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Good texts on application of White Noise for testing?

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6SN7WGTB:
Can anyone point me towards good texts/books/links/manuals for applying White Noise for audio and RF testing?

I'm aware of various uses but cannot seem to find any good compendiums.

Thanks

jonpaul:
6SL7

See,old,Genrad book, audio noise,measurement
white,noise,is for,RF, pink noise,is,3db/ Oct rolloff, flqt energy près octave,,1/3 oct

j

pdenisowski:

Noise figure testing with spectrum analyzers (Y-factor method) requires the use of a broadband noise source for the device under test input.

https://www.rohde-schwarz.com/us/applications/the-y-factor-technique-for-noise-figure-measurements-application-note_56280-15484.html

I also have a video on this topic that will be posted to the Rohde & Schwarz YouTube channel in the next week or two.

G0HZU:
The 1MA178 paper by R&S is an excellent reference if you want to do your own Y factor measurements because it includes step by step equations and worked examples.  HP/Agilent/Keysight provide AN-57 as an alternative. I'd recommend reading both.

I've got a lot of experience with noise sources and noise measurements, including NPR testing. The classic old book for NPR stuff was the White Noise Book by M.J. Tant (Marconi). However, this is very dated now and of limited use today. I still have my copy here.

For more general testing (with noise) the quality of the noise source is usually quite important. The crest factor, flatness vs frequency and the source VSWR are all important factors that affect the quality of the noise source. I've got quite a few noise sources here, mostly homebrew but all have very good performance. It's worth studying all the contributors to measurement uncertainty and also look at ways to preserve the crest factor of the noise source. An old rule of thumb at work was that the p1dB of any amplifier should be at least 14dB higher than the average power of the noise. It's generally best to aim for 16-18dB. This is important when designing/building a high level and wideband noise source for use as a bench instrument.


G0HZU:
Here's the classic old version of AN57-1 and AN57-2 by HP.

http://www.hparchive.com/Application_Notes/HP-AN-57-1.pdf

http://hparchive.com/Application_Notes/HP-AN-57-2.pdf

Some hints and tips in the link below for making better noise figure measurements:

https://www.ab4oj.com/test/docs/5980-0288E.pdf

To achieve low overall measurement uncertainty when measuring something like an LNA requires really good (and stable) test equipment. One also has to know which noise source and/or measurement method is best to use for a given task. I'm lucky in that I have a pretty good setup here for measuring the noise figure of RF amplifiers up into the GHz region.



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