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Since 10 meters can frequently open up to propagate globally, most 10-meter repeaters use a CTCSS sub-audible access tone. 16 kHz-wide signals with 5 kHz deviation is normal in this band. 8 kHz-wide signals with 2.5 kHz deviation can also be found. 2.5kHz deviation is mandated by FCC rules below 29.0 MHz.
Frequency deviation is used in FM radio to describe the difference between the minimum or maximum extent of a frequency modulated signal, and the nominal center or carrier frequency. The term is sometimes mistakenly used as synonymous with frequency drift , which is an unintended offset of an oscillator from its nominal frequency.
Shortwave bands are frequency allocations for use within the shortwave radio spectrum (the upper medium frequency [MF] band and all of the high frequency [HF] band). Radio waves in these frequency ranges can be used for very long distance (transcontinental) communication because they can reflect off layers of charged particles in the ionosphere and return to Earth beyond the horizon, a ...
Sound pressure or acoustic pressure is the local pressure deviation from the ambient (average or equilibrium) atmospheric pressure, caused by a sound wave. In air, sound pressure can be measured using a microphone , and in water with a hydrophone .
is the peak frequency deviation; is the highest frequency in the modulating signal. For example, a typical VHF/UHF two-way radio signal using FM mode, [2] with 5 kHz peak deviation, and a maximum audio frequency of 3 kHz, would require an approximate bandwidth of 2 × (5 kHz + 3 kHz) = 16 kHz.
where is the signal mean or expected value and is the standard deviation of the noise, or an estimate thereof. [ note 2 ] Notice that such an alternative definition is only useful for variables that are always non-negative (such as photon counts and luminance ), and it is only an approximation since E [ X 2 ] = σ 2 + μ 2 {\displaystyle ...
Research shows that fasting for five to 20 days can lead to weight loss of two to 10 percent. But about two-thirds of the weight lost is lean mass, rather than fat mass.
In telecommunications, the free-space path loss (FSPL) (also known as free-space loss, FSL) is the attenuation of radio energy between the feedpoints of two antennas that results from the combination of the receiving antenna's capture area plus the obstacle-free, line-of-sight (LoS) path through free space (usually air). [1]