This blocking oscillator configuration was found in a 1964 American book. The circuit can be designed with modern transistors and the frequency depends on the transformer.
This amplifier uses a 1975 integrated circuit, which is uncommon today. The circuit has a gain of 30...
Using junction FETs, a configurable configuration is achieved for very low frequencies. FETs can...
This 2-terminal regulator was obtained from a 1990s National Semiconductor manual. The components admit...