🔍 Key Concepts

• Synchro (selsyn) transmitter and receiver operation in a rudder angle indicator system • Relationship between transmitter stator windings (R1-R2-R3) and indicator stator windings (R1-R2-R3) when wired together, as shown in figure C • How mechanical torque is produced when the electrical positions of transmitter and receiver do not match

💭 Think About

• Look at the wiring in part C: what is directly connected between the transmitter and each indicator, and what is only supplied with power? How does that affect what changes when the helm is moved? • If the transmitter coil set is rotated 30° clockwise, what happens to the pattern of voltages across its three windings, and how will that pattern affect the magnetic field in the receiver windings? • In a follow-up system, what happens to the receiver pointer when there is a difference in electrical position between transmitter and receiver fields?

✅ Before You Answer

• Verify that R1, R2, and R3 terminals of the transmitter go straight to the R1, R2, and R3 terminals of each receiver in the illustration. • Confirm that the receivers are not designed to change the magnitude of voltage (no transformer ratio shown), but instead to follow the phase/position of the transmitter field. • Remember that any misalignment between transmitter and receiver magnetic fields creates torque on the moving element until the positions match.