Search Results for: Magnetic resonance imaging apparatus
that were single-note oscillators operated by a two-octave piano keyboard. the "musical telegraph" used steel reeds whose oscillations were created by electromagnets and transmitted over a telegraph wire. gray also built a simple loudspeaker in later models consisting of a vibrating diaphragm in a magnetic
july , u.s. patent improvement in electric telegraph for transmitting musical tones, issued july , u.s. patent automatic circuit-breakers for electro-harmonic telegraphs, filed jan , , issued feb , u.s. patent electro-harmonic telegraph, filed jan , , issued feb , u.s. patent telephonic telegraph apparatus...
https://en.wikipedia.org/wiki/Elisha_Gray