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Comments · 478

  1. Gas tax, NOTHING, property taxes. on Sen. McCain Introduces Bill to Ban Internet Taxes Forever · · Score: 1

    > We need taxes to support things like the highway system,

    What the heck are gas taxes for?

    > public transportation,

    Nope! Let the riders pay their fair share.

    > and public education.

    That is what property taxes are for. It keeps responsibility local, instead of in the Federal
    Government, which wants to use our schools for socialist indoctrination camps.

  2. Worthless fluff from Political American on I Am Not Doctor Strangelove · · Score: 1

    How many lines were quotes from the interview, and
    how many were ramblings of the author? I used to
    find Scientific American interesting, but this is
    just another example of fluff wrapped around the
    barest hint of an interview.

  3. 25% more efficient? That is meaningless by itself on Fractal Antennas more efficient? · · Score: 4

    An antenna radiates some (or most) of its energy, and sends the rest back toward the radio. This ratio is what we call SWR. Of the returned energy, some might be lost in the feedline. The rest reaches the radio and bouces back to the antenna for "another try".

    If we have feedlines that are relatively long for the frequency, we get concerned about the SWR so that our energy is not wasted heating up the coax between the radio and the antenna. If our feedline is short, then the SWR is a factor if it raises the voltage high enough that the reflected energy bothers the radio. That can be really exciting if you are looking at hundreds of watts, but should not be a factor with the low power levels we are contemplating here.

    So if our feedline is short enough, as is common with handheld radios (and cellular phones are radios, of course), our antenna is going to be radiating nearly 100% of the power. It is like the "efficiency" of an electric heater - an electric heater is ALWAYS 100% efficient.

    Perhaps the authors really mean that their antennas can direct the radio energy in a more useful direction, such as horizontally. Often this is exactly what we want, and we already have antennas made just for this (such as a vertical dipole). If this is what they are getting at, I did not see this in their report.