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Old March 23rd 09, 10:44 PM posted to rec.radio.amateur.antenna
Joel Koltner[_2_] Joel Koltner[_2_] is offline
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First recorded activity by RadioBanter: Dec 2007
Posts: 133
Default Noise figure paradox

Hi Richard,

"Richard Clark" wrote in message
...
This is comparing elephants to oranges.


Not intentionally; I misunderstood your objections.

The whole point of the exercise was that just starting with an SNR doesn't
provide enough information to do anything useful relating to noise figures,
although I didn't realize when I posted it that specifying "an antenna" is way
too vague.

So, you came up with 60 dB, what was the noise level in?


To be consistent with what I was trying to concoct, the noise level would have
been kTB with T=290K.

Here's a question for you: What's the noise output power of your
run-of-the-mill RF signal generator (e.g., an HP 8594A/B/C)? I'm thinking the
noise output power is *well* in excess of kTB (where T is the room temperature
you're operating the generator in)?

---Joel