A. BASIC SUBJECT MATTER OF CLASS
This is the generic class for modulators. A modulator is adevice which varies a characteristic of a repetitious electricalor electromagnetic wave of less than infrared frequency in accordancewith a characteristic of an arbitrarily varying information carryingsignal. Classification herein is broadly by the type of modulation exhibitedby the output signal.
B. COMBINATIONS WITH BASIC SUBJECT MATTER INCLUDED IN THISCLASS
1. A modulator combined with structure for measuring or indicatingsome aspect of the modulation process or characteristic of the modulatedsignal is classified here. Specifically, measurement or indicationof a frequency or amplitude modulator is classified here.
2. A modulator combined with a specific modulating signalsource (e.g., microphone or photocell) is classified here by modulationtype unless provided for elsewhere.
3. A modulator combined with structure to improve the modulationis classified here. Such structure might include, for example,a particular power supply for electronic devices within the modulatoror structure to correct for distortions in the modulated wave.
4. A combination including both a modulator and a demodulatoris classified here where such combination is not provided for elsewhere.
C. MISCELLANEOUS SYSTEMS AND DEVICES USED WITH MODULATORS
This class also provides for (a) miscellaneous systems anddevices which are not of general utility and which are limited touse with modulators and (b) miscellaneous systems and devices usefulwith modulators which are not otherwise classified. Examples ofsuch subject matter are a structure limited in use to measurementof a modulated wave, a multiplex modulator where a plurality ofmodulating signals are imposed on a carrier or pulse wave, or amodulation converter where modulated energy of one character isconverted to modulation energy of a different character (e.g., frequency modulationto amplitude modulation).