On 6/21/2018 1:03 PM, ANDY DURBIN wrote:
So what is the the magic set of circumstances that opens a 6 m path between AK and AZ?
It's important to understand how E-skip works. It's called "sporadic E" because it depends on sporadic activation of the layer for reasons that are not understood by me. Propagation from E-skip is often "spotlight" in nature, especially when more than one hop is involved. We can work "single hop" when the ionized cloud is roughly midway between us and the other station; for two or more hops, at least two ionized clouds must line up -- that is, ground to cloud one to ground to cloud two to ground. With double-hop Es, it's common to be able to work stations within a radius as small as 50 miles. And then one or both of clouds moves and a different radius is illuminated.
Yesterday, for example, from here near San Francisco, stations 50-100 miles E of me were working China, and stations in TX and OK were working JA. I heard none of it. But at various times, a single skip cloud provided a path down to San Diego and into XE, another into AZ, S NM, and S TX. That was all before noon. Eventually I started seeing the SE US -- AL, FL, SC, GA, NC. Toward evening, we started seeing (and working New England and the upper Midwest (8-land). And so on. VT was there for perhaps an hour, then gone. Same for RI. VE3 was there for about an hour.
After dinner, I returned to the shack to see a screen full of JA. It was roaring for at least an hour -- but around 10:20 PM local, it quickly faded.
A great place to see (and study) this is this map. It stays in my browser during Es season (roughly May to July in NA). Once in a while, click on the <MUF ES> all the way to the right above the map.
https://www.dxmaps.com/spots/mapg.php?Lan=&Frec=50&ML=&Map=NA&HF=&DXC=ING2&GL= 73, Jim K9YC ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected]
