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FCC Prohibits Blocking of Personal Wi-Fi Hotspots

Muad'Dave Re:It was never not prohibited (128 comments)

I understand Part 15 (as well as Part 97, since I'm licensed under those rules). The mechanisms mentioned in the GP _do_ exist in law for 5GHz U-NII (read WiFi) systems. Please refer to Title 47 Part 15, Subpart E, particularly 15.407(h)(1) and (2) and also 15.37(e).

Also, (if I read it correctly) 15.37(h) forbids the marketing or sale of devices that use any digital modulation technique other than Spread Spectrum operating in the 5725-5850 MHz bands starting on June 2, 2016.

The definition of "digital modulation" is distinct from SS - from 15.403(f):

(f) Digital modulation. The process by which the characteristics of a carrier wave are varied among a set of predetermined discrete values in accordance with a digital modulating function as specified in document ANSI C63.17-1998.

3 days ago
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Gamma-ray Bursts May Explain Fermi's Paradox

Muad'Dave Re:Fermi's paradox is hubris (236 comments)

with 2.5 Watts I can talk to 30 people around the globe using PSK31 or Wspr.

I've got that record beat at least on WSPR. I xmitted on 30m using 100mW from central VA (grid FM17), and was heard in New Zealand. An amazing mode, isn't it?

3 days ago
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FCC Prohibits Blocking of Personal Wi-Fi Hotspots

Muad'Dave Re:It was never not prohibited (128 comments)

You're incorrect. Part 15 devices are absolutely required to not cause interference. From the link, emphasis mine:

(a) Persons operating intentional or unintentional radiators shall not be deemed to have any vested or recognizable right to continued use of any given frequency by virtue of prior registration or certification of equipment, or, for power line carrier systems, on the basis of prior notification of use pursuant to 90.35(g) of this chapter.
(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.
(c) The operator of a radio frequency device shall be required to cease operating the device upon notification by a Commission representative that the device is causing harmful interference. Operation shall not resume until the condition causing the harmful interference has been corrected.

3 days ago
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At Oxford, a Battery That's Lasted 175 Years -- So Far

Muad'Dave Re:Oops (211 comments)

Maybe she's trying to tell you to buy her a cordless vacuum.

5 days ago
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At Oxford, a Battery That's Lasted 175 Years -- So Far

Muad'Dave Re:Oops (211 comments)

My favorite was the coworker that set up a UPS on a server and left for the day. I got a call an hour later saying the server had stopped responding. It turns out that the coworker plugged the UPS INTO ITSELF, and left it running. From that day on his nickname was 'loopback'.

5 days ago
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TWEETHER Project Promises 10Gbps MmW 92-95GHz Based Wireless Broadband

Muad'Dave Nice atmospheric window, but rainfade KILLS (54 comments)

I always post to the wrong duplicate article! ~sarcasm

From my other post:

According to line 'A' on this graph, the atmospheric absorption at 95-100 GHz is fairly low, but this graph shows that rainfade is an absolute killer. Light rain contributes 1 dB/km, which amounts to losing 20.6% of your signal per km. After 10km, you're under 1% of your original signal.

Somewhere between medium and heavy rain you cross the 10 dB/km line - you lose 90% of your signal per km. That ventures into 'unusable' territory very quickly.

about a week ago
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Apple Agrees To Chinese Security Audits of Its Products

Muad'Dave Re:Absolutely fair.. (114 comments)

In a world where several BILLION up-and-coming wage earners are ripe to purchase their products, which, incidentally, wouldn't exist if not for the cheap labor still extant in that very same country.

about a week ago
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TWEETHER Project Promises 10Gbps mmW 92-95GHz Based Wireless Broadband

Muad'Dave Nice atmospheric window, but rainfade KILLS (1 comments)

According to line 'A' on this graph, the atmospheric absorption at 95-100 GHz is fairly low, but this graph shows that rainfade is an absolute killer. Light rain contributes 1 dB/km, which amounts to losing 20.6% of your signal per km. After 10km, you're under 1% of your original signal.

Somewhere between medium and heavy rain you cross the 10 dB/km line - you lose 90% of your signal per km. That ventures into 'unusable' territory very quickly.

about two weeks ago
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Lost Beagle2 Probe Found 'Intact' On Mars

Muad'Dave Re:Design failure (130 comments)

Why you link an article about hypothetical nano technology is bejond me :)

Because it's fascinating, and it mentions the extreme energy density of other 'safe' radionuclides besides Plutonium 238. That was the question that was asked in the parent post, after all. :-)

As for efficiency, I bet a closed-cycle Stirling Engine system could work on Mars with Gd148 as the heat source and a radiative heat sink to space or the (almost non-existent) Mars atmosphere as the sink. Naturally you could parallel the Gd148 sources so that no one source exceeded the max temp for the engine. If you're not willing to do that, there are other non-moving solutions that beat the paltry 3-7% of an RTG.

about two weeks ago
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NJ Museum Revives TIROS Satellite Dish After 40 Years

Muad'Dave Ah yes, Fort Monmouth (28 comments)

I remember seeing that dish when I worked at Concurrent Computer in nearby Oceanport. I also volunteered at Ft. Monmouth during the 1st Gulf war operating their Army MARS station AAR2USI providing comms between deployed soldiers and their families stateside.

about two weeks ago
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Sysadmin becoming director ?

Muad'Dave Sadly, the only option ... (2 comments)

... IMHO is to walk away before you lose you marbles tilting at windmills.

about two weeks ago
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Lost Beagle2 Probe Found 'Intact' On Mars

Muad'Dave Re:Design failure (130 comments)

You assume RTG technology - I don't and I don't think the linked article does, either.

They discuss Energy Organs here, stating that (emphasis mine):

a sphere of Gd148 emitting ~100 watts with a 75-year half-life and measuring 3.41 cm in diameter with a 5-micron Pt shield glows at 1326 K (e-sub-r for Pt at 1326 K is 0.156; Gd melting point ~1585 K, Pt melting point ~2042 K); this is approximately the decomposition temperature of diamond (into graphite) and well above the combustion point for diamond in air (Section 6.5.3), so Pt-coated sapphire (sapphire melting point ~2310 K) may provide a more stable first wall for the radionuclide energy organ. Carnot thermal efficiency for a heat engine using this source could reach, at most, ~76%.

I'd say that's pretty good efficiency, and given the power levels and temperatures, I think non-RTG technologies should be used. If the system never drops below 0C, why not use a more conventional system?

Plus, you could just use the Gd148 to keep the craft warm and use other means to generate electrical power.

about two weeks ago
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Lost Beagle2 Probe Found 'Intact' On Mars

Muad'Dave Re:Design failure (130 comments)

Gd148 is sexy as hell, but isn't exactly available in the corner drugstore. I quote:

A ~0.2 kg block of pure Gd148 (~1 inch^3) initially yields ~120 watts, sufficient in theory to meet the complete basal power needs of an entire human body for ~1 century...

about two weeks ago
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Intuit Charges More For Previously Offered TurboTax Features, Users Livid

Muad'Dave Don't like it? Use H&R Block (450 comments)

I stopped using TurboTax when they decided they could write data outside my filesystem, as if it were their computer. I use H&R Block's TaxCut, and it's just as good as TurboTax ever was.

about three weeks ago
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Silicon Valley's Quest To Extend Life 'Well Beyond 120'

Muad'Dave Re:The longer you live...Cancer could be your rewa (273 comments)

Cancer may not have to be the cause of death, but rather the cause of immortality.

Perhaps they can harness the same thing that keeps HeLa cells immortal - sort of a body-wide 'cancer' that makes you immortal?

about three weeks ago
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Ask Slashdot: Sounds We Don't Hear Any More?

Muad'Dave The sound I'd like to hear again (790 comments)

The sound of a Saturn V ripping and rending it's way into space.

about three weeks ago
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Ebola Patient Zero Identified, Probably Infected By Bats

Muad'Dave Re:What's odd is that (112 comments)

Check out Strong Spermin' ^H^H^H^H Strom Thurmond. He popped out 4 kids between the ages of 68 and 73.

about a month ago

Submissions

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NRO to declassify Cold-War Spy Sat Tech

Muad'Dave Muad'Dave writes  |  more than 3 years ago

Muad'Dave (255648) writes "The National Reconnaissance Office is set to reveal details of two of the cold war's most capable spy satellite programs on September 17th — the GAMBIT and HEXAGON projects, aka the keyhole KH-7, -8, and -9 satellites. These bus-sized sats provided critical imagery during the height of the cold war, and were likely the inspiration for the movie "Ice Station Zebra".

The article links midway down the first page provide a fascinating look into the world of real spy-vs-spy, cloak-and-dagger intelligence gathering."

Link to Original Source
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US Air Force secret X-37B orbiter lands

Muad'Dave Muad'Dave writes  |  more than 4 years ago

Muad'Dave (255648) writes "The US Air Force's secret X-37B orbiter landed at Vandenberg AFB early this morning. Amateur satellite watchers determined the orbit and detected several orbital maneuvers. From the press release:

30th Space Wing Public Affairs

12/3/2010 — VANDENBERG AIR FORCE BASE, Calif. — The U.S. Air Force's first unmanned re-entry spacecraft landed at Vandenberg Air Force Base at 1:16 a.m. today.

The X-37B, named Orbital Test Vehicle 1 (OTV-1), conducted on-orbit experiments for more than 220 days during its maiden voyage. It fired its orbital maneuver engine in low-earth orbit to perform an autonomous reentry before landing.

The X-37B is the newest and most advanced re-entry spacecraft. Managed by the Air Force Rapid Capabilities Office (AFRCO), the X-37B program performs risk reduction, experimentation and concept of operations development for reusable space vehicle technologies.

"Today's landing culminates a successful mission based on close teamwork between the 30th Space Wing, Boeing and the Air Force Rapid Capabilities Office," said Lt Col Troy Giese, X-37B program manager from the AFRCO. "We are very pleased that the program completed all the on-orbit objectives for the first mission."

OTV-1's de-orbit and landing mark the transition from the on-orbit demonstration phase to a refurbishment phase for the program.

The Air Force is preparing to launch the next X-37B, OTV-2, in Spring 2011 aboard an Atlas V booster."
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Has NASA found ET?

Muad'Dave Muad'Dave writes  |  more than 4 years ago

Muad'Dave (255648) writes ""NASA is expected to make an announcement Thursday (Dec. 2) about a new scientific finding that 'will impact the search for extraterrestrial life,' the space agency said in a statement." Has NASA found ET, or just an exoplanet that looks promising? Maybe they found a fossil on Mars..."
Link to Original Source
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Target pharmacy begins scanning driver's licences

Muad'Dave Muad'Dave writes  |  about 5 years ago

Muad'Dave (255648) writes "This evening I picked up my regular prescriptions at my local Target pharmacy. As I was paying for them, the cashier asked to 'see my ID'. That was not typical, but I assumed she was going to verify the photo. Before I could stop her, she flipped it over without looking at the front and scanned the 2D barcode on the back. I asked her why she did that, and her answer was that the system 'required' it.

I went to the customer service desk and asked them why they thought they were entitled to scan my license. Their first answer was that it was a convenient way to validate my birthday, and that was all that was on the 2D barcode. When I mentioned that I know there's more data than that, she then said that it was a convenient way to verify that the ID was present. I mentioned that verifying the presence of an ID required more data than the DOB, and she agreed, contradicting her earlier statement that all they scanned was the DOB.

The is a Federal law addressing who can and cannot scan licenses, but it's so full of loopholes as to be useless.

Apparently I'm not the only one bothered by their attitude on privacy.

Have you been subjected to this invasion of your privacy by Target?"
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CircuitCity.com Rises From the Ashes

Muad'Dave Muad'Dave writes  |  more than 5 years ago

Muad'Dave (255648) writes "From www.circuitcity.com:

Systemax Inc. is Re-Launching the Circuit City brand with new Lower Prices, new Wider Selection, new Faster Shipping, and a better 24/7 Customer First Service Department.

Circuit City served American Shoppers for 60 Years. We're here to continue that tradition online with lower prices and special deals, a better selection of the products you want most, award winning customer service and same day shipping, starting at $1.99."
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Satellite debris forces ISS crew into rescue craft

Muad'Dave Muad'Dave writes  |  more than 5 years ago

Muad'Dave (255648) writes "CNN is reporting that the crew of the International Space Station was forced to take refuge from a possible collision of the ISS with a piece of space debris Thursday. From the article:

"Floating debris from a satellite forced the crew of the international space station to retreat to a safety capsule Thursday, according to a NASA news release. .. The debris was too close for the space station to move out of the way, so the station's 18 crew members were temporarily evacuated to a the station's Soyuz TMA-13 capsule, NASA said.""
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Cheap, super-efficient LEDs on the horizon

Muad'Dave Muad'Dave writes  |  about 6 years ago

Muad'Dave (255648) writes "According to this article, cheap Gallium Nitride LEDs are now possible, thanks to a process that controls the rate at which GaN shrinks when cooled, making it possible to grow GaN on silicon.

"They included layers of aluminium gallium nitride in their LED design. These layers shrink at a much slower rate during cooling and help to counteract the fast-shrinkage of pure gallium nitride. These LEDs can be grown on silicon as so many other electronics components are."

"A 15-centimetre silicon wafer costs just $15 and can accommodate 150,000 LEDs making the cost per unit tiny. That levels the playing field with CFLs, which many people only ever saw as a stopgap solution to the lighting problem.""
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Circuit City To Be Liquidated

Muad'Dave Muad'Dave writes  |  about 6 years ago

Muad'Dave (255648) writes "According to an MSNBC article, Circuit City Stores will be liquidating all of their inventory in 567 stores. Only a few years ago, Circuit City was the #1 electronics retailer, and its stock was over $100/share."
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Circuit City up against Jan. 16th 'hard deadline'

Muad'Dave Muad'Dave writes  |  about 6 years ago

Muad'Dave (255648) writes "Circuit City's lifeclock is winding down, according to this CNN article. The article states that Circuit City is such bad shape that "..it has until the end of next week to reach a deal with "interested" parties to help it stay in business or else it may have to start liquidating.

'Circuit City is coming up against a very hard deadline,' said Justin MacFarlane, director with turnaround firm AlixPartners. 'If they can't find a buyer [then] there's a real risk of the company going out of business.'""
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Election Poll Suggestion

Muad'Dave Muad'Dave writes  |  more than 6 years ago

Muad'Dave (255648) writes "How about a poll asking, "Who do you _want_ to win the election, and who do you _think_ will win the election?"
  • McCain/McCain
  • McCain/Obama
  • Obama/Obama
  • Obama/McCain
  • Cowboy Neal/Cthulhu
"
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The Re-Entry of ATV: One Final Experiment

Muad'Dave Muad'Dave writes  |  more than 6 years ago

Muad'Dave (255648) writes "The SETI Institute, in cooperation with the European Space Agency is organizing a mission to record the fiery breakup of the ATV/Jules Verne spacecraft as it re-enters Earth's atmosphere on September 29th.

From the article:

A documentation of the breakup process could help validate the models built to study how that fragmentation evolves in a series of disruptions of major components. At reentry into the atmosphere, ATV would execute one final experiment before the mission completion. Our experience with meteor spectroscopy carried the promise of perhaps being able to identify some of the fragments from their radiation signatures. The ATV-1 "Jules Verne" Multi-Instrument Aircraft Campaign was born. "
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Flying Spaghetti Monster spotted; magnet-powered!

Muad'Dave Muad'Dave writes  |  more than 6 years ago

Muad'Dave (255648) writes "Our Lord FSM has been spotted, and is apparently powered by giant magnetic fields. No word on when His Noodliness will approach our world.

From the article:
Long-lived magnetic fields are sustaining a mammoth network of spaghetti-like gas filaments around a black hole, a new study suggests. Previously, it was not clear what prevented the delicate filaments from being destroyed by competing gravitational forces. "
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Opportunity Takes a Dip Into Victoria Crater

Muad'Dave Muad'Dave writes  |  more than 7 years ago

Muad'Dave (255648) writes "From the NASA News Release:

Today, NASA's Mars Exploration Rover Opportunity entered Victoria Crater for the first time. It radioed home information via a relay by NASA's Mars Odyssey orbiter, reporting its activities for the day. Opportunity drove far enough in — about four meters (13 feet) — to get all six wheels past the crater rim. Then it backed uphill for about three meters (10 feet). The driving commands for the day included a precaution for the rover to stop driving if its wheels were slipping more than 40 percent. Slippage exceeded that amount on the last step of the drive, so Opportunity stopped with its front pair of wheels still inside the crater.

This marks the beginning of perhaps the greatest 'Opportunity' for new discoveries on Mars."

Link to Original Source

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