1 Hz Active Filter (CB6721E)

This very low frequency circuit was found in a 1964 Electronic Design. Transistors may be modern equivalents. The filter is low pass type.

| Clique na imagem para ampliar |

Tri State Logic Probe (CB5888E)
This simple circuit is powered by the logic circuit itself. Components are still common, although...
Center Tap Simulation with Diodes (CB4140E)
In the figure we show how two diodes can be used to simulate the center tap of a push-pull driver step....
Voice Scrambler (CB4756E)
This voice scrambler circuit was obtained from an American 1990s documentation. Used operational...