The main feature of this circuit found in an old American publication is that it is powered by the very signal it converts. The transistors are of the time and can be replaced by current types.
Based on an LS3404 this circuit was found in the July 1990 issue of Radio Electronics magazine. |...
This circuit uses common components at the time of its publication in the 1980s. The circuit can be...
We found this circuit in an Argentine publication from the 70s. The coil can be made with 80 turns...