I have an AM station that I like to listen to. If it is sunny outside the station comes in clear. If it is nighttime or cloudy, I can't get reception. Anyone know the reason for this?
2007-02-14 07:07:53 · 6 answers · asked by SoundmanC 2 in Science & Mathematics ➔ Engineering
This is explainable if the station is some distance from you. At night, the ionosphere directs the radiation differently than during the day; during the day, you get a ground wave, but at night, the ground wave is reduced as more of the energy is reflected off the ionosphere to reach locations farther away (sky waves). Also, many stations broadcast at lesser power at night than during the day, as the sky waves at night can cause interference at greater distances.
2007-02-14 07:13:25 · answer #1 · answered by Anonymous · 1⤊ 0⤋
Long wave length radio-waves bounce off the ionosphere which is close to the earth during the day than at night. Since you can get better reception at some times than at other you are probably receiving a reflected signal. At night that reflected signal path is longer resulting in more path attenuation leading to a weaker received signal. Clouds might also cause some signal attenuation. There may be a more complicated explanation arising from a two path (direct and reflected) situation where during the day the two paths are in phase causing wave reinforcement giving a stronger signal. At night the longer reflected path might then be out of phase causing wave cancellation leading to a weaker signal.
2007-02-14 07:22:55 · answer #2 · answered by Anonymous · 0⤊ 0⤋
The FCC requires most AM stations to reduce their operating power after sunset.
This is to reduce interference with other stations on the same frequency, because AM signals "carry" much further at night when the ionosphere is stable, and at a slightly lower altitude.
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2007-02-14 10:08:46 · answer #3 · answered by tlbs101 7 · 1⤊ 0⤋
The other comments are good but if u know where the station u may be able to make a simple dipole antenna and if u draw a line through the antenna ,the station should be perpendicular to the center of your antenna .
2007-02-14 07:31:32 · answer #4 · answered by JOHNNIE B 7 · 0⤊ 0⤋
Twiddle the antenna.
This is what's called in Oz, a phur... a Phur... well, buggrit... a lie.
Every time a truck rolls past - interference. Every time you tune-in to AM and listen: same problem.
Do you have an in-line filter? Very cheap, given the circumstances?
Are you listening in mono?
Paul
2007-02-14 07:28:56 · answer #5 · answered by cwoodsp 2 · 0⤊ 0⤋
The clouds reduce or attenuate the signal.
2007-02-14 07:13:45 · answer #6 · answered by Fordman 7 · 0⤊ 0⤋