Automatic direction finder
Mike Tooley, David F. Wyatt · 2024
Radio waves have directional characteristics as described in the early chapters of the book. This is the basis of the automatic direction finder (ADF), one of earliest forms of radio navigation that is still in use today. ADF is a short/medium range (200 nm) navigation system providing directional information. This chapter looks at the historical background to radio navigation, reviews some typical ADF hardware that is fitted to modern commercial transport aircraft, and concludes with some practical aspects associated with the operational use of ADF.