Transmitting magnetic compass operating principle

Transmitting magnetic compass operating principle

Conversion of magnetic compass into repeating compass.
Flux gate is mounted below the compass card.
Flux gate can detect magnetic field direction. (Position of the rotating compass card)
Flux gate will produce output signal.

Construction:
Flux gate consists of two thin wires of mumetal.
Each thin wire is placed inside a glass tube.
Each Glass tube is wound by a coil.
Two coils are placed parallel to each other.
AC is applied to produce opposite magnetic field in two coils.
The whole assembly is surrounded by a secondary coil C.
Secondary coil C will produce EMF.

TMC purposes:
Output signal can be used in autopilot.
Output signal can be used in other equipment.
Can be used where periscope is not available.
In a TMC, zero signal position-Null position can occur when the flux gate and compass magnet are 90 degree to each other.