This source for 50 W amplifiers per channel was found in 1967 Delco documentation. Transistors are from that time, difficult to obtain today.
This circuit was obtained in an Electronics World of 1969. It is a crystal oscillator with a 100...
This circuit was found in an American 1980s documentation. The transistors admit equivalents and the...
Operating in the range of 1.5 to 15 kHz, this sinusoidal oscillator is based on a 741 operational. The...