This interesting 1924 triode tube receiver was found in a documentation by Gernsback. Observe supply voltages. Coils are for tuned wavebands.
Twin-T oscillator are designed to produce sine low frequency signals. These oscillator are...
Found in na 1970 EDN this circuit has a parallel regulation providing a symmetrical output of 15 V....
This circuit was found in an Electronic Design. It makes use of a relaxation oscillator to trigger...