This basic CMOS 4001 circuit was found in the April 1976 issue of Radio Electronics magazine. The circuit generates rectangular signals, and the components can be changed to obtain other frequencies.
This line protector circuit was found in a 2002 documentation, but it is totally current and...
This antenna for the frequencies 146 or 440 MHz was found in a magazine 73 for Amateur Radio of...
With this circuit it is possible to increase the output voltage of a 7812 regulator. The circuit...