This 8-tube amplifier with 12 W output was found in an American publication from 1947. The output is in counterphase with pentode tubes.
This circuit, with adjusted sensitivity, can use common general-purpose transistors. The circuit is...
This circuit was found in a 1967 RCA documentation. The semiconductor components are from the...
This is the traditional configuration of na Astable Multivibrator using two NPN ttransistor....