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Science (non-SETI) :
Any truth in it?
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Author | Message |
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Michael Watson Send message Joined: 7 Feb 08 Posts: 1383 Credit: 2,098,506 RAC: 5 |
A non-metallic object near an antenna can, under certain conditions, reflect a VHF or UHF signal to it, and so, enhance its strength. The most familiar instance of this is a person standing next to a VHF ( FM ) receiver with a short rod antenna. The person's movements can cause the signal to change strength. A wet roof might make for a more efficient reflector than a dry one. |
kittyman Send message Joined: 9 Jul 00 Posts: 51468 Credit: 1,018,363,574 RAC: 1,004 |
It could also be that the cooler, denser air is more conducive to the transmission of the signal from the tower to your location, so the received signal strength is higher. "Freedom is just Chaos, with better lighting." Alan Dean Foster |
Gary Charpentier Send message Joined: 25 Dec 00 Posts: 30608 Credit: 53,134,872 RAC: 32 |
It could also be that the cooler, denser air is more conducive to the transmission of the signal from the tower to your location, so the received signal strength is higher. Water is a signal attenuator. Possible that some interfering signal is less when wet (attenuated), hence a better experience. Also possible that the wet roof acts as a ground plane giving a better experience. You could test for that with a garden hose. Finally don't forget that in the winter, without a storm, the air is much dryer than in the summer. Check the relative humidity. Now today in the digital world, the signal should either be there, or not at all. No snow anymore, but blockies from bad jpeg decompression. Back in the analog days, I noticed that when a cold weather front passed here in Los Angeles the VHF San Diego stations became available, in the winter, and in the summer they were usually there but not always watching quality. More than you wanted to know: https://en.wikipedia.org/wiki/Radio_propagation http://www.dxfm.com/content/propagation.htm http://www.arrl.org/propagation-of-rf-signals |
Sarge Send message Joined: 25 Aug 99 Posts: 12273 Credit: 8,569,109 RAC: 79 |
It could also be that the cooler, denser air is more conducive to the transmission of the signal from the tower to your location, so the received signal strength is higher. 70s, Dad watching snowy MASH from 60 miles away. Hard to look at. But the theme song haunts. |
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