Map of monitored channels

This map shows the location of the monitored VLF transmitters (). The transmitters are from 760km (470 miles) to 5300km (3300 miles) from the receiving station. The azimuthal equidistant projection used for this map renders the signal paths – that follow great circles – as straight lines.
The icon denotes the location of the subreflective point(s) for each signal path. From one to three points exist depending on the transmitting station distance. They indicate where the signal sky wave bounces off the ionosphere.
Finally, the receiving antenna patterns are shown as blue (North-South loop) and red (East-West loop) dotted lines.

Note: The background map was generated with the Azimuth program written by VE6YP.