Geri:

... are you looking for the explanation of the occasionally reported LDE's
(= long delayed echo)?


No, not an "explanation" a smaller project to make maybe one variant of
LDE's predictable or repeatable.  I have been into the LDE research for a
long time now and have made some progress.  I have found a way to positively
identify a signal, without direct reference to other signals, to identify a
given signal as being an LDE or NOT an LDE, that has made some of the work a
little easier.

There are at least several LDE mechanisms, once one gets beyond the ROW
(ROund the World) variants, say out to 2.2 seconds or so.  After that we get
into the serious time delays.  I have a large chirping facility here that I
am slowly bringing on line as a fully automatic transmitting facility.  The
progress is slow however.

I don't have the education to do the "explanation" part, my goal is very
modest - to put one peg in the ground in this area will be enough.  Despite
some 20 + years of being conscious to the issues, I have only heard directly
one LDE while operating on HF and then I did like so many I failed to
document the experience at the time.  I have trained myself out of that
problem should it happen again.

If your into this work contact me directly please, this reflector is not
likely interested in this subject.

Thanks and 73

Larry
VA3LK