Current HF fadeouts & Comms warnings
Posted: 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
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
this is part of an email I got from IPS
thsi has been caused by some recent solar flares that reached X categoryNote:
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.
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