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Why do AM stations come in better at night?
As it turns out, the ionosphere reflects certain frequencies of radio waves. So the waves bounce between the ground and the ionosphere and make their way around the planet. You can pick up some radio stations better at night because the reflection characteristics of the ionosphere are better at night.
What is transduction in broadcasting?
Radio transmission is a way of sending messages using radio wave propagation. Before that can happen sound information must be converted into electrical form so that it can be transmitted using electromagnetic energy. The process of turning sound into this form so that it can be transmitted is called transduction.
Why do high frequency radio signals have shorter range?
For this reason, and also because more bandwidth is needed for many more users, urban police and fire departments generally rely on UHF around 450–470 MHz, or the “trunked” frequencies in the 800 MHz band. At really high frequencies (i.e., above 5–10 GHz in the “microwave” region) you have to consider atmospheric absorption.
What are the frequencies of the FRS channels?
FRS Frequencies 1 462.5625 2 462.5875 3 462.6125 4 462.6375 5 462.6625 6 462.6875 7 462.7125 8 467.5625 9 467.5875 10 467.6125
From a physics perspective, the fundamental reason for this is something called the bandwidth theorem (and also the Fourier limit, bandwidth limit, and even the Heisenberg uncertainty principle). In essence, it says that the bandwidth Δ ω of a pulse of signal and its duration Δ t are related:
How many frequency bands are there in the audio spectrum?
The audio spectrum range spans from 20 Hz to 20,000 Hz and can be effectively broken down into seven different frequency bands, with each band having a different impact on the total sound. The seven frequency bands are: