Operated directly from the power grid, this detector was found in an 80's RCA documentation. The sensor is an ionization chamber. The SCR triggers a warning siren.
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...