This circuit takes advantage of the hysteresis of a relay to provide a latching effect. The circuit acts as a trigger and the components must be according to the used relay.
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...