The Vostok I is a 555 oscillator circuit with a pair of touch-sensitive antennae that control the frequency of the oscillator. The entire contact theremin is housed in the lower half of a cigar box.
The only user control aside from the antennae is the power switch located on the control panel.
This small instrument was built around 2008/2009 along with a slew of other theremins and noise boxes. It’s design was heavily influenced by the simple and uncluttered control panel of the Vostok 1, the Russian spaceship responsible for taking Yuri Gagarin to space.
Power is supplied by a single 9V battery, and there are no provisions for audio output or volume control.
The 555 oscillator circuit is set up with a single fixed resistor, with the second variable resistor being replaced by the two antennae. Completing a circuit between the two antennae creates a pitch, which can be varied based on the amount of resistance present. This can be daisy-chained through multiple people, objects, or other conductive materials.