(Dan Dugan wrote:)
> Great. Do you have the NSS Newsletter report of my mike preamp
tests of several years ago? It's time for an update.
Yes, I believe I do.
> The EIN is a signal level usually expressed in dB, like "-129
dBm."
> The difference you describe is called something like "noise
figure," I think.
Whoops, am I embarrased. Yes, I reversed the terms. EIN is the
actual voltage level of the noise on the input, determined by
measuring the noise on the output and subtracting the gain.
NF, or Noise Factor, is the difference in dB between that
measurement and the theoretical noise level of a resistor with the
specified source resistance (-129.6dBu I believe for 150 ohms --
I'll have to look that up).
Thanks,
Adam
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