Found in a 1947 publication, this 7-tube amplifier uses four tubes in the output stage. The circuit uses a power source with a transformer.
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...