(under subclass 2) Systems comprising at least one normally operative wave transmission line and a spare transmission line, and automatically operable means associated with the transmission lines for using the spare transmission line in place of the normally operative transmission line upon failure of the normally operative line.
(1) Note. Systems for automatically substituting a particular device or system for a normally operative device or system are in general classified with the particular device or system. For example, systems for substituting repeaters in a two way repeater system are classified in Class 379, Telephonic Communications, subclasses 338+ and systems for substituting for defective amplifier system or a part of an amplifier system (such as a vacuum tube) are classified with the amplifier systems in Class 330, Amplifiers, subclasses 84 and 124+.
SEE OR SEARCH THIS CLASS, SUBCLASS:
13, for resonator type breakdown discharge systems which control the transmission over a line.
100+, for branched circuits with nonautomatic transmission line switching.
262+, for transmission line elements, which may include switching devices.
SEE OR SEARCH CLASS 307, Electrical Transmission or Interconnection Systems, particularly
23, 39, 64+, and 80+ for miscellaneous electrical systems of distribution which involve automatic substitution of electrical load circuits or supply circuits.
331, Oscillators,
49, for plural oscillator systems wherein one oscillator may be substituted for another.
