Current HF fadeouts & Comms warnings

Shortwave listening. BBC World Service, Deutsche Welle etc

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floppy
Posts: 50
Joined: Sat Oct 30, 2010 12:15 pm
Scanners and Receivers: Sangean ATS 818CS
Location: WA

Current HF fadeouts & Comms warnings

Post by floppy » Thu Sep 08, 2011 11:13 am

There is currently a Comms & Fadeout warning for the HF bands
this is part of an email I got from IPS
Note:
An IPS MUF depression HF Warning and IPS shortwave fadeout HF Warning are both current. Shortwave fadeouts degrade lower shortwave radio frequencies first (through increased ionospheric absorption) and the usual strategy during shortwave fadeouts is to try a higher frequency. In contrast, during periods of ionospheric MUF depression, the upper frequencies are degraded first and the usual strategy is to use a lower frequency.

In general use a lower frequency if you are having trouble with your normal workable frequency.

If a shortwave fadeout occurs during a period when ionospheric MUFs are depressed the available HF bandwidth will be "squeezed", with increased absorption raising the lowest usable frequency and the ionospheric depression lowering the highest usable frequency. Under such conditions it is suggested that the HF communicator operates on the highest usable frequency, even though this may well be in fact lower than what is normally supported for that particular circuit.
thsi has been caused by some recent solar flares that reached X category
http://spaceweather.com/glossary/flareclasses.html

For those interested in HF Comms this page is worth keeping an eye on
http://www.ips.gov.au/Space_Weather

floppy

floppy
Posts: 50
Joined: Sat Oct 30, 2010 12:15 pm
Scanners and Receivers: Sangean ATS 818CS
Location: WA

Re: Current HF fadeouts & Comms warnings

Post by floppy » Thu Sep 08, 2011 3:45 pm

Tuesday in New Mexico, amateur radio astronomer Thomas Ashcraft recorded some Solar Noise at 21 MHz from this solar event and put it on the net, spaceweather.com put it up here so you can listen
http://spaceweather.com/images2011/07sep11/puffs.mp3
it is interesting to note that this noise will extend right up and down the RF Spectrum


floppy

floppy
Posts: 50
Joined: Sat Oct 30, 2010 12:15 pm
Scanners and Receivers: Sangean ATS 818CS
Location: WA

Re: Current HF fadeouts & Comms warnings

Post by floppy » Sat Sep 10, 2011 7:14 am

this report from Norway is interesting
http://spaceweather.com/submissions/lar ... 582815.jpg
as well as noting strong ground currents from the Geo-magnetic storm
you will also see the storm made significant radio noise at VLF frequencies of 23.4 kHz and 22.1 kHz


floppy

floppy
Posts: 50
Joined: Sat Oct 30, 2010 12:15 pm
Scanners and Receivers: Sangean ATS 818CS
Location: WA

Re: Current HF fadeouts & Comms warnings

Post by floppy » Sun Sep 25, 2011 3:58 pm

More Solar storms lately
for the Sept 25
http://spaceweather.com/
Active sunspot 1302 has turned the sun into a shortwave radio transmitter. Shock waves rippling from the sunspot's exploding magnetic canopy excite plasma oscillations in the sun's atmosphere. The result is bursts of static that may be heard in the loudspeakers of shortwave radios on Earth. Amateur radio astronomer Thomas Ashcraft recorded this sample from his backyard observatory in New Mexico on Sept. 24th:
"Saturday was a super-strong solar day with near continuous flaring and radio sweeps," says Ashcraft. "The sound file (above) corresponds to an M3 flare at 1918 UTC. It was the strongest radio sweep of the observing day."
"Try listening to the radio bursts in stereo," he advises. "I was recording on two separate radios at 21.1 MHz and 21.9 MHz, and I put each one into its own channel of the audio file. This gives a spatial dimension as the bursts sweep down in frequency."
the sound file is here
http://spaceweather.com/images2011/25se ... hcraft.mp3

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