I found tis circuit in na old documentation from 1958. The circuit uses germanium transistor availble that time and hard to obtain today. The circuit is indicated for phono applications using variable reluctance transducer.
This source was obtained from a former publication for valves but also serves for powering common...
In the figure we have the way to implement a power zener diode. The voltage depends on the zener,...
Two NAND gates are used in the configuration shown here to perform as a monostable triggered by...