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Sunspots don't cause appreciable increase in RF background at any frequency at sea level. They cause lots more excitation of the ionosphere, so shortwave radio
by brians 10y ago
Sunspots don't cause appreciable increase in RF background at any frequency at sea level. They cause lots more excitation of the ionosphere, so shortwave radio signals bounce better and further, but nothing up in UHF.
But other phenomena correlated with sunspots do cause UHF interference, so while wrong on the details I generally believe the story.
- CamperBob2 10y agoBut other phenomena correlated with sunspots do cause UHF interference What would be some examples of such phenomena, bearing in mind that we're talking about very short-range wireless links in a band shared with primary military users? It's not as if conflicts in that band haven't arisen before: http://www.w5yi.org/ama_news_article.php?id=191l http://www.w5yi.org/ama_news_article.php?id=191l Another example: http://www.tdsupplies.com/articles/395_MHz_Military_Radio_Remote_Interference.html http://www.tdsupplies.com/articles/395_MHz_Military_Radio_Re...
- brians 10y agoX-ray flares, which get through the ionosphere and mess with VHF and UHF. The collapse of the magnetosphere on the night side following impact of a coronal mass ejection—which not only make a lot of VHF and UHF noise, they have enough power to just break a device.
- CamperBob2 10y agoIn 433 MHz line-of-sight comms? On the surface of the Earth? If that ever happens, you have much bigger problems than a malfunctioning garage door.