This circuit was found in a Popular Electronics documentation from the 90s. It is possible to switch the frequency of an oscillator by voltage. The circuit can act as a shield.
This circuit generates a rectangular signal whose frequency depends on the electrolytic...
This circuit was found in an old publicatio n from the year 1958. The circuit controls an external load by...
This circuit that converts very low currents into voltage was obtained in the 80's used component...