[ARC5] LDE

[Dennis Monticelli]

Ken,

On what band did you experience this LDE?  I have heard LDE's on the strong
signals of local DX'ers on occasion.  The band was 20M.

LDE's occur in integer delays of approx 128ms as I recall (the time it
takes for a signal to circumnavigate the earth).  Yes, ducting is the
theory usually offered.

Dennis AE6C


On Thu, Jul 18, 2013 at 9:45 AM, Kenneth G. Gordon <kgordon2006 at frontier.com
> wrote:

> On 18 Jul 2013 at 7:37, Bruce Long wrote:
>
> > yes I think I heard one as well and there is scientific documentation-
> > not much but some- of the phenomona.
>
> The first one I experienced was VERY clearly an LDE. I was operating as
> NCS on PAN (a CW traffic net) back in the 1960s or 1970s sometime. I was
> operating full break-in with a KW rig I had then, a TechRad T-350-XM (wish
> I
> still had that rig).
>
> I began hearing a weaker signal between my sending and I thought it was
> someone trying to break me and join the net.
>
> The signal got stronger and stronger, and I finally figured out it was my
> own
> sending coming back to me with a significant delay
>
> The echo built up to a good 579. I tested it by sending "long dots", and
> listening for the reply, which was, at its shortest, about 1/2 second or
> so, as I
> remember it.
>
> It built up to a peak in loudness, then slowly faded out and finally
> disappeared.
>
> The time between my sending and the echo became longer and longer as it
> faded out.
>
> The length of time this LDE lasted was on the order of several minutes from
> when I first heard it to its final fade out.
>
> The second such incident which occurred to me was much less "impressive",
> only lasting a few seconds, and took place at least 25 years after the
> first
> one. I don't remember much about that one, except that it did occur.
>
> What little documentation I have read on these things never really
> satisfied
> me as to the explanation of the cause. "Ducting" was one.
>
> It is still a complete mystery to me.
>
> Ken W7EKB
> ______________________________________________________________
> ARC5 mailing list
> Home: http://mailman.qth.net/mailman/listinfo/arc5
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:ARC5 at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>