3D60.u8 - Theremin
A working electrical instrument demonstrating resonant circuits and variable oscillators.
Connect the 1/4" plug to the PHONES output on the Theremin. Plug that into a Samson Amplifier. Port the output of the amplifier to a speaker. The u-shaped volume antenna must hang over the side of the table and be free of obstruction for at least 2 feet. Initially, when the theremin is turned on, a tone should begin to be heard. Place your left hand over the u-shaped antenna (volume antenna), this will decrease the volume. Use your right hand to interact with the vertical (pitch) antenna. This will change the pitch of the note produced by the variable oscillator within the instrument.
Place your left hand over the u-shaped (volume) antenna. Place your right hand parallel to the vertical (pitch) antenna. By moving your left hand up and down, the volume of the system will change. By moving your right hand left or right, the pitch of the note produced will change. Practice is needed to get the hang of how to play this instrument.
An instrument you play without touching! Each antenna has two oscillators - one fixed and one variable. Each hand acts as the ground plate of a capacitor - connected in parallel to the variable oscillator. The proximity of a hand to an antenna affects the frequency of a variable oscillator, and the difference in frequency between the two oscillators of either antenna determines the pitch or volume.