Noise figure paradox
Thanks for the clarifications, Ian. (OK, really, thanks for pointing out the
numerous errors I made. :-) )
"Ian White GM3SEK" wrote in message
...
All of these concepts originate from a classic 1944 IRE paper by Friis,
which recognized that noise factor and noise temperature must be related by
some arbitrary value of reference temperature - and that very same paper
suggests 290K.
It's interesting to me that, when I was in school, all the noise
figure/temperature stuff was done without Friis's name ever coming up...
whereas his name was prominently mentioned when discussing the path lose
relations (based on distances, antenna gains, etc.)
73 from Ian GM3SEK 'In Practice' columnist for RadCom (RSGB)
Speaking of interesting things, I've always thought that you RSGB guys tend to
produce books/articles/etc. at a rather higher technical level, on average,
than the ARRL does. The first time I was at Dayton and stopped by a booth
that George Dobbs was manning with various QRP kits and RSGB books, I must
have dropped $100. :-)
---Joel
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