This is a complex answer. Noise must be compared to something, such as a standard. The noise in a component such as a resistor would be dependent on factors such as the temperature of the device, the current through the device, the applied voltage, the frequency of the voltage, waveform or structure of the applied voltage, and the humidity if the resistor is of a high enough value. These are only the simple attributes that I can think about at this time.
As for noise measurements, they are usually compared or scaled to some type of reference. You can measure the noise in simple volts, but this would be meaningless by way of definition unless you have a standard to compare it to. When publishing the noise factor, all the conditions of the test must also be specified.
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Greetings,
Jerry Greenberg GLG Technologies GLG
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