With this circuit it is possible to tune an AM signal using a 5k potentiometer (4k7). The circuit was found in a publication from the 1980s and the PLL can be replaced by an equivalent one, with tests.
This circuit was obtained from a 1966 documentation. The transistors are of the time. The circuit...
This precision rectifier circuit is suitable for applications in an AC / DC converter. We find it...
I found this circuit in a Popular Electronics from November 1999. The magazine is no longer...