Hi all grey line propagation...something I have developed an interesting but a few things I dont understand. I have had limited success inc a fantastic contact from UK to the USA on 160m...still excites me the thought of that one. But...been getting on the radio 30min before my published sunrise...on looking out of the window to my eastern horizon were I see the sunrise in the UK...at the time I see the sky is already starting to brighten quite a lot at that time but the sun is still below the horizon...as I say this is 30min before posted sunrise. So do I need to be on the air at sunrise as it already getting starting to get light or twilight which is 50mins before our sunrise... Hope I am make sense. Nick 2E0LPL
I try to be on the radio closer to the twilight time or even a few minutes earlier. During the Winter I work gray line often in the evenings and during the summer I tend to do more in the mornings. This is due to my work schedule and what fits the best for me. I have worked VK and ZL QRP on SSB from North Carolina on 40 and 20 meters during gray line so it can be a fun time.
These may be helpful. WORKING THE GRAY LINE https://www.qsl.net/w2vtm/grayline.html Working With The Gray Line http://www.astrosurf.com/luxorion/qsl-propa5.htm
If you will run 160 m WSPR for a couple of nights, the grey-line times will show up fairly definitively!
See here for grayline propagation versus low band sunrise/sunset enhancement: https://www.ng3k.com/misc/n4kgprop.html Tor N4OGW
from the article N4OGW linked to: Yes! Most definitely. I've been able to work the special event stations in Spain on 40 just before sunset here in AZ.
You can find best explain about greyline propagation in ON4UN book - https://www.arrl.org/shop/ON4UN-s-Low-Band-DXing Below Greyline map in real time:
Use it, and open a new world: http://www.voacap.com/hf/ Set the two markers, then hit band-by-band prediction.
GRAYLINE effects refer to locations along the terminator, encircling the globe along a Great Circle Route. The GRAYLINE provides a low loss path of varying width and duration depending on frequency. On the Low Bands these propagation openings only last for a few minutes. On 40 meters, you may only get 15-20 minutes (maximum). == When I received my new Elecraft K3, over a decade ago, I connected it to the 40 meter vertical that I was using, at that time. == It was early June afternoon in the Midwest USA. I called CQ on 40 meters for my first contact on the Elecraft K3. A station in Uganda replied (solid S9) ... nice First Contact on the K3. After a 5 minute QSO, we signed — as his signal strength was beginning to fade. Other stations tried to contact him, but failed. Looking at the Globe, and position of the terminator at that time, it was an obvious Gray-Line contact.
