Owen is correct- and anyone operateing 10& 6
meters will tell you the same thing! Have
been on 6 for around 45 years now, an can attest
that "E" openings can occur ANYTIME, day, or nite!
And, the "E" layer is ionized , to a degree, 24
hours per day (There are more than a few running
"Scatter", with power levels of 100-1KW makeing
contacts, when the band(s) are literally closed ).
Es is the "bread and butter" of the VHF operator,
rangeing from 35-400 miles for super intense
openings, out to 1200, or so miles, when the band
is barely open. Figure stations (on scatter), from
Montana, New Mexico, Colorado, and Wyoming being
copied with NO major opening, into Reno, Nevada!
And, keep in mind, you also get Double hop, 2
adjacent (or more) layers , giveing you cross
country capabilities. One further thing: IF
you shea short E skip on a band (say 10 meters),
odds are great that 6 is open; Same for 6 meter
short skip, often means that 2 meters, or at least
F.M.Broadcasts (88-108 MHz) will be open!. F2
is associated with sunspots-Es seems to get worse
as sunspot activity increases!Might you find this
interesting? Jim NN7K

Owen Duffy wrote:

I don't really know much about sporadic E, have a vague idea what it is
and that's about all, but doesn't it assume that there is an E layer to
begin with? This was about 7:30 PM, sunset was around 4:45 PM, and the E
layer would have been pretty much gone along with the sun, wouldn't it?

Sporadic E does not depend on sunlight, it is one of the mysteries of
Es.

Owen
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