in use? Touch it with your hand,some medal,your cat? also does playing a guitar near it(within range) affect it any? And i am pretty sure that a radio would do something; right?

When you touch the pitch antenna then you get a really, really high note that just plays without any vibrato or anything. When you touch the volume antenna then the instrument goes silent.

I haven't been brave enough, or bored enough to fiddle around to see what magnets and things will do to my theremin. I love it too much.