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there is what is called flicker noise, or
1
// noise because it is inversely
proportional to frequency.
The noisiness of a device or stage, or even of a whole amplifier or
receiver, is specified as its noise factor or noise figure, which is
defined in various ways, of which a simple one is
It is usually expressed in dB; 0 dB is perfection, and the higher the
figure the worse.
19.21 Another Box Trick
In Sec. 12.5 we introduced a box with two terminals whose electrical
properties were not what would be expected from its contents. Here
is another example of such a box. This time a sinusoidal voltage
applied to the terminals gives rise to a ...