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Why does WWVB coverage vary by time of day?
I just got a watch that syncs to WWVB time signals, and was researching it. I discovered that there are times when it is 'available' in my area and times when it isn't. Here is an example:
http://www.ntp-time-server.com/images/WWVB_coverag...
I'm North of Toronto.
If you don't want to write out a description, a website that explains would be awesome.
Thank you!
The NIST site gives the coverage area, but doesn't explain why it is affected. That's what I seek to know. And I know that it will be long and complicated-that's why I would love to get a link. I've tried Googling it in every way I can think of, but to no avail.
The NIST site gives the coverage area, but doesn't explain why it is affected. That's what I seek to know. And I know that it will be long and complicated-that's why I would love to get a link. I've tried Googling it in every way I can think of, but to no avail.
2 Answers
- classicsatLv 78 years agoFavorite Answer
It all has to do with the ionosphere, and how the sun affects it. At different solar charge states it reflects, absorbs, or passes certain HF and lower frequencies, and depending on height of particular ionospheric layers, what angle they reflect.
Just search the web for Ionospheric propogation.
- ?Lv 78 years ago
The NIST site should explain it; otherwise, request a set of their publications.
Radio signal propagation is a subject requiring a lot of explanation,
especially because different frequency ranges are affected differently.
