“AVIATION RADIO DIRECTION FINDERS AND NON-DIRECTIONAL BEACONS: PRINCIPLES OF OPERATION AND THEIR IMPORTANCE IN AVIATION”, EJGMRE, vol. 2, no. 4, pp. 18–26, Apr. 2026, Accessed: Jul. 06, 2026. [Online]. Available: https://eurekaoa.com/index.php/9/article/view/792