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Thursday, January 8, 2009

Propagation, Monitoring and Information

This is an edited extract from the latest ARRL Propagation Bulletin, January 8, 2009:

2008 was a year of very low solar activity. More than 40 percent of this year's ARRL propagation bulletins reported zero sunspots for their respective weeks. The average daily sunspot number for the year was 4.7; in 2007, it was 12.8. The yearly averages of daily sunspot numbers for 1999-2008 were 136.3, 173, 170.3, 176.6, 109.2, 68.6, 48.9, 26.1, 12.8 and 4.7.

Sunspot numbers for December 25-31 were 0, 0, 0, 0, 0, 0 and 0 with a mean of 0. The 10.7 cm flux was 69.3, 69.2, 9.4, 69.8, 69.8, 68.5 and 69.3 with a mean of 69.3. The estimated planetary A indices were 3, 1, 1, 2, 0, 1and 10 with a mean of 2.6. The estimated mid-latitude A indices were 2, 2,1, 1, 1, 1 and 8 with a mean of 2.3.

Two years ago we wrote, "This is the first bulletin of 2007, the year we'll likely see the end of sunspot Cycle 23, the beginning of Cycle 24, and the minima between cycles." One year ago in the first bulletin of 2008 we noted the same quote from the previous year, and wrote, "Now a year later we might say the same about 2008." This is probably still true for past year, because since early 2008, we saw Solar Cycle 24 spots, and what looks like a slow increase in activity toward the end of the year, although a week of sunspots at the end of December would have helped to sustain the upturn. (end)

There have been no sunspots visible since December 13, 2008.

This has resulted in continuing depression of Maximum Usable Frequencies and Optimum Working Frequencies for long-distance transmission over darkness or semi-darkness paths.

Despite the zero sunspot count, the ionosphere continues to supportl ong-distance propagation over darkness or semi-darkness paths on frequencies below about 12 MHz.

Here in Melbourne, there is excellent reliable shortpath (darkness zone) propagation on 6, 7, 9, and 11 MHz from Europe, Africa, Middle East and Asiain the period 1600 to past 2200.

Occupancy in the 7 MHz band is very high in this period. Very few channels are vacant in the 1800-2000 period - these are 7185, and a cluster in the extended-band spectrum including 7370 7405 7430 7440 7460 7470 7485 75007505 7515 7535 7545 7550 7555 7560 7575 7585 and 7600.

Now, some information...!

On 49 metres, a new extended band usage for the BBC is 5790, from Rampisham, carrying Russian 1700-2100, and audible here with super strength signals since early January.

The Voice of Croatia is now using 15360 from Kranji (Singapore) for its services to Australia/NZ, 0600-1000, from Jan 1. This is in parallel with Wertachtal on 11690 and 9470. Here in Melbourne, excellent propagation on 15360 for the full timespan, but not so reliable on 11690 and satisfactory on 9470.

DW new frequencies since Jan 1:
6040 Sines 0400-0430 Arabic
7145 Wooferton 1600-1700 Russian
7145 Dhabaya 2000-2100 Russian
9475 Dhabaya 1300-1600 German
9690 WOF 2000-2100 English
9775 Ascension 0000-0200 German
15275 Sines 1900-2100 various incl English

Vatican Radio introduced/deleted these frequencies on Jan 1:
6140 Chita 1315-1400 to ITU 49 (new)
12070 Novisibirsk 0200-0330 to ITU 41 (new)
13785 CANCELLED Khabarovsk 2355-0045 to ITU 43/44

VOICE OF MESOPOTAMIA (via Simferopol, Ukraine) Kurdish, new schedule from Jan 1:
5890 1900-2100
7540 1500-2100
11530 0500-1515

For the latest monitoring notes from Melbourne, listen to the weekly Australian DX Report audio shortwave news magazines, either on-line or on-air (WWCR Nashville Sundays 0300-0315 on 5070 and Mondays 1245-1300 on 15825) The WWCR release is also simulcast live as streaming audio from

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