Third Order Low Pass Filter (CB25264E)

This circuit was found in the December 1990 issue of Radio Electronics magazine. It was used in a home theater sound system.

CMOS Intermittent Siren (CB19231E)
This circuit generates a pulsed tone whose frequency depends on C2 and whose flashing depends on...
Audio Q Multiplier (CB20642E)
This circuit of a Popular Electronics from the 80's selects tones around 60 Hz, acting as a filter...
Overload sampler (CB8354E)
This circuit samples the current in a load and in case of excessive value it activates a...