This circuit was found in a 90s EDN. Its purpose is to increase the efficiency of operational amplifiers. Power MOSFETs and inverted zeners support equivalents.
This circuit was adapted from an Italian publication that no longer exists. This is “Onda Quadra”...
This circuit uses only passive components and must be tuned to the operating range. The circuit is...
This oscillator with crystal for overtone operation was found in an old American documentation. The coil...