Hi Andy,
Ducting takes place over a relatively small area. Depends upon cloud layers and temperature zones This event took place ~ world wide. Band openings between North America to Asia, and Australia. 73 Bruce-k1fz http://www.qsl.net/k1fz/beverage_antenna.html On Mon, 6 Feb 2017 12:20:07 +0000 (GMT), Andy Cook wrote: I think you'll find this was Magnetospheric Ducting. Take a look at some of the articles here http://la3za.blogspot.co.uk/search/label/Unusual%20Propagation and here http://folk.uio.no/sverre/papers/2009_MagnetoDucting-QST-LA3ZA.pdf. Delay depends on your latitude - but couple of hundred millseconds is about right and this is a peak time of year for the effect. I've heard this quite frequently on 80m around mid local-evening during the winter, and one occasion - on 3rd Feb last year - very strongly indeed. That night I was able to hear my echoes with just 25mW into a dipole on 80m - but it's often strong enough to be audible with a few watts. I've read papers which suggested it does also occur on 160m. Reports of these being less strong / gone when you switch to a vertical look plausible as well since they apear to require vertical incidence from the ionosphere. 73, Andy, G4PIQ _________________ Topband Reflector Archives - http://www.contesting.com/_topband _________________ Topband Reflector Archives - http://www.contesting.com/_topband
