This circuit was found in a 1960s Motorola documentation. Transistors are types of the time and can be replaced by modern equivalents.
This linear circuit was found in a 1965 Electronic Design. The transistors are from that time....
This filter was found in the May 1989 issue of Radio Electronics magazine. The components can be...
In the figure we have the way to make the connection of voltage regulators in series to obtain a...