As someone who lived in the Detroit area during the 80s and 90s and whose family members spent major portions of their careers employed by GM, I can say that the problems with American cars were not caused by insufficient engineering ability. The problems were the result of complacent and overly conservative management combined with a complacent and overly unionized manufacturing workforce. In the late 70s / early 80s, Complacency in management led to a situation where it didn't matter much what the engineers designed unless the design was for a cheaper version of something with a proven track record; the management effectively thought people would continue indefinitely to buy the same things that had sold well in the past. Instead of putting resources into developing what people were going to want in the future, they concentrated on lowering costs.

Attempts at factory automation were frequently sabotaged by factory workers who feared that humans would be replaced by robots. Pension payouts from the first big pile of pensioned employees were ramping up. Internal politics guaranteed that only "yes men" would get promoted. Basically, nobody was paying attention to the customer anymore -- the engineers were the only ones even paying attention to the product at that point.

They started turning things around in the early 90s, but they still haven't managed to overcome the reputation damage that was done during the 80s. They seem to have still not really managed to look beyond the market pigeon holes they currently occupy.

I have become aware over the last couple years that some companies have become so good at astroturfing that their efforts are almost undetectable as such. Microsoft is one such company. Starbucks is probably another. Companies like Starbucks probably do benefit from it simply because all they really need to do most of the time is remind people that they exist.

Amazon has been plugging the Kindle pretty hard...

Is for the FSF or some other trustworthy organization to commit a patent spam atrocity that involves patenting all sorts concepts related to generating patent applications. Perhaps they can patent the abstract concept of a mental algorithm by which numerous obvious patents can be generated from a single thought. Maybe they should go all the way and patent the abstract concept of a mental algorithm -- just make thinking an activity that might cause expensive litigation while simultaneously making thinking about litigation a cause of potentially expensive litigation. Before long, everyone who even likes to dabble in the realm of patent spam or patent related legal asshattery will be locked in a litigation loop until they die of dehydration. It will be like a virus that does a while(1) { fork(); } to the patent trolls.

Microsoft has always been robustly anti-competitive. As TFA shows, they aren't even trying to hide the fact that the passion behind their "kick-ass product" is really more like the passion of a temper tantrum than the passion of someone creating something that kicks ass.

Microsoft used to at least be clever about their anti-competitive behavior. Now that Bill Gates left and they aren't even good at being anti-competitive any more, they're basically just an 800 pound retarded, spoiled, wealthy gorilla toward which almost nobody has any remaining good will. I can't imagine that a company more concerned with destroying the competition than with satisfying customers can continue being profitable forever. I am having a hard time seeing how they are going to get themselves out of the predicament they are in, (especially when they don't seem to understand that they are in one.) I suspect they might have to pull an IBM and almost go bankrupt before they finally get around to curing their cranio-rectal inversion.

I know P ~ V^2 assuming constant impedance. I am not arguing with you about the physics. "3dB" does not include any information about units. "3dB" is a ratio, it doesn't care what it is a ratio of. "3dB" is a purely quantitative concept. "3dB" can apply equally to elephants, libraries of congress, Volts, or kielbasas.

My post about "3dB" being conceptually equal to "200%" is correct because "3dB" has nothing inherently to do with power or voltage or anything except a *ratio*. Only if one adds units to it, can it *imply* a *ratio* of something.

"3dB" is the same thing as "2:1", "2", "200%", "2.0x10^0", "0x02", "2/1", "16/8", "two to one", "two" and "II". "2" does not mean "2 Volts" or "2 Watts" or "2 overly pedantic slashdot posts" or 2 of anything else unless you put units after it to indicate that it is supposed to mean *two of something*. "3dB" is in the same unitless boat as "2". I can say "I have 200% of the chickens I used to have" or "my chicken gain is 3dB" and either way, I will be saying the same thing, because "200%" is a ratio, (200:100), and so is "3dB", (2:1), and (200:100) == (2:1).

Any ratio can be expressed in deciBels; to do so, one takes one's ratio, takes the base-10 log of it, and multiplies that result by 10. This final result is the ratio in deciBels. *That* is how deciBels are defined, regardless of what their application is or what the ratio represents. Any definition of the deciBel where the ratio 2:1 equals anything other than 3dB either has the deciBel confused with something else or is confusing the definition of the deciBel with the definition of whatever they are trying to use them for.

The assertion that deciBels are a unit of signal strength is wrong unless, by "signal strength", you mean "signal-to-noise ratio." DeciBels can only quantify signal strength when they are used in conjunction with a reference signal strength and then they only describe signal strength as a ratio relative to the reference one. If you want to call deciBels units of something, they are a unit of *ratio*, and that is *all* they are. They are not inherently a unit of signal strength, sound pressure, voltage, power, or anything else. There is not a physics book in the known universe that disagrees with me about this if you read it carefully. When someone speaks of "signal strength" in "dBm", like other posts have pointed out, they mean a quantity of power or voltage relative to 1mW or 1mV respectively -- a ratio of mW to 1mW or a ratio of mV to 1mV. "dBm" != "dB".

Again, you are right that P ~ V^2. You are right that when you change the voltage by a ratio of 1.414:1, you get a change in power of 2:1. When the ratio of (power now):(power before) is 2:1, when before turned into now, the power went up by 3dB. When the ratio of (voltage now):(voltage before) is 1.414:1, when before turned into now, the voltage went up by (10*log10(1.414))dB.

If you want to indicate that P~V^2 using deciBels, you could say that a 3dB increase in voltage implies a 6dB increase in power, or that the ratio of the power ratio to the voltage ratio is 3dB. Anyone who simply states in a textbook, (textbooks are supposed to be clear and unambiguous,) that a 2:1 ratio comes out to an unqualified "6dB" when the ratio happens to represent voltage and then provides a formula to make it work out that way is suffering from cranio-rectal inversion. It always has been and always will be incorrect. If your textbook says otherwise, whomever wrote it should be soundly chastised after having their cranio-rectal inversion cured. :)

I realize that this post has exceeded standard allowable limits of pedantry, but if you will refer to my initial post, you will see that I summarized this problem by saying something about someone turning a voltage knob while reading a power meter and incorrectly claiming that a factor of 2 is 6dB. The problem is not that they are wrong about the physics, the problem is either that they don't really understand what "6dB" means or they haven't explained that they are turning a voltage knob but measuring power, thereby making their ratio a ratio of two different kinds of things where X units of one thing really does translate into X^2 units of the other.

I know dBm is widely accepted. It is ubiquitous in the optical communications world too. Most optical power meters designed for telecom-type usage measure optical power in dBm by default. For that matter, "dBm" is also commonly used to mean "dB relative to 1mV." I'm also aware that nobody uses "dBm" to mean "dB relative to 1/1000th," but if we are being pedantic, "dBm" means nothing more than "dB relative to 1/1000th". This was the point in my first post.

I have no problem with dBmW, dBmV, or dBm for short where there isn't ambiguity about what the units are. Those "factor of 2 == 6dB" people piss me off though. They are taking a nice, clean, useful concept and notation and totally screwing it up. They are also just wrong.

Things like signal-to-noise ratio and amplifier gain are usually specified in "dB". This usage is correct because the quantity always refers to a ratio of two quantities of the same thing.

Kakari said it best: the ratio 2 (in dB) == 10*log10(2)dB == 3dB *always*, because that is the definition of the *deciBel*. Note here that I am not talking about dBmW or dBmV or dBm -- just "dB". The ratio 2:1 can be a ratio of voltages, powers, elephants, whatever, it doesn't matter as long as the ratio compares some quantity of something against another quantity of the same thing. If one wants to express a ratio (2:1) of voltages in dB, one cannot correctly use 20*log10(2) = 6dB, because 20*log10(ratio) is not how one calculates deciBels! These should be called "dodeciBels" or some other conglomeration of "Bels" and a prefix that means 1/20th, but not "deciBels", because it just doesn't make sense. This is like saying "percent" sometimes means "out of 200" instead of "out of 100" depending on what the quantity in question is a percentage of. Nobody who understands that "cent" refers to 100 and "per" refers to something like "for each" would take an "out of 200" definition of "percent" seriously.

This 20*log10(ratio) stuff is bullshit I tell you!

(storms off)

The whole point of a "signal strength" meter is so that one can determine when one is approaching a "no signal" zone and so that one can determine how well their phone will work at a given location without having to make a call. It is disappointing that traditional signal strength meters (with 3-6 "bars") fail to do this reliably.

You can tell if the phone will work or not should you try to make a call or transmit data by a simple on/off indicator like you said. If the meter just displayed the S/N ratio, it would be the equivalent of having a traditional meter with lots of bars. This would convey more information, probably take up less space on the display, and allow people to generate detailed enough data that they might be able to fix things in places where performance is bad.

The problem of large or mysterious numbers could be remedied by offsetting the value by some fixed amount so that "0" is where the S/N ratio is so bad that the phone can't do anything.

I'm all for it.

To further add to the pedantry, I would like to point out the following:

In the beginning of the Wikipedia article about the venerable dB, it points out (correctly) that decibels are used to denote ratios and are therefore inherently devoid of units. When discussing the decibel, we are discussing only numerical notation here, not physics.

The Wikipedia article (correctly) stops just shy of stating that the decibel is inherently related to physical concepts like electric field strength, power, and pressure. One does not define "percent" as being inherently related to financial concepts. For the same reason, one should not define "decibel" as being inherently related to physical concepts. Writing "-10dB" is *exactly* the same conceptually as writing "10%". Writing "3dB" is conceptually *exactly* the same as writing "200%". The fact that I have never seen the annual yield of a savings account expressed using dB does not mean that it isn't correct to do so.

To be slightly but meaningfully pedantic, "dBm" should be interpreted effectively the same way "dB" is, (except you should add 30 to it -> 0dB == 30dBm,) because there aren't any units present. The "m" just adds the "milli" prefix to a unit that isn't stated. If you mean dB relative to 1 mW, you want dBmW. If you want dB relative to 1 mV, you want dBmV. If you've ever had an argument with someone about whether a "factor of 2" is 3 dB or 6 dB, this is usually because the 6 dB guy is unaware that he is turning a voltage knob but measuring the resulting change in power. If you have ever had this argument, you are probably a geek. (Just for posterity, a factor of 2 == 3dB *always*.)