This circuit was found in a Popular Electronics from the 90s. It is intended to power the filament of old radio valves in recovery works. It is indicated for tubes that use 5 V of filament.
This circuit is more sensitive than the previous one, in the sense that we can use weaker and more...
This 3-transistor timer was found in the January 1994 issue of Electronics Now magazine. The...
This circuit appears in other articles in this section, but it is very interesting. It is a...