This different circuit was patented and described in the Radio Electronics magazine of March 1958. In that section it used to present different configurations that received patents.
The circuit shown in the figure generates a signal between 50 and 100 MHz and can therefore be...
We found this simple alarm circuit in a 1981 documentation. As we can see, it is a car alarm...
This simple timer with unijunction transistor was found in an old American technical...