Noise figure converter
Convert noise figure to noise temperature and back — the two ways of saying how much hiss a receiver adds.
That's about the same as a satellite receiver. That is an equivalent noise temperature of about 75.09 K.
What it means
How quiet is that receiver?
Everything here is referred to 290 K, the standard reference temperature. A receiver pointed at cold sky sees far less noise than one pointed at the ground.
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Your noise in every unit
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Three things worth knowing
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1 dB noise figure = 75 K
And 3 dB is 290 K, the reference temperature itself. Below 1 dB the temperature scale resolves differences the decibel scale hides.
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The first stage decides
Friis showed that the first amplifier in a chain dominates the total noise, because everything after it is working on an already amplified signal. That is why the low-noise amplifier goes at the antenna.
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Noise figure is not gain
A 30 dB amplifier with a 6 dB noise figure is worse than a 12 dB amplifier with a 0.5 dB figure. Amplifying noise along with the signal gains you nothing.
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Background
About noise figure
Every amplifier adds noise of its own. The noise figure says how many decibels worse the signal-to-noise ratio is after passing through it.
Satellite and radio astronomy work prefers noise temperature: the temperature a resistor would need to be to make that much noise on its own. A 1 dB noise figure is 75 K.