Radio atmospheric In the case of the ionospheric D-layer, it depends, in addition, on time of day, season, latitude, and the geomagnetic field in a complicated manner. VLF propagation within the Earth–ionosphere waveguide can be described by ray theory and by wave theory. When distances are less than about 500 km (depending on frequency), then ray theory is appropriate. The ground wave and the first hop (or sky) wave reflected at the ionospheric D layer interfere with each other. At distances greater than about 500 km, sky waves reflected several times at the ionosphere must be added. Therefore, mode theory is here
Waves Radio annual Scottish Week celebrations. Following the success of the initial broadcasts the station returned every summer, with the introduction of additional broadcasts made over the Christmas periods in 1994 and 1995. The station ceased broadcasting in July 1996 and was unable to transmit over the festive period due to the announcement of the full-time licence. After gaining a full-time licence, Waves Radio launched on 6 December 1997, from its current studios at Blackhouse Circle. Glenn Moir is the stations news editor, responsible for producing the daily local news bulletins. These are broadcast at 8.30am, 12.30pm and 5.30pm Monday - Friday.