"Joel Koltner" wrote in
:

"Ian White GM3SEK" wrote in message
...
An important misconception is about the role of "290K" as a reference
temperature. Contrary to what is stated above, this is *not* a
designer option ("usually 290K", implying that some other value could
be chosen).

Well, Owen was using 289K and Wes says, "the noise figure concept has
the drawback that it depends upon definition of a standard
temperature, usually 290K." Hence, while I certainly accept that "the
IEEE standard definition" is 290K, it seems to me that it's a bit of
wishful thinking to suggest that no one has ever used a different
reference temperature in their work.

Joel, you misunderstood my calc.

The 289K was the internal noise of the DUT with NF=3.00000dB. The reference
was (and must be) 290K.

Owen