Propagation into Melbourne

Spectrum research here in Melbourne has revealed that long distance
propagation has now appeared in the noon window, in the period 0100 to 0300,
on 6 MHz.

This heralds the arrival of the winter daytime propagation mode, an annual
occurrence, which offers marvellous opportunities for studying propagation
on these band during the present period of very low solar activity.

A preliminary examination of spectrum occupancy on 6 MHz on May 27
revealed shortpath propagation from Europe, Middle East, and Africa, and
longpath from the Americas in the period 0100 to 0145 (11 am to 11.45 am).

At about 0200 (noon), longpath from Europe, Middle East and Africa, and
shortpath from the Americas had become the dominant mode, which continued
throughout our afternoon.

This pattern will be sustained during our winter months, up to the end of
July.

At noon in Melbourne, on May 26, the sun's azimuth at noon was down to 30.2
degrees. The lowest noon azimuth will be 28.8 degrees on 17 to 26 June.

Solar transit on May 26 in Melbourne was 0217 (2.17pm)

Our latest sunrise occurs on June 28 to June 30, at 2137 (7.37 am) and pit
earliest sunset will be on June 9 to June 17 at 0707 (5.07 pm).

These factors significantly influence HF propagation during our daytime
period in our winter months on 5 MHz to 12 MHz.

The Appendices summarize trans-noon spectrum occupancies on May 26, 2010.

5920 SWEDEN RCI via Horby, Arabic 0245 (***NEW RELAY FOR A10***)
5925 GERMANY RL-Lampertheim Russian
5930 SLOVAK REP. R. Slovakia International, French 0225
5960 CANADA NHK-Sackville English 0300
6020 ALBANIA CRI via Cerrick, Mandarin 0200
6030 USA R. Marti Greenville 0300
6055 SPAIN REE Spanish 0225
6100 FRENCH GUYANA WYFR via Montsinery, English 0200
6105 GERMANY RL-Wertachtal Belarusian 0105
6125 SPAIN REE Spanish 0225
6175 CANADA V. of Vietnam via Sackville, English 0100
6200 BULGARIA R. Sofia Russian 0305

7220 IRAN VOIRI Armenian *0300
7245 IRAN VOIRI English *0130
7270 ARMENIA VOR via Yerevan, Russian 0000 to 0400
7280 GERMANY IBB Wertachtal 0130
7285 MOLDOVA VOR via Grigoripol, Russian 0000 to 0400
7305 VATICAN VR SMG Spanish 0200
7310 GERMANY VOA Wertachtal Amharic *0300
7315 ISA WHRI English 0200
7335 VATICAN SMG var langs 0100-0200
7355 USA WRNO Spanish 0100
7365 USA R. Marti Greenville 0100
7385 ROMANIA RRI French 0100-0200
7390 GERMANY RL Lampertheim Tatar-Bashkir 0300
7400 BULGARIA R. Sofia 0200-0300
7425 ALBANIA R. Tirana English 0230
7475 GREECE VOG Greek 0130-0400

The window 0430 to 0500

Spectrum occupancy sampled on May 27, 2010:

5810 USA WEWN Spanish
5925 GERMANY RL-Lampertheim Russian
5970 CUBA RHC English
6115 ENGLAND BBC Skelton Arabic
6130 LITHUANIA NHK via Sitkumanai *0430 Russian (***NEW RELAY FOR A10***)
6140 ROMANIA RRI Romanian
6145 S. AFRICA BBC Meyerton Portuguese
6180 PORTUGAL DW Sines English
6185 VATICAN VR SMG various
6200 BULGARIA R. Sofia Bulgarian

7210 ETHIOPIA V. of Broad Masses Tigrinya
7240 RWANDA DW Kigali English
7280 GERMANY R. Farda Wertachtal Farsi
7325 ENGLAND BBC Rampisham Arabic
7350 IRAN VOIRI Arabic
7435 GERMANY RL-Biblis Russian