you'l have to look it up but somewhere, somebody, with an airport has an ol fashioned range. Where you listen to know if your on the beam.
You are on the right "track". The A and N were radio signals transmitted by a low frequency station. When you crossed or stayed on the area where the N and A came together, you heard a constant, steady signal, which was called a "leg". When you arrived at the radio beacon and crossed it, you would pass over the "cone" of silence and you knew by your charts, where you were. There were low freq ranges all over the U.S. and some forgien countries. Both military and commercial airliners and general aviation aircraft would use these to navigate from point to point. This was accomplished by the pilot by listening in his or her head sets for the signal. To verify that you were going to the station, you would turn your radio down until you could barely hear the signal. If the signal grew as you flew, you were going toward the station, if it disappeared, you were going away. This was called a range orientation maneuver. When you arrived at your destination airport, you consulted your chart for heading to the airport, unless, as in many cases, the transmitter was located on the airport. Of course, these were "non-precision approaches and were nerve racking to say the least, especially in bad weather such as very low ceilings or thunderstorms. The Bombers and fighters during WW2 also used these navigational aids in returning to base after missions.
To shoot approaches to the airport of intended landing, you would first maneuver to pass over the beacon on a heading which was 180 degrees from the direction of the runway in which you intended to land. Example: Cleared to land, runway 27, Atlanta International airport, you would fly a heading of 090 degrees until you passed over the "cone" of silence, then, after determining which speed at which you wanted to work the procedure, 180 knots= 3 miles per minute, 120 knots= 2 miles per minute. Back in those days, 120 knots was the common speed at which to work the procedure. After crossing the "cone" of silence on a heading of 090, you would time, by watch or clock on instrument panel, for 3 to 5 minutes, then you would do a procedure turn by turning right 45 degrees to 135, fly 2 min, then a turn back to a heading of 270 degrees, using a standard rate turn, and with no wind, you should be headed inbound to the airport and you could start descending for landing. If you descended to minimum decent altitude as dictated by your approach chart and you couldn't see the runway or airport, you would then execute a "missed approach", climbing straight ahead to a specified altitude, then start all over again.
When ADF indicator instruments came into use in late 30's and 40's, it really simplified the navigational system, but that is a subject for another thread!
