Wien Bridge
This Vienna bridge oscillator generates a sinusoidal signal whose frequency depends basically on C2 and C4. The circuit is from an Electronics Now from December 1993.
This powerful sound emitter used in defense to intimidate people was found in a 90s Popular...
The circuit shown in the figure triggers a relay when S1 is pressed, but this only in the absence of...
This small receiver for the medium wave range was found in Radio Electronics magazine from July...