(under subclass 219) Subject matter including a device that transform a characteristic of a typical two level pulse or digital data signal into another form suitable for transmission over a transmission circuit.
(1) Note. An example of a modem is a device which converts two level pulse signals into two tone signals.
SEE OR SEARCH THIS CLASS, SUBCLASS:
257+, for cable systems and components.
SEE OR SEARCH CLASS
329, Demodulators, for demodulators only.
332, Modulators, for modulators, per se.
379, Telephonic Communications, 90.01+, where data is sent over lines specifically claimed as telephone lines.
395, Information Processing System Organization, subclasses 821 through 894 for transferring data from one or more peripherals to one or more computers or digital data processing systems for the latter to process, store, or further transfer or for transferring data from the computers or digital data processing systems to the peripherals.
709, Electrical Computers and Digital Data Processing Systems: Multiple Computer or Process Coordinating,
200+, for data transferring among multiple computer or
