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

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On 9/2/2016 8:47 AM, Sergio wrote:
> 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
>
>
>

pathloss in light years here
http://www.qsl.net/pa2ohh/jsffield.htm

assume aliens have +10 db gain antenna and earth antenna gain is 1db
assume it is at .5 MHz for Faraday

your path loss for 1 light year is -274.9 dB

for 500 MHz the path loss is -334.9 dB


how about receive noise power?
assume a temp of -200 C with LNA
assume recieve bandwidth of 1 HZ  (morse code, has problems)
and assume a resistance of 300 ohms

noise power is -179 dBv

http://www.daycounter.com/Calculators/Thermal-Noise-Calculator.phtml


so to get the signal over the path loss you need 334 - 179 = 155 dB 
transmitted in a 1 hz BW on earth at 1/2 MHz

anyone spot the error ?   need to change dBv to dbw

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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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