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Comment: Yes (Score 1) 1

by Muad'Dave (#49111811) Attached to: Question:Suggestions for a UPS with a 20 year battery life expectancy?

You have a funny way of spelling 'generator'. Choose a gaseous fuel model (natural gas, propane - whichever is handy) and let it rip. You could also install a fuel cell since it would only run a few times/year. Holding the power while the switchover happens is still an issue, but a battery that's over-spec'ed by a fair margin might be able to hold 20 secs of runtime after 20 years.

Comment: Re:That is close! (Score 1) 117

by Muad'Dave (#49080683) Attached to: Another Star Passed Through Our Oort Cloud 70,000 Years Ago

I doubt that the star is a magnetar, but it's "magnetically active" per the article - if it were active enough it may have had some influence on our magnetically active core and/or magnetically-sensitive ionosphere. Earthquakes followed by volcanos or more likely additional radiation due to perturbations of the ionosphere.

Comment: Re:It was never not prohibited (Score 2) 129

by Muad'Dave (#48926053) Attached to: FCC Prohibits Blocking of Personal Wi-Fi Hotspots

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.

Comment: Re:It was never not prohibited (Score 2) 129

by Muad'Dave (#48922879) Attached to: FCC Prohibits Blocking of Personal Wi-Fi Hotspots

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.

Simplicity does not precede complexity, but follows it.