High Quality White Noise Gen

GC can't but ICP-MS can. I worked on techniques used to prove provenance of very expensive French wines a long time ago based on the pattern of various alkali metals and rare earths present at ultra trace levels. We required about 10ml of wine of which only a couple of ml were analysed. That left the rest of the bottle to be disposed of.

They were concerned about rather high quality forgeries. A more recent paper (not by our group) but using similar kit is online at:

SIRA can also spot adulteration by adding cane sugar to grape juice.

Regards, Martin Brown

Reply to
Martin Brown
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Beats me. Why not ask a wine-maker? In theory, the mineral content of the water could influence the volatile organic compounds that give wine its odour and flavour, but I'd be surprsied if the comment was much more than decorative verbiage.

The GC can detect what you can smell, with somewhat more discrimination, allowing a more rational approach to wine-making than was possible in previous centuries, not that the more subjective approach couldn't produce great wines.

-- Bill Sloman, Nijmegen

Reply to
Bill Sloman

In other words, delusional fat-headedness. There's a lot of that going around. He should be careful about chewing on rocks... it's bad for your teeth.

So the GC knows more about what wines I like than I do?

No, thanks. The Bandit tastes great.

John

Reply to
John Larkin

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Fun.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal
ElectroOptical Innovations
55 Orchard Rd
Briarcliff Manor NY 10510
845-480-2058
hobbs at electrooptical dot net
http://electrooptical.net
Reply to
Phil Hobbs

Hobbs

photo-detection.

includes

of

10

I've always ignored Hre up to now, because it's generally swamped by other parameter variations. I certainly never had a reason to map Hre vs Ie and Vce.

The Fairchild 2N3904 datasheet actually has a curve, sadly only at 10 volts.

I don't have a lot of "academic curiousity"... I'm motivated by solving real problems. I've never before explored nanovolt-noise-level LDO regulators because I'd never needed one. Given an essentially infinite list of things to explore, I'd just as soon pick the ones that are potentially useful. Exceptions occasionally made for super-cool stuff, of course.

John

Reply to
John Larkin

Hobbs

photo-detection.

includes

accuracy

orders of

time is 10

-

absence

Children are cute as a defense against their parents strangling them. Then they become teenagers, and are strong enough that you can't easily strangle them.

John

Reply to
John Larkin

Hobbs

 wrote:

photo-detection.

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"Cute" is a programmed emotional response, triggered in order to cause you protect, or at least not to harm relatively harmless creatures you share DNA with. Baby snakes are perceived as less cute than puppies, which are in turn perceived as less cute than human babies. Dogs may have a different perspective on the matter.

Reply to
Spehro Pefhany

-

It's not all delusional fat-headedness, though publicists do latch onto to some of the more impressionistic terms as a basis for the inevitable chunks of decorative verbiage.

There are wine-tasting terms that most people understand - "slatey" and "grassy" comes to mind - even though the connection between the word and the flavour is somewhat arbitrary. My wife describes particular wines as "pink" by which she seems to mean having a high concentration of a particular floral ester. If we had a GC we could probably tell you which floral ester.

People - like you - who don't pay much attention to what they are drinking, and don't develop a vocabulary of terms that allow them to talk about the differences between particular wines, defensively devalue the comments of those who have tasted a wide variety of wines and can articulate the differences between them.

The GC doesn't know anything. The wine-makers who look at the results of gas chromatic analysis of their wines (and those of others) know a great deal more about wines than you do, and - given a short list of wines that you do like - and could probably predict what other wines you would like a great deal more reliably than you could.

If enough people share your opinion, it will get to be expensive and hard to find, and you would want to find something that tastes similar and is less widely known. If you could describe what it tastes like in terms that a wine critic or a a good wine merchant could understand, the process of finding an alternative would be easier.

-- Bill Sloman, Nijmegen

Reply to
Bill Sloman

Right. Fatheads. Hilarious failures in double-blind tests.

No, There are lots of inexpensive, great-tasting wines. Cynthia, the wine buyer down at Canyon Market, puts out stacks of good, cheap stuff.

John

Reply to
John Larkin

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Fatheads do fail ludicrously on double-blind tests, but blind tasting is popular amongst wine buffs, and some people do remarkably well. Some of their success has nothing to do with the taste and smell of the wine - one of my wife's colleagues paid particular attention to the shapes of the bottles, which provide useful extra information and someone who knows what the wine merchants have been pushing in the week or so before a wine tasting can have a pretty fair idea of what might being offered at a blind tasting - but people who know wine can get a lot from the aroma and taste.

There are lots of inexpensive good-tasting wines. "Great" implies something more, and great wines don't stay cheap and available for very long. The invisible hand of the market guarantees that. Cynthia will tell you all about it if you ask her nicely.

-- Bill Sloman, Nijmegen

Reply to
Bill Sloman

n't

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If not aroma and taste, what are they judging for?

an

Reply to
Richard Henry

wine-

The three 'C's. Clarity, Cost, and Condesention.

Reply to
krw

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Condescension. In fact, blind tasting of wines is aimed at identifying the wine being tasted. Which grape it was made from, which country it was grown in, which area in that country, which year?

Some wines are easier than others. Bordeaux from the Margaux area has a characteristic scent of violets which even quite unsophisticated palates can detect.

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-- Bill Sloman, Nijmegen

Reply to
Bill Sloman

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Actually differencing them in twos, then summing seems more likely to reduce the asymmetry.

Reply to
JosephKK

Sl>>>

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And that is where you tripped yourself up. Sums of lopsided signals are still lopsided. Differences may work better.

Direct from the nature of the I-V curve.

Reply to
JosephKK

Do I now have to explain to you what the word "inverted" means?

I don't see that. Please explain.

John

Reply to
John Larkin

When did addition stop being associative?

John

Reply to
John Larkin

Then

Perhaps when you do it with an op-amp.

(10+10)-(10+10) clips

(10-10)+(10-10) doesn't

That would be a whole lot of noise spiking :)

Reply to
MooseFET

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Differences will work better, but simple adding works too! The sum may still be lopsided, but less lopsided than the input. It's the Gaussian nature of shot noise (very asymmetric if you could look fast enough.) that made me reassess my previous misconception. (As a recent =91convert=92 to the central limit theorem I=92m perhaps more ardent than those with long held =91belief=92.)

George H.

Reply to
George Herold

Then

random

mA

The signals (zener noise) are mildly asymmetric noise, not DC values. When you add noise, it doesn't matter what order you add or subtract them in.

And besides, a true Gaussian distribution has probability tails to infinity; the opamps have to clip once in a while. A rational designer would just makes sure it doesn't happen often. [1]

JKK is so eager to be right, and for others to be wrong, he makes a lot of stupid statements. He's not the only one.

Allow me to pass on what Miss Denton taught me in 6th grade:

Check your work.

John

[1] summing computer-generated random numbers results in a distribution with finite peaks, basically Gaussians with their tails clipped. That can be handy.
Reply to
John Larkin

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