AET Navigation Systems 2

Question 1

Which frequency range is allocated to VOR ground stations?

Accepted Answer

108.00–117.95 MHz

Answer

VOR stations operate in the VHF band from 108.00 to 117.95 MHz.

Question 2

How does a VOR receiver determine the aircraft's bearing from the station?

Accepted Answer

By comparing the phase of the 30 Hz reference and 30 Hz variable signals

Answer

Bearing equals the phase difference between the 30 Hz reference (FM on 9960 Hz subcarrier) and the 30 Hz variable (AM) signals.

Question 3

DME equipment operates in which frequency band?

Accepted Answer

962–1213 MHz

Answer

DME interrogations and replies use the UHF band between 962 and 1213 MHz.

Question 4

A localizer receiver detects a predominance of the 90 Hz modulation tone. Where is the aircraft relative to the course?

Accepted Answer

Left of course, fly right

Answer

On the approach, 90 Hz predominates left of centerline, so the CDI commands a fly-right.

Question 5

Glideslope transmitters operate in which band?

Accepted Answer

UHF 329.15–335.00 MHz

Answer

Glideslope frequencies are UHF, 329.15–335.00 MHz, and are paired with localizer frequencies.

AET - Avionics Electronic Technicians Practice Test