Hello Andy,

I use the tool at the botttom of this page:

http://www.classaxe.com/dx/ndb/reu/tools

My locator is JO11tm and that gives sunrise at 06:14 UTC and start 
of the twilight (grey line, my guess) zone at 05:40 UTC.

I have attached a screenshot that clearly shows the effect of 
pre-dawn enhancement, whilst Joe's signal disappears rather quickly 
after sunrise.

There is a seasonal effect on this type of enhancement.
I have yet to see an after sunrise enhancement in summer, whilst 
this is common in mid-winter.

Markus, I am living 8 km from the coast and this location is 
excellent for T/A reception. Reception from the (south) east is far 
more problematic!

73,
Roelof, pa0rdt

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