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User: Phreakiture

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  1. Re:Lets see some real test data on Possible Big Boost in WiFi Range · · Score: 1

    Cellular phone towers already do exactly this.

  2. Re:Damn on DOJ Blocks Satellite TV Merger · · Score: 1

    I got Dish, based on $$. Here is the logic:

    Three comparable packages: AOL/Time Warner cable, digital service. Approx 100 channels. DirecTV's 100 channel package. Dish Network's 100 channel package.

    AOL/TW wanted $25 to do the installation (required), $40 for the first month, $50 for the second month, $60 for each month thereafter. They own the equipment, so no purchase price there. First year total: $715, $600 each year thereafter.

    DirecTV wanted $50 for the dish, and $32/month for service. Free installation (optional--you can DIY). First year total: $434, $384 each year thereafter.

    Dish wanted $200 for the dish, and $9/month for the first 12 months of service, $31 each month thereafter, again free installation (optional--you can DIY). This went up shortly after to $10/$32, but it still works out. Original annual cost: $308 for the first year, $372 each year thereafter. After the rate hike, this goes up to a still-respectable $320 for the first year and $384 each year thereafter.

    Synopsis: For 100 digital channels, both dish systems blow away cable on cost, and Dish edges out DirecTV by a small margin.

    Of course, both dish systems blow away digital cable on picture quality.

  3. Re:It's all a sham. on DOJ Blocks Satellite TV Merger · · Score: 1

    unless you're in a particular local broadcast market, you're not allowed to receive channels in it - even if the equivalent channel doesn't exist in your area, or no local service is available for your area! I.E. I can't get UPN nor WB via satellite, despite the fact that they are actually broadcasting it off the same bird I would receive from.

    You must be on DirecTV, then, because I have no problem get this service from Echostar. It's called the Superchannel Pack, and consists of three WB's and two UPN's for $5/mo.

  4. NOT RELEVANT (Was: Electricity Taxes) on Toyota to Move to All Hybrid Vehicles By 2012 · · Score: 2, Insightful

    A hybrid generates its own electricity. You do not plug it in. Its efficiency comes from the fact that it makes for a more even distribution of the energy produced by burning gasoline.

    Why are so many people not getting this point?!?

  5. Re:Future costs? on Toyota to Move to All Hybrid Vehicles By 2012 · · Score: 1

    Watch out on those maintenance schedules! My Subaru Impreza also lists a 7500mi/6mo service interval, but it has a great big asterisk next to it warning that frequent short trips (such as my 9-mile commute) qualify as extreme conditions, and reduce the interval to 3750mi/3mo.

    Of course, this may be different on a hybrid. The engine does not run as much, and it has this oddity of inverting the traditional relationship between city and highway gas mileage (i.e. highway gas mileage is less, rather than more, than in-city). This implies that the car was optimized for in-city driving.

  6. Re:Map of the radio spectrum? on FCC Approves Digital Radio, Kills Satellite Merger · · Score: 3, Informative

    The technology is called IBOC, which stands for In Band On Channel.

    The technology works by using the portion of the 200kHz space that is allocated to every FM station, that the station is not using at that exact instant.

    The original choice of 200kHz spacing was set up by observing the nature of FM. The carrier was allowed to deviate from its center frequency by up to 75kHz in either direction. This deviation is used to encode the information onto the carrier.

    Audio is added to this carrier at a maximum frequency of 15kHz. The transmission of a 15kHz tone on a carrier, AM or FM, will result in sidebands (think "aliasing artifacts") developing on either side of the carrier at 15kHz away from the carrier.

    Since the carrier is modulated by changing its frequency, if we modulate this carrier with a 15kHz tone at what is called "full deflection", i.e. we move it a full 75kHz above centre to a full 75kHz below centre, then the whole amount of spectrum required to do this will be 180kHz. This is 90kHz either side of the centre frequency.

    Sanity check: The lowest-frequency artifact will be the lower sideband at the point when the carrier is at its maximum negative deflection. This will be the centre frequency, minus the deflection (75kHz) minus the width of the sideband (15kHz). This, in turn will be 90kHz below the centre.

    Similarly, the maximum frequency artifact will be the upper sideband at the point when the carrier is at its maximum positive deflection. This will be the centre frequency, plus the deflection (75kHz) plus the width of the sideband (15kHz). This, in turn, will be 90kHz above the centre.

    For stereo broadcasting, some additional, ultrasonic information is added to the carrier (this information is done via a transformation that is beyond the scope of this description). This higest frequency of the modulated data becomes 53kHz as a result of this. This, in turn, is not modulated to full deflection, so it still remains within the permitted space.

    For digital broadcasting, the digital data will be carried by a non-FM technique, and will be put together in concert with the analog FM signal. This signal will then be modulated in such a manner as it dodges the current location of the carrier. How?

    From my previous description, you can see that the carrier and its sidebands will, at any given instant, only occupy a 106kHz chunk of spectrum (carrier + both sidebands) for stereo, or a 30kHz chunk of spectrum for monaural. The remaining 94kHz or 170kHz of allocated space is empty. The digital data is placed there.

    Now, I hear you asking, won't this cause interference to the analog signal? Ths short answer is yes. However, as long as the digital signal is maintained at a lower signal strength than the analog one, an FM receiver will ignore the digital signal, due to a feature of FM called the "capture effect," wherein a receiver is "captured" by the strongest signal it hears, provided that signal is a particular strength over any other signals. The ratio of the strongest signal to the next strongest that still results in the strongest signal winning is called the "capture ratio."

    Nutshell, therefore, is that this will require no new spectrum, but will inestead make more judicious use of existing spectrum, unlike digital TV.

    One last note, about content. XM and Sirius have the potential to deliver something other than the Clear Channels pablum. That doesn't mean they will, nor does it mean that they will continue to do so if they do in the first place. Broadcast FM, however, and its new digital counterpart, have the potential to continue to deliver community-originated content, where community radio stations exist, such as our own local, WRPI.

  7. Re:4 voting members? on FCC Approves Digital Radio, Kills Satellite Merger · · Score: 1

    They had three only a month ago. I believe there were some resignations and/or retirements or something along those lines.

  8. What they really mean on Effects of the Patriot Act on Librarians · · Score: 2, Interesting

    Usurping and
    Subjugating
    America by
    Providing
    All the
    Tools
    Required to
    Implement
    Orwellian
    Tyranny

  9. Boondoggle on More on GM's New Fuel Cell Cars · · Score: 2, Interesting

    Fuel cells are a boondoggle! All they are is a new way to burn old fuels. Yes, they run on Hydrogen. Where does the hydrogen come from? There are two answers:

    • It is extracted from fossil fuels
    • It is extracted from water

    So what is wrong with this?

    Well, in the first case, you produce a lot of carbon dioxide, and worse, carbon monoxide, in the extraction process. At least the extraction process is energy self-sufficient, i.e. it gets all the energy it needs from the fuel being extracted.

    Extracting hydrogen from water, on the other hand, you get out the same amount of energy that you put in, minus losses. As such, it is not a way to produce energy, only to store it. So where does the electricity come from with which to do this?

    Fuel cells are an interesting technology, but they do not come anywhere near offering a solution to any energy production problem that we are likely to face.

  10. Re:Question: CD-quality VoIP on Internet Phones Replacing POTS In Japan · · Score: 1

    Under an all-analog telephone network, calls between phones switched by the same CO, and not fed via a concentrator, all sounded excellent. Bandwidth was only limited by the capacitance/inductance of the telephone line itself, and the bandwidth of the phones on either end of the line.



    This remained true after the networks started migrating to a digital format, as the trunk lines became digital, but the switches were still analog.



    Analog trunk lines, however, were another story. Whenever a call got shuttled between CO's, it would be upper-sideband modulated onto carriers that were spaced 4000Hz apart. The practical effect of this is that the frequency of all of the sounds making up the phone call would be increased by n*4000 Hz; a 500Hz tone in a phone call on channel 3 of the trunk would be transmitted as a 12500Hz tone (3*4000+500). On channel 2, it would ba an 8500Hz tone, on channel 1, a 4500Hz tone, and on channel 0, a 500Hz tone.



    In order that the different phone calls going down a given trunk did not interfere with one another, filtering was put into place. This filtering would roll off any sounds above 3700Hz and below 300Hz in frequency before modulating. This gave the trunk line a 600Hz guard band between concurrent calls.



    As the system transitioned to digital, the low-pass filtering was kept in place in most cases (exception: AT&T True Voice) in order to minimize the incursion of a 60Hz signal from power lines. This also wiped out the next three harmonics (120Hz, 180Hz, 240Hz) and decimated the fifth harmonic (300Hz) of power line interference. (the exceptions would be using a comb filter instead of a low-pass) 8000 samples per second at 7 bits per sample was deemed adequate to match the sound quality of the analog network. This gives us a 56kb/s PCM stream. u-law (logarithmic) encoding is used to improve the dynamic range.



    When the digital transition was completed, by replacing the crossbar switches with digital switches, the sound quality on local calls was decimated to the level of an inter-CO call. I remember this transition taking place in my town in 1993.



    On wireless phones, another matter comes into play. More audio bandwidth requires more RF bandwidth.



    On an analog phone, the bandwidth given is 30kHz of RF. The mode used is FM, which has two parameters which affect bandwidth: highest audio frequency and deviation. Deviation is how far off of center the carrier signal is allowed to move (moving the carrier's frequency is how you put audio on the signal--FM = Frequency Modulation). The minimum bandwidth of an FM signal is twice the sum of the deviation and the highest signal frequency. Raising the deviation improves the dynamic range; raising the highest signal frequency raises the frequency response.



    Given that, the obvious answer is that we want to set the deviation at about 11kHz. Unfortunately, this isn't the correct answer. The deviation is 5kHz, as it is on most two-way FM radios.



    So why the extra bandwidth? Simple. The space above 4kHz is used for signalling. If you were to tune in an analog cellular conversation on a scanner (don't do this, it is illegal!), you would hear a whistling sound above the conversation. That whistling sound is a data carrier. It is used to implement hand-offs, where the phone is switched from one cell to another, along with call ID, phone dialing (cell phones don't use DTMF to dial) etc.



    On digital cell phones, this is simplified. Here, the bandwidth is depenendent on how much you want to compress the audio. The information that would be on the data carrier of an analog cell phone is instead nestled between the packets of compressed voice on the digital voice stream.



    Going back to land lines again, if you have access to the digital nature of the network, and can supply your own codecs on both ends of the line, you can do a thing called switched-56. Radio stations use these to do remotes. Compression such as MP3 can be used, in a 56kb/s stream, to provide a high-quality (not CD quality, but not bad) audio stream over the telephone network.



    I hope this answers your question?


  11. The solution on The Day The Music Died: Windows Media and DRM · · Score: 1

    It's called CDEX, people! Get it! It rips to the fully-standard MP3 format or even the Open-source Ogg Vorbis format. No DRM-BS. Get it! Use it! Love it!

  12. An alternative on Diamonds - Are They Really Worth the Cost? · · Score: 1

    For an engagement ring, I gave my wife a gold ring with three stones on it: an amethyst, a sapphire and a citrine. She feels much the same was as I do about diamonds, and refuses to wear them. She and I have been married for four years now.

  13. Gotta say it.... on Which DVD Recordable Format Will Win? · · Score: 1

    chmod dvd+rwx

  14. Re:How do they do it now? on IMAX Develops Movie Transfer Technology · · Score: 1

    That was my sense on it. I think that the digital transfer must be to improve the resolution somehow....?

    As for the difference, a film show in 35mm uses a frame that is 24mm X 18mm (11mm are lost in the film width for soundtrack, sound sync and sprocket holes). Note the 4:3 ratio. This is then projected through an anamorphic lens, which elongates the picture out to the 16:9 aspect ratio.

    IMAX uses 70mm film stock rather than 35mm. The file is run horizontally, rather than vertically, and the aspect ratio is much wider (don't know exactly what), and unlike the 35mm film, the IMAX image is uncompressed, hence, no anamorphic lens is used to expand it. I want to say that it is 136mm X 62mm or something like that. This significantly larger print area improves the resolution.

    But, as you say, you can't shine shit. I'm not sure how you can make a 35mm negative into a worthy IMAX print.

  15. Re:You want HP to do what? on Perens Backs Down from DMCA Violation · · Score: 1

    Okay, so now HP has pissed off a bunch of geeks (us) who would have liked to see this happen. So, in response, let us not buy HP products. For that matter, we should tell them so.

  16. The boss's name on Review: Men In Black II · · Score: 4, Informative

    The Boss's name is ZED , not Sid. That's zed as in the last letter of the alphabet in all English-speaking nations except the U.S., where, for some unkonwn reason, we call it zee

  17. Re:Do Not Call lists on Telemarketers and Cell Phones? · · Score: 1

    Cell phones have certain particular exchanges. What exchanges these are vary from area code to area code, but it is not difficult to look up an area code and exchange combination (these are called NPANXX's in telco lingo) on the web, see that it belongs or does not belong to a cellular provider and verify the callee's claim.

    As an example, here in area code 518, all phones that begin with 200, 209, 229 and 331, amongst others, are Sprint PCS mobiles. Similarly, all 518-365 numbers are NEXTEL mobiles, and all 518-451 numbers are Cingular mobiles. This list is not exhaustive, BTW, and there are a ton of other exchanges.

  18. Re:Has anyone tried TeleZapper? on Telemarketers and Cell Phones? · · Score: 1

    I think the SIT tones refers to the three consecutive tones, is that right?

    Yes, that's right. There are four variations on the SIT. For a "Customer Irregularity" (this is called the IC tone), It's 913.8Hz for 274ms, 1370.6Hz for 274ms and 1776.7Hz for 380ms.

    There are other variations:

    No circuit/Emergency (NC) is 985.2Hz for 380ms, 1428.5Hz for 380ms, 1776.7Hz for 380ms.

    Variant Code (VC) is 985.2Hz for 380ms, 1370.6Hz for 274ms, 1776.7Hz for 380ms. I don't have any info on what this one is used for.

    Equipment irregularity (RO) is 913.8Hz for 274ms, 1428.5Hz for 380ms, 1776.7Hz for 380ms.

  19. Re:DSL on Cable Firms Limit Users' Freedoms · · Score: 1

    Telocity did have different rules, I don't know if DirecTV (who took over Telocity) still do. What I do know is that, some two or three years ago, I went 'round and 'round with Verizon and Telocity trying to get it hooked up, to no avail (I believe it to be Verizon's fault). Overall, I allowed them 163 days (with multiple extensions of a deadline) before I gave up and got Road Runner. Since then, I have taken great delight in telling folks offering me Verizon sales pitches to get lost.

    Of course, Telocity's understanding with the customer was that you get 640k inbound and 128k outbound, and that was it. Since it wasn't shared, it didn't have that much of a serious impact on anything if you did run a server or a NAT router.

    I don't know how they would have felt about WAP's, though. I can't help but think that they would have a somewhat negative view, because, even though you would be losing some of your own bandwidth (at no cost to anyone else), you might be inadvertently persuading another user not to get DSL because they have you.

    Yes, I know the DSL bandwidth aggregates somewhere and that you might put extra load there, blah, blah, blah. Telocity just didn't present that kind of a face to the customer, as though they really didn't care about that part.

  20. Re:Why is he a free man? on Mitnick Testifies on Telco's Security · · Score: 0

    So what have you got, you anonymous piece of shit? Show me your "skillz", or are you just another script kiddie with an attitude?

  21. Re:What's the '?' for... on Mitnick Testifies on Telco's Security · · Score: 1

    Mitnick is a convicted criminal. That is a fact.

    Far more criminal than anything he's done, though, is the fact that he spent so much time behind bars without a trial. So much for a fair and speedy trial....

  22. Two cool things I had on Subversive Gifts for New College Students? · · Score: 1

    1. A scanner. I don't mean a paper scanner, I mean a scanning radio receiver. You could hear all kinds of cool s*** listening to the large number of cordless phones in the dorms.... Not to mention listening in on the campus cops.

    2. A short-range FM Radio transmitter. I had the Ramsey FM-10 (go to Ramsey Electronics for details). You want one for "Part 15" operation. These are legal, not very expensive, and very, very subversive!

    3. I'll echo a sentiment I read in another post.... Lots and lots of encouragement--the single most subversive thing there is.

    Oh, and don't let her get a cordless phone unless it is digital and encrypted, 'cos there are guys like me on campus (See item 1 above. :-D )

  23. I saw a comment here.... on RMS Replies to "The Stallman Factor" · · Score: 1

    I saw a comment here once in someone's sig line that was noteworthy, and applies to the Bitkeeper issue....

    "I use Linux, not because it is free in any sense of the word, but because it is better than Windows." (okay, maybe that isn't the exact quote, but it is pretty close.)

    My apologies to the original poster of this remark, I don't remember who it was.

  24. Re:Contract with the networks on Turner CEO: "PVR Users Are Thieves" · · Score: 3, Interesting

    The usage is not free of charge, in fact, it is rather pricey. They pay a license fee to the FCC, and have to renew every couple of years....

    Now, about this contract..... I didn't sign any contract. I challeng the networks to produce for me the contract I allegedly agreed to, and explain to me through what mechanism I allegedly agreed to this.

    Lastly, how about we put together a contract for the networks. Something along the line of the Software Vendor License Agreement mentioned on /. yesterday?

  25. It's not a hoax. on Apple Deals with Devil, Communists · · Score: 2, Interesting

    It's not a hoax at all. It's terribly sad, but true, that there are people claiming to be Christians out there who are really so paranoid. Print doesn't do it justice. Until you have heard this sort of pablum expressed vocally, you just don't grasp that these guys are dead serious.

    To quote one of their own, however, they're almost there--they can almost see the ridiculousness of their position. In the text, it talks about simulations of evolution on a created machine. Why can't evolution take place in a created universe? Wny are evolution and creationism mutually exclusive? It strikes me as though one answers the question "What happened?" and the other answers the question "How did it happen?"

    Idiocy like this is part of the reason why I am no longer a Christian. I grant that these guys are fringers, but questioning them led to me questioning the whole shooting match, and drawing the conclusion that none of them know what they are talking about, regardless whether or not they are this paranoid.

    This is, of course, my opinion as an agnostic (not to be confused with an atheist). I mean no disrespect to Christians. I subscribe to the Ghandian principle of equality of religion, based on the belief that no mortal can know all about God.