Found in a 1980s documentation, this circuit uses as base a component of the era. The formula for determining the conversion is given next to the diagram.
This circuit is more elaborate than the previous one, employing an integrated amplifier circuit of the...
This circuit is from a 2005 Linear Technology application manual. The circuit uses a commercial...
Found in an American paper from the 90's, this circuit can be adjusted to pass frequencies above 30 to 300...