This basic relay configuration was found in a July 1994 Electronics Now. The relay is supposed to be sensitive, and the times are changed by changing C1.
Found in a 1960 Sylvania manual, this circuit can be implemented with a modern equivalent...
This configuration, already presented in other points of this section and website, is of a...
We found this precise crystal oscillator for the 144 MHz band, depending on the crystal used. The...