This circuit was found in a Popular Electronics from the 90s. The transistors are general purpose, and the gain depends on the ratio between R2 and R1.
Short square pulses trigger this damped oscillator. The frequency of the damped oscillations is...
Based on common components, this circuit was found in an English publication. The circuit is...
This circuit is from a 1977 publication for radio amateurs presenting a crowbar protection. The...