In this interesting circuit from Popular Electronics, the output voltage is the square root of the input voltage. Equivalent operational amplifiers can be tried out.
This circuit is from a Popular Electronics from the 90s. The integrated circuit admits equivalents...
This circuit, which can act as a shield, was found in an American documentation from the 90s. The...
This circuit regulates the alternating voltage of a load at 100 V. The circuit is from Motorola,...