HFU HF Underground

General Category => General Radio Discussion => Topic started by: ChrisSmolinski on February 14, 2012, 2228 UTC

Title: Unusual propagation today?
Post by: ChrisSmolinski on February 14, 2012, 2228 UTC

While looking at the signal levels of 7850 kHz today, from CHU, I noticed that there seemed to be a larger than usual daytime dip in levels, around 1600-1900 UTC:
http://www.hfunderground.com/propagation/chart.php?f=7850 (http://www.hfunderground.com/propagation/chart.php?f=7850)

Likewise, 3330 CHU also showed this: http://www.hfunderground.com/propagation/chart.php?f=3330 (http://www.hfunderground.com/propagation/chart.php?f=3330)

OTOH, 14670 kHz CHU showed a substantial increase in signal levels: http://www.hfunderground.com/propagation/chart.php?f=14670 (http://www.hfunderground.com/propagation/chart.php?f=14670)

However, WWV didn't show anything out of the ordinary, on either 15000: http://www.hfunderground.com/propagation/chart.php?f=15000 (http://www.hfunderground.com/propagation/chart.php?f=15000) or 20000: http://www.hfunderground.com/propagation/chart.php?f=20000

It's difficult to tell with 10000 kHz, as the signal level varies a lot with both WWV and WWVH audible at times: http://www.hfunderground.com/propagation/chart.php?f=10000 (http://www.hfunderground.com/propagation/chart.php?f=10000)

New York and Gander radio on 10051 kHz had some dropouts during that time period, but mostly a normal signal level. Curiously they did not fade out last night, as they usually do: http://www.hfunderground.com/propagation/chart.php?f=10051 (http://www.hfunderground.com/propagation/chart.php?f=10051)

The x-ray background flux was unremarkable today: (http://www.swpc.noaa.gov/rt_plots/Xray.gif)

Anyone else notice odd propagation today?

Title: Re: Unusual propagation today?
Post by: Zoidberg on February 16, 2012, 1212 UTC

I wasn't listening on the 14th, but conditions have been extraordinarily poor here the past day.  At the moment (1200z, 2/16/12) none of the CHU frequencies is audible and of the WWV freqs only 5 MHz is audible - and that just barely.  That's very unusual here.  The various aviation and maritime weather freqs I check are also barely audible.  Same with the 75-80m hams - the usual fellows with usually booming signals were barely audible overnight.

AFN on 5446.5 and 7811 are a little worse than usual.

Tuning around, only Radio Australia on 9580 and 9590 sound about normal.

Title: Re: Unusual propagation today?
Post by: cmradio on February 17, 2012, 1136 UTC

Quote from: Lex on February 16, 2012, 1212 UTC

I wasn't listening on the 14th, but conditions have been extraordinarily poor here the past day.

Same here on the west coast - the band around 1200z yesterday was so dead, I couldn't even hear the normal morning 3715 KHz crowd, which usually come in like gangbusters ???

No WWV and no CHU.

An Alaska plane enroute calling SanFran on 5574 was reporting "no contact" and said they had to relay via YVR on VHF.

Peace!

Title: Re: Unusual propagation today?
Post by: cmradio on February 17, 2012, 1222 UTC

Think I have the answer :)

http://www.sott.net/articles/show/241581-Not-Fully-Understood-Disturbance-Rippled-Through-Earth-s-Magnetic-Field

(site found on a Google, definately NOT my type of thing)

Peace!

Title: Re: Unusual propagation today?
Post by: ChrisSmolinski on February 17, 2012, 1319 UTC

Quote from: cmradio on February 17, 2012, 1222 UTC

Think I have the answer :)

http://www.sott.net/articles/show/241581-Not-Fully-Understood-Disturbance-Rippled-Through-Earth-s-Magnetic-Field
Peace!

Very interesting! I re-checked my graphs, and the times do seem to coincide. Good find!

Title: Re: Unusual propagation today?
Post by: hammarhead on February 17, 2012, 1606 UTC

Whatever the reason I wish it would stop. Bands have been low in general lately and it just plain sucks!!! At least it isn't snowing.