This circuit is from an old American documentation from the 70s. Transistor 2N3904 can be replaced by BC548. The relay must have 100 mA of maximum current.
In the figure we have a practical circuit for use with a magnetic transducer. The 20 M ohms...
Based on the well-known LM3909, this LED pulser circuit was found in American documentation from...
This circuit was found in old documentation but uses components that are still common. The circuit...