This simple logic test circuit with 3 LEDs was found in October 1985 Radio Electronics magazine. The power supply is according to the logic, and this version is indicated for TTL.
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...