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(meteorobs) Overdense or Es?

You wrote:
 >Some have
 >suggested that this was spordic E layer that I have
 >been observing.If this is spordic E layer then it
 >mimics identically radio meteors in the FM band

First guess would be Es, as this is the start of the peak season.
The Europeans have had Es openings every day for the past week, including a 
HUGE opening a few days ago.  See maps at http://www.vhfdxdot de/

However, I have been monitoring TV Ch 2-5 all week for Es, and have seen 
very little to none.  (One note here - I'm in KY, and, from the maps 
published over the years, I'm in the area that is right under much of the 
most intensely ionized Es clouds!  Even elevating the antenna still does no 
good on 144 MHz when they are this close.  So I could have missed something).

For meteors, they have been fair recently.  Reports indicate that there 
were a more overdense bursts than usual about a month ago, and heard 
several nice ones today.  Nothing exceptional, tho.

The ionization is at the same altitude, and thus, at a given frequency, 
appears the same, whether caused by Es or meteors.  Overlapping overdense 
bursts can sound exactly the same as weak Es.  Strong Es, and separated 
overdense bursts, sound very different.

There are several different causes of mid-latitude Es.  One of these is 
meteors (have had several Es openings on 50 MHz during Leonids, and during 
Perseids of a few years ago; biggest was said to have been the '46 
Giocobinies).  This morning on 50 MHz I had a trace of Es, enhanced tropo, 
with a number of good pings and bursts superimposed on the signals.

How hard it can be to tell the difference between Es and overdense bursts 
depends primarily on the frequency being used and the equipment.  There 
have been times when I was not sure for awhile (50 MHz), tho only once or 
twice have I been fooled on 144 MHz.  I don't monitor the FM BC band for 
this, but do monitor TV Ch 2-5 for Es.

There has also been a running argument recently about just where a 
background of overdense bursts leaves off and Es begins....Then, with 
field-aligned irregularities thrown in and a couple of other propagation 
mechanisms that are related to all this, it becomes fascinating!

What did you hear?
I dunno!
But hope I get to hear some of it!
Shelby, W8WN

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