Domanda 43, Radio Navigation - ATPL - Airline Transport Pilot license

The transmitter changes the frequency of the variable signal by 30 Hz either side of the allocated frequency each time it rotates
The transmitter varies the amplitude of the variable signal by 30 Hz each time it rotates
The receiver adds 30 Hz to the variable signal before combining it with the reference signal
The rotation of the variable signal at a rate of 30 times per second gives it the characteristics of a 30 Hz amplitude modulation