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Re: Would Faraday's original experiments have generated intelligent EM?

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On 9/2/2016 12:41 AM, jpopovaclark@gmail.com wrote:
> On Friday, 2 September 2016 12:51:52 UTC+10, nu...@bid.nes  wrote:
>> On Thursday, September 1, 2016 at 2:31:57 AM UTC-7,
>> jpopov...@gmail.com wrote:
>>> Faraday's initial electricity experiments were in the 1820s and
>>> 30s.  If an alien civilization had exquisite EM detection
>>> sensitivity, excellent understanding of stellar physics (to sort
>>> out stellar noise from an unnatural EM emission) and the ability
>>> to respond immediately, how far away could the first responding
>>> civilization be? Wouldn't the answer be about 90-95 Light years
>>> away?
>>
>> Do you know the term "effective radiated power"? It's the energy
>> per unit time emitted from a specified type of antenna in a
>> particular direction, irrespective of losses in the transmitting
>> system other than antenna inefficiency. To be an antenna worthy of
>> the name, it must be a conductor whose length is either in the
>> neighborhood of the same length as the wavelength of the frequency
>> you want to transmit at (resonant half-wave, full-wave dipole,
>> etc.), or so many multiples long that you can radiate at many
>> frequencies (non-resonant long wire). In either case feeding them
>> is tricky. That's a VERY inadequate description by the way; antenna
>> design very quickly starts to look like Black Magic after you dig
>> into it. Nonetheless, those statements are always true.
>>
>> Faraday never worked with a whole lot of power to begin with, and
>> certainly knew nothing of antenna design and optimization. Worse,
>> he worked exclusively with direct current, so his equipment could
>> only radiate when current was started or stopped within it, in
>> "spikes" of energy, not continuous trains of waves. Plus, had he
>> known that his equipment was radiating and thus "wasting" energy,
>> he'd have tried to STOP it from radiating so he could do what he
>> was actually trying to do.
>>
>> The conductors he used were far too long to serve as resonators for
>> those spikes, and long-wires don't radiate directionally especially
>> when those wires aren't straight and when many long-wires, all with
>> bends and curlicues, are transmitting those spikes such that they
>> interfere with each other. Any directionality would be completely
>> accidental and would change when he changed the experimental
>> setup.
>>
>> So, best case he's transmitting a watt or so per spike,
>> isotropically (the energy radiates in all directions rather than
>> being beamed), and intermittently. His signals, if any, would have
>> similar characteristics to those of distance lightning strikes.
>>
>> Your average cellphone emits up to five watts with an antenna
>> carefully designed to maximize emission, and they're not hard to
>> make directional. Even then their top range is a couple of miles,
>> weather permitting.
>>
>> So no, ETs at any distance had no chance at all to hear Faraday any
>> more than they could have heard the alleged Baghdad battery being
>> hooked up to electroplate metal objects much longer ago.
>>
>>
>> Mark L. Fergerson
>
> Sounds like the answer is "No, the effective power of Faraday's
> accidental yet unnatural EM emissions would be so low that they would
> not be detectable from interstellar distances.  In any case the
> emissions would not be sufficiently unnatural to provide evidence of
> a contactable intelligence."
>
> So that makes an interesting question "when did human EM emissions,
> whether deliberate or no, become sufficiently powerful and unnatural
> to provide proof to an advanced technological intelligence that
> someone down here is capable of listening to a transmission? And
> therefore how far away could a responding civilisation be that we
> could receive a deliberately beamed response?"
>

Rather turn Question around, how far can one receive Earth Signals ?

        easy calculation

https://en.wikipedia.org/wiki/Johnson%E2%80%93Nyquist_noise

noise power, P = 4 * kB * T * deltaF

where kB is Boltxmanns constant, and deltaF is bandwidth

where your signal power exceeds the noise power, you can hear it.

then find freespace loss equation;

https://en.wikipedia.org/wiki/Free-space_path_loss


then assume TV signal, 1 meggawatt, 6MHz bandwidth at 70 Mhz (you can 
plug in real data here )

assume a T, google noise figure or noise factor for it convert to K



         solve for r

then do it for the other signals

or use calculators on line

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Would Faraday's original experiments have generated intelligent EM? jpopovaclark@gmail.com - 2016-09-01 02:31 -0700
  Re: Would Faraday's original experiments have generated intelligent EM? noTthaTguY <abu.kuanysh05@gmail.com> - 2016-09-01 11:20 -0700
  Re: Would Faraday's original experiments have generated intelligent EM? Sergio <invalid@invalid.com> - 2016-09-01 15:01 -0500
  Re: Would Faraday's original experiments have generated intelligent EM? "nuny@bid.nes" <Alien8752@gmail.com> - 2016-09-01 19:51 -0700
    Re: Would Faraday's original experiments have generated intelligent EM? jpopovaclark@gmail.com - 2016-09-01 22:41 -0700
      Re: Would Faraday's original experiments have generated intelligent EM? Sergio <invalid@invalid.com> - 2016-09-02 08:47 -0500
        Re: Would Faraday's original experiments have generated intelligent EM? Sergio <invalid@invalid.com> - 2016-09-02 10:35 -0500
      Re: Would Faraday's original experiments have generated intelligent EM? edprochak@gmail.com - 2016-09-02 09:19 -0700
        Re: Would Faraday's original experiments have generated intelligent EM? jpopovaclark@gmail.com - 2016-09-06 18:28 -0700
    Re: Would Faraday's original experiments have generated intelligent EM? benj <benj@nobody.net> - 2016-09-03 21:31 -0400
      Re: Would Faraday's original experiments have generated intelligent EM? "nuny@bid.nes" <Alien8752@gmail.com> - 2016-09-03 19:58 -0700
        Re: Would Faraday's original experiments have generated intelligent EM? benj <benj@nobody.net> - 2016-09-05 18:07 -0400
          Re: Would Faraday's original experiments have generated intelligent EM? jimp@specsol.spam.sux.com - 2016-09-05 23:59 +0000
            Re: Would Faraday's original experiments have generated intelligent EM? benj <benj@nobody.net> - 2016-09-05 22:26 -0400
              Re: Would Faraday's original experiments have generated intelligent EM? jimp@specsol.spam.sux.com - 2016-09-06 04:56 +0000
          Re: Would Faraday's original experiments have generated intelligent EM? Sergio <invalid@invalid.com> - 2016-09-05 19:16 -0500
          Re: Would Faraday's original experiments have generated intelligent EM? "nuny@bid.nes" <Alien8752@gmail.com> - 2016-09-05 19:46 -0700
            Re: Would Faraday's original experiments have generated intelligent EM? benj <benj@nobody.net> - 2016-09-05 23:34 -0400
          Re: Would Faraday's original experiments have generated intelligent EM? edprochak@gmail.com - 2016-09-06 10:13 -0700

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