Found in documentation from 1924, this receiver has several sets of coils. Power is supplied by several batteries and listening on high-impedance headphones.
We found this circuit in a 1970 publication by General Electric. The components can be changed...
This high-Q low-pass filter was found in the October 1990 issue of Radio Electronics magazine. The...
Generating a square signal (50% active cycle), this circuit was found in Siliconix documentation from...