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 circuit is suggested by the Optoelectronics Sourcebook by Texas Instruments when AC signals...
This circuit was found in 80's Popular Electronics. Transistors are commonly used. The...
When the power is turned on, the output of this circuit goes to the “1“ logic level by a time...