A SYNCHRO ROTOR is composed of either a single coil of wire wound on a laminated core or a
group of coils wound in slots in a laminated core. The laminated core is rigidly mounted on a shaft that is
free to turn inside the stator. Two slip rings are mounted on one end of the shaft to supply excitation
voltage to the rotor. There are two common types of synchro rotors - the salient-pole rotor and the drum
or wound rotor.
The SALIENT-POLE ROTOR has a single coil of wire wound on a laminated core, shaped like a
dumbbell or the letter "H." This type of rotor is frequently used in transmitters and receivers.
The DRUM OR WOUND ROTOR may be wound continuously with a single length of wire or
may have a group of coils connected in series. This type of rotor is used in most synchro control