The purpose of this circuit is to convert a short-lived pulse into a negative rectangular pulse. The circuit uses a unijunction that can be replaced by an equivalent such as 2N2646.
This circuit is from an old American publication from 1977. Transistor Q1 can be a TIP42 and Q2 a...
This soft start circuit was found in a 1965 General Electric documentation. The SCR and bridge...
We found this circuit in an English publication from the 1980s. The circuit uses current...