This circuit was found in a documentation of the 80s, having didactic purpose. For R1 values between 10k to 1M can be used. Transistors are general purpose types.
This basic circuit is from an old documentation. The relay must be 50 mA maximum and must have a...
In the figure we have a typical relaxation oscillator with a SIDAC as well as waveforms and...
This unit gain circuit has a very low output impedance. The circuit is of the Linear Databook of...