(under the class definition) Subject matter wherein the amplifying device includes electrodes in a gas or vapor medium and which device depends upon ionization of a gas or vapor for its operation.
SEE OR SEARCH CLASS
313, Electric Lamp and Discharge Devices, appropriate subclasses, particularly
161, 163, and 567+ for gas or vapor tubes, per se.
315, Electric Lamp and Discharge Devices: Systems, appropriate subclasses, for circuits including gas or vapor tubes as the ultimate load device.
327, Miscellaneous Active Electrical Nonlinear Devices, Circuits, and Systems, appropriate subclasses for miscellaneous electronic tube circuits including gas or vapor tubes with a control electrode, controlled in operation.
