HFU HF Underground
General Category => General Radio Discussion => Topic started by: ChrisSmolinski on April 13, 2014, 1621 UTC
-
I've added this page to the HFU, which estimates the skip zone around a transmitter site for 6925 kHz, based on ionosonde data from Wallops Island, VA: http://hfunderground.com/propagation/nvis6925.html
There is also a link on the same page for estimates based off data from Boulder, CO.
The basics on how this is calculated is here: http://www.radiohobbyist.org/blog/?cat=12&paged=3
If you look at the graph for the estimates for yesterday (before the data scrolls off the left side), you'll see that the skip zone never disappeared. That's quite unusual for 43 meters, usually it does once the Sun is up and the ionosphere strengthens. Everyone I was in touch with online yesterday complained about how bad propagation was.
This data could be useful for listeners to see whether or not they're likely to hear relatively close stations. Likewise for operators in the reverse direction :-)
-
Even the Cubans on 49 meters were barely audible last night. Things didn't improve until you dialed down to 60 meters.
Interestingly, the AM'er's on 75/80 were raving about the great conditions down there.
-
Yeah, it as certainly a strange day for propagation.
I've added a display of the current foF2 value on the page. It serves as a general indicator of the strength of the ionosphere in this area.
There used to be a west coast ionosonde (Dixon CA I think) but it doesn't seem to be active. If I can find one, I'll add it to the page as well.
-
Yes, please!