This is a summary of frequency occupancy across the time span 0300 to 0400 on February 3 2020, on 49 and 31 metres, represented by a flurry of Asian transmitters. This is an example of the Daytime Asian Propagation Mode, which occurs here in South Eastern Australia durong our summer months, marked by sudden appearances of signals from the Far East, East Africa and Pacific, on daylight paths.
Propagation was via Specialized Modes, where there is no intermediate ground reflection (hop), with signals hitting the top side of the E layer and Sporadic E (Es) clouds and continuing upwards to the F layer.
This Mode is complex, and cannot be reliably predicted – it occurs mainly during the Australian summer, characterised by sudden appearances of signals with little fading, which may remain audible for varying durations, extending from a few seconds to several minutes. The effect is remarkable, with strong signals often audible on frequencies as low as 6 MHz from local noon.
A technical treatment of this propagation mode may be found in the 2020 edition of the ARRL's Handbook for Radio Communications, Propagation of Radio Signals, Chapter 19. page 17.
This research was made at Westerfolds' Park, Templestowe, in Melbourne's Outer East, at the Porter Street picnic area, using the little Eton E5 receiver and two metres of random antenna tossed into a nearby bush!
Times denoted by # are those at which the signal became audible
7260 VANUATU domestic, from #0330
9545 SOLOMON ISLANDS domestic #0330
9560 MADAGASCAR NHK-Talata, Swahili #0335 to 0400*
9610 CHINA CNR8 Chinese #0325
9635 VIETNAM VOV domestic local langs #0300 to 0325*
9665 N. KOREA KCBS Korean #0300
9720 CHINA CNR2 #0310
9730 MYANMAR Yangon, domestic, Burmese #0315
9765 THAILAND VOA (Deewa) Udon, Pashto #0300
9835 MALAYSIA RTM domestic, rekey FM Malay #0320
9850 CHINA Qinghai PBS Xining, Tibetan #0300
9865 INDIA Hindi #0320
9920 TAIWAN SOH Chinese #0330
9970 TAIWAN SOH Chinese #0330
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