Thanks for checking the voltage to the preamp. If you have a problem again, check to see if the LED on the power inserter is still ON. as it should be, or OFF.
Thanks for the tvfool signal report.
http://www.tvfool.com/?option=com_wr...e6a4c5db6f4ec6
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NBC, ABC, PBS always come in fine. CBS is normally fine, but if the antenna isn't aimed exactly it can be dicey, depending on the weather.
I only get FOX from around September/October until April/May.
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That description exactly matches your signal report. NBC, ABC, and PBS are your strongest signals, and CBS is listed just a little weaker than PBS. Fox is a lot weaker than CBS.
CBS sends 992 kW out of 1000 kW ERP in your direction. If you click on the CBS callsign in your report, this is what you will see:
http://www.tvfool.com/?option=com_wr...dALLTV%26n%3d4
Fox is much weaker because it has a very directional transmitting antenna that sends only 11 kW out of 320 kW ERP.
http://www.tvfool.com/?option=com_wr...dALLTV%26n%3d5
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I only get FOX from around September/October until April/May. It is like this every year, and was the same even before 2009 when it was analog. I assume it has something to do with the atmospheric changes as the seasons change. It does not correspond with the leaves being on or off the trees.
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What you assume is correct; the seasonal change does make a difference. In the warmer weather, the Fox signal is not able to bend down to your location by refraction because the density of the air changes in warm weather.
Forum member
tripelo says it much better than I can:
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Originally Posted by tripelo
Daytime Signal Fade (Independent of Multipath)
Gradual bending allows radio signals to somewhat follow the earth’s curvature for some distance beyond normal line-of-sight. This gradual bending is somewhat independent of phenomenon like ‘tropo scatter’. As you know, long distance TV signals can fade (reduce in strength) in daylight hours. This can be due to smaller temperature gradients that result when the sun uniformly heats the air in the lower atmosphere during much of daytime hours. Smaller temperature gradients result in less bending of the signals back towards the surface, thus the daytime fade.
Note: Temperature is not the end cause of the bending of RF signals. Temperature is a measure of one particular driving factor (thermal energy) that can decrease atmospheric density, thus affecting the density of everything contained in the atmosphere (water vapor, etc).
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