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Comment: Re: Running kismet on a laptop (Score 5, Informative) 152 152

One of the Part 15 rules is about not interfering, and clearly that's not working out so well.

I don't believe the FCC cares about Part 15 devices interfering with other Part 15 devices. From the rules:

CFR 47 Part 15.5

(b) Operation of an intentional, unintentional, or incidental radiator is subject to the conditions that no harmful interference is caused and that interference must be accepted that may be caused by the operation of an authorized radio station, by another intentional or unintentional radiator, by industrial, scientific and medical (ISM) equipment, or by an incidental radiator.

(boldface is added for emphasis)

In other words, a Part 15 device that interferes with another Part 15 device is cool, since Part 15 devices are offered no protection from interference, intentional or unintentional.

The law is written so that Part 15 devices are not allowed to interfere with licensed devices.

Comment: Re:the world was supposed to end years ago (Score 1) 637 637

why not put fluoride in the soft drinks?

The government considered doing this, but concluded it would be too risky, due to the likelihood of massive overdoses of fluoride to much of the population. Much safer to deliver it in the water supply.

Comment: Re:Good news (Score 1) 391 391

"Melinda Herman shot the intruder five times, hitting him in the face and neck. Chapman said she told the man if he moved she would shoot him again, although she had run out of bullets."

(To be technical here, she was a "good girl". But I think you'll accept that gender isn't a factor here.)

"Mark Vaughan, the company’s founder, chief operating officer and a reserve sheriff’s deputy, was on site at the time and shot Nolen, stopping the attack before police arrived, Lewis said."

(Mark Vaughan may have been a reserve sheriff's deputy, but he was off duty, which meant he was a regular citizen "good guy"

Oh heck, I'll let the NRA show you. Note: There are 660 pages of these in their files.

Comment: Re:Clarifications - MOD UP (Score 1) 47 47

On the basis of trusting that the AC truly is one of the authors (of the scholarly paper), I want to thank you for these clarifications and suggest to all to mod that post up. It definitely is better than score: 1, which is its current value at the time of my writing.

110 dB of SI cancellation is beyond impressive - it is approaching magical!

On the face of it, this capability will double capacity of any RF channel for which it will work. AC claims this can be made to work on channel bandwidths exceeding 20 MHz, therefore making it useful for WiFi.

But I think there are other advantages. If a traditional system uses FDD (frequency division duplex) to achieve duplex (simultaneous transmit and receive) operation, then this new technology reduces by half any discrete RF/IF filter hardware needed to reject out-of-channel energy. That will help make the electronics simpler and less expensive. For FDD, the cost of the filters goes up as the two channels (transmit and receive) get closer together (the closer TX is to RX, the steeper the filters have to be to achieve adequate rejection). With this all-silicon approach, the most you need is bandpass filtering for the ONE channel you are using. Big win!

But then maybe I am exposing my dinosaur-like thinking in even bringing up discrete RF filter components. A recent announcement at Mobile World Congress touted a silicon-only radio technology that didn't appear to need any discrete filtering at all.

Also my (dinosaur-vintage) thinking about cellular base stations is that they generally operate in the +40 to +50 dBm range (out of the PA, prior to duplexers, etc. and not considering antenna gain), which implies another 20-30 dB isolation is required (vis-a-vis the AC's claim of 110 dB) to achieve the same isolation one would need in a cellular system. But then I'm not considering antenna gain which seems (without thinking about it too hard) to potentially improve the isolation if separate TX and RX antennae are used at the base station. Then again, I'm thinking macrocells here. But for a single channel duplex RF technology to be deployable in cellular, I think one would need to cover the macrocell case - in any case.

Comment: Re:They are going big into alternative energy (Score 1) 163 163

Next to that, we need a system of converting CO2 from the air into a usable fuel, ideally propane, because propane is not a greenhouse gas and inert.

Really? My reading is that the equation for propane combustion is: C3H8 + 5O2 = 3CO2 + 4H20

Maybe propane produces less CO2, pound for pound, than say, coal. (I don't actually know, and don't care to look it up.) But it certainly produces CO2 when burned.

Oh, and anyone who's ever cooked on a propane grill, or used a propane torch, will attest to its distinct non-inertness...

Comment: Re:the solution: (Score 1) 651 651

Unfortunately, a small, aggressive, well-funded minority can always subvert the democratic process.

If by this, you are obliquely referring to the NRA (as the aggressive, well-funded minority), you might take note that right now in Washington State, billionaires are out-spending the NRA (and pro-gun overall) by a ratio of 7 to 1 on an initiative to expand background checks. Well, at least that is what they are calling it. It's a whole lot more than "simply" expanding background checks, but I digress...

Said billionaires include:

Bill and Melinda Gates, Paul Allen, Steve Ballmer (gotta love all that Microsoft money slushing around)

Nick Hanauer


and Michael Bloomberg.

I particularly thrilled at how Ralph Fascitelli of Washington Ceasefire recently invoked the imprimatur of Dan Satterburg (King County prosecutor) as a supporter of I-594, while not mentioning the rest of the state (King county is a little over a quarter of the state's population). This was, of course, to a Seattle audience (who would care about the rest of Washington's population - how?).

Comment: Time for a Pedantic Rant (Score 1) 73 73

Wi-Fi is not a wireless communications standard. IEEE 802.11 is the wireless communications standard. Wi-Fi is a registered trademark of the Wi-Fi Alliance - and industry trade organization. They do publish interoperability agreements and offer "certification" (required to use their trademarks on products), but these should not be confused with the IEEE wireless communications standard.

(rant done - going back to reading now...)

Comment: 23 years later and we get it! (Score 3, Interesting) 73 73

I'd like to take a moment to memorialize a pioneer in this pursuit that probably none of you ever heard of. The name is Jim Lovette. Jim worked with me at Apple in the early 90's. He was a heart-and-soul devotee to the democratization of RF bandwidth for high speed data communications. With Jim's leadership, Apple drafted a petition to the FCC, known as Data-PCS. This was a proposal to allocate spectrum in the U.S. exclusively for use in data communications (as opposed to "voice only" which was the vogue at the time). The Data-PCS petition caused a lot of excitement, but did not result in anything earthshaking as an outcome. Still it started a movement of which this latest step is a grand one in the pursuit of "computing devices talking to each other" being equally important to "people talking to each other." Jim (and our team) were also early promoters of wireless LAN, which we all know today as WiFi. The IEEE 802.11 committee had just formed. Apple's early foray into wireless LAN preceded the availability of IEEE 802.11 (aka WiFi) products, and never made it to market. Apple chose instead to introduce their first wireless LAN products as 802.11b (11 Mbit/sec) WiFi. And over 20 years later, look what it has become?

Jim passed away in 2002, leaving us with a legacy of which few outside the cloistered Wireless LAN industry would even know he contributed so much. Thank you, Jim.

Comment: Exponential growth (Score 1) 267 267

Moore's Law is an expression of exponential growth. All we are seeing is the logical conclusion of applying exponential growth expectations to a real world finite resource (i.e. the fact that atoms have an essential finite size). See Wheat and Chessboard problem for reference.

Comment: It's TLER -- Re:Warranty isn't the only factor (Score 1) 270 270

"... but also, the firmware is different. They claim that drives intended for the consumer / SOHO market spend a lot of time retrying marginal reads before declaring an unreadable sector and sparing it. They say that SAN-class drives limit the retry time, because the array controller handles it more efficiently, since it has the big-picture view."

What you are describing is known as TLER or "Time Limited Error Recovery" (the Western Digital name for it, at least). See TLER

I've never been canoeing before, but I imagine there must be just a few simple heuristics you have to remember... Yes, don't fall out, and don't hit rocks.