This 3-tube receiver is from a 1924 publication. The circuit has 3 supply voltages and a high-impedance headphone output.
This circuit was found in a 90s EDN. Its purpose is to increase the efficiency of operational...
This circuit is used to match a high impedance input source with a low impedance output device...
This is an improved version of the previous circuit also found in the December 1990 Radio...