This voice scrambling scrambler was published in the August 1982 issue of Radio Electronics magazine. The circuit is for old analog telephone lines.
What is a dual frequency generator for? There are several possibilities of use for this circuit. The...
The circuit, illustrated in the figure, consists of the direct application of the ULN2003 in which...
This circuit was found in a Popular Electronics from the 90's. The output signal can be applied to a...