Owen Duffy wrote:
Jim Lux wrote in
:


Whilst it might be reasonable to assume that the combined error in
measurement of a high S/N sine wave voltage might be normally
distributed, and that might also be true of measurement of noise voltage
in some circumstances, I propose that measurement of noise power in
narrow bandwidth with short integration times is distributed as Chi-
squared and the number of samples becomes relevant in determining the
number of degrees of freedom for the distribution. For this reason, I
have talked about a confidence level rather than sigma (which is more
applicable to normally distributed data).

I would agree..

My question would be whether the original measurement (before averaging)
is normally distributed. I suspect it is, being essentially integrated
noise.