(under subclass 690) Subject matter in which the transmitter is of the same or similar structure as its self-synchronous receiver motor.
(1) Note. Systems classified herein are not to be confused with synchro transformer systems found in subclass 654, supra. A synchro transformer is an angular position pickoff device which cannot develop torque as can self-synchronous motor systems.
(2) Note. The transmitter and receiver windings of the systems in this subclass are some times called "selsyn" devices.
(3) Note. The following is an illustrative example:
[figure]
SEE OR SEARCH THIS CLASS, SUBCLASS:
654+, for synchro-transformer systems, see (1) Note above. SEE OR SEARCH CLASS
336, Inductor Devices, appropriate subclasses for the structure of transformers and inductive reactors.
