This voice scrambling scrambler was published in the August 1982 issue of Radio Electronics magazine. The circuit is for old analog telephone lines.
This circuit was obtained from an American 80's documentation. The transistors can be 2N2222 and...
This low Power simple amplifier is intended to the use with high impedance phones. The circuit is...
This circuit was found in a 1963 magazine, but can still be easily assembled with some current...