A tonewheel or tone wheel is a simple electromechanical apparatus used for generating electric musical notes in electromechanical organ instruments such as the Hammond organ and in telephony to generate audible signals such as ringing tone. It was developed by Thaddeus Cahill for the telharmonium c. 1896 and patented in 1897. It was reinvented around 1910 by Rudolph Goldschmidt for use in pre–vacuum-tube radio receivers as a beat frequency oscillator (BFO) to make continuous wave radiotelegraphy (Morse code) signals audible.
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- 👉 Thaddeus Cahill in the context of Tonewheel
- Thaddeus Cahill in the context of Telharmonium
Thaddeus Cahill in the context of Telharmonium
The Telharmonium (also known as the Dynamophone) was an early electrical organ, developed by Thaddeus Cahill c. 1896 and patented in 1897. The electrical signal from the Telharmonium was transmitted over wires; it was heard on the receiving end by means of "horn" speakers.
Like the later Hammond organ, the Telharmonium used tonewheels to generate musical sounds as electrical signals by additive synthesis. It is considered to be the first electromechanical musical instrument.
View the full Wikipedia page for Telharmonium