This stereo meter-indicator was found in the August 1971 issue of Radio Electronics magazine. The transistors are known types and BC548 equivalents can be used.
We found this circuit in English documentation for PCs from 1996. The ZN448 is a very uncommon...
This circuit is from a Fairchild digital clock module shown in the March 1977 issue of Radio...
This circuit is regulated by zener and provides a voltage of 9 V. The circuit is from a Radio...