AUSTRALIAN SHORTWAVE JOURNAL

AUSTRALIAN SHORTWAVE RADIO JOURNAL

FOLLOWERS

Saturday, January 29, 2011

Spectacular 7/9 MHz daytime propagation openng from Asia/Africa

Kuching 5603 km

Meyerton 10,339 km

Kajang (Kuala Lumpur) 6350 km

Tokyo 8144 km

Seychelles 9638 km

Sao Tome 14,066 km

Xian 8814 km

Ascension 14,514 km

Pyongyang 8738 km
I was fortunate in being able to witness an amazing daytime propagation
event on 7 MHz and 9 MHz on the afternoon of January 28, here in Melbourne,
from Asia and Africa.

Strong signals were apparent in our early afternoon, with propagation via
substantially daylight paths, via the specialized summer mode, which occurs
on unpredictable occasions during our summer months on very hot days.

My observations were made at one of my favourite field sites in the
Warrandyte State Park, using the little Eton E5 receiver and a few metres of
antenna tossed into the bush, 20 km from central Melbourne, and about 25
mins from my home here in the eastern suburb of Mont Albert.

This mode is characterised by sudden appearances of signals, building to
great strength within a few seconds, sometimes remaining audible for several
minutes ior longer, then vanishing.

This propagation is via complex modes, partly of which is caused by
reflection off the TOP side of Sporadic-E clouds, over Australia and the
Indian Ocean, with reduced minimal intermediate
ground reflection.

It's fascinating to observe the constantly changing propagation pattern,
which puts to rest the myth that darkness is necessary for long-distance
propagation on 7 and 9 MHz!

In past years, the Mode disappeared by early February, so there are still
chances for some further propagation excitement, with temperatures of over
40 degrees forecast across Australia for the next few days!

DISTANCES FROM MELBOURNE (Great Circle - shortpath)

Ascension 14,514 km
Sao Tome 14,066 km
Meyerton 10,339 km
Delhi 10,175 km
Beijing 8814 km
Pyongyang 8738 km
Kajang 6350 km
Kuching 5603 km

SOLAR ACTIVITY ON JANUARY 28

10.7 cm solar flux - 81
SSN - 22

This is the summary:

7215 S. AFRICA TWR-Meyerton, *0430 African languages (first appearance this
summer!)
7255 ASCENSION BBC English 0350
7270 MALAYSIA RTVM-Kuching, dialects network 0448
7290 INDONESIA RRI-Serui, 0335
7295 MALAYSIA RTVM-Kajang, carrying English Traxx-FM Network from Kuala
     Lumpur 0225
7415 ASCENSION BBC 0405 Swahili
7445 ASCENSION BBC 0355-0400* English
9430 ZAMBIA CVC *0400 English
9460 SEYCHELLES BBC 0300 English
9500 CHINA CNR1 Shijizhung 0305 Chinese
9530 VIETNAM VOV 0330 nat net
9540 SAO TOME VOA 0330 African langs
9570 CHINA CNR23 Geermu 0310 Chinese
9595 JAPAN R. Nikkei, Tokyo, 0310 Japanese
9610 SEYCHELLES BBC 0330 Swahili
9635 VIETNAM VOV 0300 nat net
9675 CHINA CNR1 Beijing 0320 Chinese
9685 CHINA CNT5 Beijing 0300 Chinese
9730 N. KOREA VOK 0300-0400* English
9750 MALAYSIA VOM-Kajang, carrier on 0353, into Malay 0400, mega-signal!
9835 MALAYSIA RTM-Kajang, Sarawak-FM feed, 0300 English
9850 VIETNAM VOV dialects network *0400
9870 INDIA AIR nat net 0315
9885 SA0 TOME VOA 0405 English
I would certainly welcome some feedback from you on these daytime propagation phenomena!
Regards from Melbourne!

Bob Padula

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