Theremin Synthesiser Kit for String Instruments (Mk3 01/18)Ref: Silicon Chip Magazine January 2018 Originally invented in 1919 using valve technology, and as featured on the soundtrack for the 1951 film "The Day the Earth Stood Still", the all "new" completely transistorised Theremin will give you a truly retro sound. This new model is easier to build than ever with the volume plate incorporated into the circuit board. Also, most components, the switch, the pot and the power socket are mounted on the circuit