A popular transmitter back in the day was based on the Hartley oscillator (PDF link). Using only a single triode tube and a tuned circuit with coils wound from 1/4″ copper tubing, Hartley ...

Let us apply our knowledge of oscillator fundamentals to some commonly used oscillator circuits. Figure 2-2( a) shows a popular circuit known as a Hartley oscillator. Its identifiable feature is the ...