The reason why an amateur radio operator is called a 'ham' is not known. Some relate these three letters (HAM) to the names of three great radio experimenters. They are- Hertz (who practically demonstrated the existence of electromagnetic waves in 1888), Armstrong (who developed a resonant oscillator circuit for radio frequency work) and Marconi (the 1909 Nobel laureate in Physics, who in the year 1901 established the first transatlantic radio contact)