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Re: long antenna

From gilber34 <fafa@invalid.com>
Newsgroups sci.physics
Subject Re: long antenna
Date 2015-11-30 20:23 -0600
Organization Aioe.org NNTP Server
Message-ID <n3j0b1$tv8$1@speranza.aioe.org> (permalink)
References (10 earlier) <s0juic-u98.ln1@mail.specsol.com> <n3iajn$ha2$1@speranza.aioe.org> <i0puic-at8.ln1@mail.specsol.com> <n3imr2$dn9$1@speranza.aioe.org> <pe5vic-j4a.ln1@mail.specsol.com>

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On 11/30/2015 6:15 PM, jimp@specsol.spam.sux.com wrote:
> gilber34 <fafa@invalid.com> wrote:
>> On 11/30/2015 2:43 PM, jimp@specsol.spam.sux.com wrote:
>>> gilber34 <fafa@invalid.com> wrote:
>>>> On 11/30/2015 1:01 PM, jimp@specsol.spam.sux.com wrote:
>>>>> gilber34 <fafa@invalid.com> wrote:
>>>>>> On 11/28/2015 4:58 PM, jimp@specsol.spam.sux.com wrote:
>>>>>>> gilber34 <fafa@invalid.com> wrote:
>>>>>>>> On 11/27/2015 10:46 AM, benj wrote:
>>>>>>>>> On 11/27/2015 02:01 AM, gilber34 wrote:
>>>>>>>>>> On 11/26/2015 10:45 PM, benj wrote:
>>>>>>>>>>> On 11/26/2015 08:37 PM, jimp@specsol.spam.sux.com wrote:
>>>>>>>>
>>>>>>>>>
>>>>>>>>> perhaps not gamma ray, but you DO know that X-ray parabolic antennas
>>>>>>>>> exist, right?
>>>>>>>>
>>>>>>>> using glancing, paraboioids and hyperboioids, not quite the same as a
>>>>>>>> dish.  but my point was to counter the over generalization that EM
>>>>>>>> frequency being the same.  Still waiting on the size of the 60 HZ dish
>>>>>>>> for 20 dB gain...
>>>>>>>
>>>>>>> Pretty large, but the physical size is irrelevant; the gain of a dish
>>>>>>> is a function of it's diameter in wavelengths, so the gain of a 3 lambda
>>>>>>> 60 Hz dish is the same as the gain of a 3 lambda 60 GHz dish.
>>>>>>
>>>>>> as usual, WRONG.
>>>>>
>>>>> Nope.
>>>>>
>>>>> Then why do antenna books have nomographs of dB gain verssus physical
>>>>> size with straight lines for frequency.
>>>>
>>>> you should stay away from them, they cause you to over-generalize
>>>
>>> You should look at some and learn something.
>>>
>>>>>
>>>>>> the 60Hz dish would be 17,794,063.6 meters wide or 11,056 miles wide or
>>>>>> 100 times the diameter of the Earth. Impossable to build it at all.
>>>>>
>>>>> Not in space given enough time and money.
>>>>
>>>> infinite time, infinite money, infinite stupidity, it cannot be built in
>>>> space either. (extra credit for why)
>>>
>>> Electromagnetic theory has nothing to do with structural engineering.
>>
>> which EM theory ?  and it is all governed by boundry conditions which is
>> structural, got it ?
>
> There is no boundry condition for frequency, got it?
>

every antenna has a boundry condition on frequency band it operates in, 
GOT IT ?

you have no specifics you just grannie troll.


>
>>>>>
>>>>>> THE PHYSICAL SIZE IS THE ISSUE !
>>>>>
>>>>> Nope.
>>>>>
>>>>> Physical size only determines the econonomic practicably, not the RF
>>>>> characteristics.
>>>>
>>>> Wrong.  In what bands is RF treated as primarly magnetic, treated as EM,
>>>> and then treated as partical ?
>>>
>>> None; you are a babbling idiot.
>>>
>>>>>
>>>>>> (what size waveguide do you feed a 60 Hz dish with ?)
>>>>>
>>>>> You assume due to your utter ignorance of antennas and RF in general
>>>>> that all dishes are fed with waveguide; they are not. It is very
>>>>> common to feed dishes in the lower microwave region and below with
>>>>> coax.
>>>>
>>>> answer the question, what size waveguide do you feed a 60Hz dish with ?
>>>> (since you say RF scales with everything)
>>>
>>> You assume due to your utter ignorance of antennas and RF in general
>>> that all dishes are fed with waveguide; they are not.
>>
>> you said that I did not.
>
> Assumed by your repeated demand for a waveguid size.

Google for it,  you scale everything but waveguide size, why ?

>
>>>
>>> It is very common to feed dishes in the lower microwave region and below
>>> with coax.
>>
>> so what does the FEED HORN look like ? a WAVEGUIDE ?
>
> Yet more ignorance.
>
> You assume due to your utter ignorance of antennas and RF in general
> that all dishes are fed with a feed horn; they are not.
>
> I have a very nice X band dish that is fed with a dipole.

what is the pattern of a dipole ?
you have a cheap splatter dish, not a good focused one.
Your pattern is multilobed with high F/B ratio, and you dont know it.

>
>> Got anything to back you wild ass disperate hand waving up?
>
> Just who is desperately hand waving here?
>
>>> While one COULD construt 60 Hz waveguide in space, doing so would be
>>> stupid.
>>
>> so, although you said it can be done, which I disagree with, you do
>> finally agree with me, after considerable thought, that it is TOTALLY
>> STUPID.
>
> Yes, 60 Hz waveguide is stupid and YOU are the one that brought it up.

....you talked about building one.......  so you don't know you were 
being fooled all along.  60Hz waveguide! silly

>
>>>>>> your max surface roughness at 60GHz is what ?
>>>>>
>>>>> It is perfect because competant people were used to build it and
>>>>> irrelevant to the fact that antennas scale in frequency.
>>>>
>>>> so what is the surface roughness ? use rms
>>>
>>> It is perfect because competant people were used to build it and
>>> irrelevant to the fact that antennas scale in frequency.
>>
>> so what is the number in inches ?  Can't  you figure it out ?
>> All you do is answer in *weazel word* vague statements like grandma
>> Trollie.
>
> Surface roughness has nothing to do with the fact that antennas scale
> in frequency.

wrong, you have never made antennas.

>
>> is it 1/10 of an inch ?   afraid of "guessing", that is all you do.
>
> Surface roughness is measured in wavelenths, not inches.

either, it is interchangeable, but what is surface roughness, you can 
google it, it is ok.

>
>>
>>>
>>>> and again you are wrong, antennas scale over ranges, not infinities.
>>>
>>> Nowhere in any electromagnetic theory will you find anything like
>>> A < frequency < B.
>>
>> wrong again.  perhaps you should read some books first, you are too
>> green to be able to add anything useful here.
>
> So you should be able to point to somewhere that this appears other
> than in your imagination.

you lack common knowledge of the names and areas of EM spectrum, you troll.


>
>> So What is your "electromagnetic theory" ?  can you list a reference ?
>> or the equations ?  you have certianly missapplied them
>
> You might try reading the works of Fraday, Henry, Maxwell, Lorentz,
> Poincare, and Einstein.

you never had a college course.

>
> If you want a specific book, start with "Electromagnetics" by Kraus
> and Carver as it is a standard text on the subject.

gernic

>
>>> You are an ignorant idiot.
>>>
>>>>>
>>>>>> How much beam taper do you illuminate the edges with to avoid backlobes
>>>>>> at 60GHz? which would pick up the 60HZ earth very well. What would the
>>>>>> F/B ratio be to pick up a 60Hz craft 1,000,000,000 miles out ?
>>>>>
>>>>> The same as at 60 GHz.
>>>>
>>>> Totally wrong, one is easy, the other is impossable.
>>>
>>> Nope, just not practically economical to build.
>>
>> wrong again, you really have to give up your idealism, as it is wrong,
>
> What I have is not idealism, it is called an education.
>
>> Answer now, what is the F/B ratio of a 60Hz dish 11,000 miles in diameter ?
>
> How much are you offering for me to do this?

you have 5 min.  Google for it.

>
>>>>
>>>> How thick must your dish be to reflect 60Hz ?
>>>
>>> New flash idiot, the skin effect scales with frequency also.
>>
>> no, it is non linear, pupa.
>
> I did not say it was either linear or non-linear, I said it scales
> with frequency.

when something scales with another, it is linear. everybody knows that, 
except you.

>
>>>> how much beam taper ?
>>>
>>> Irrelevant.
>>
>>>
>>>>>
>>>>>>> The only issue with a dish at gamma or X-ray frquencies is that the
>>>>>>> dish has to be made of a material that is reflective at those frequencies,
>>>>>>
>>>>>> which there are not any for a parabolic dish.
>>>>>
>>>>> Which is irrelevant to the fact that antennas scale in frequency.
>>>>
>>>> Wrong, because you cannot use a parabolic with gamma, so the do not scale.
>>>> wrong, because you over-generalized
>>>
>>> All the laws of electromagnetics says it scales. The fact that there is
>>> no practical material to build one is irrelevant to the theory of
>>> electromagnetics.
>>
>> wrong, you stuck on this wrongness, things scale some, but if not into
>> the real world, the do not scale.
>
> Electromagnetic theory scales.

fish scales.

>
> All half wave dipoles work exactly the same no matter the physical
> size because they are all a half wavelength long.
>
>> Does you parabolic dishes work on atoms ?
>
> Gibberish.

from your "scaling" of your parabolic dishes,
we agree you are gibberish.

>
>>
>> and what is your "laws of electromagnetics" AND "theory of
>>   electromagnetics" ?
>
> Two way of saying the same thing, idiot.

laws are not theory, and you dont know what you are talking about.

>
>> they are just buzzzwords to you, some EM god equation that saves your
>> obviously wrong postings from smelling like poo poo.
>
> Oh, did I hurt your feelings by calling your ignornant nonsense ignorant
> nonsense?

you still offer no content, just argument, no links, just troll

>
>>>
>>>>>
>>>>> If you can find a material that is relective at gamma or X-ray frquencies,
>>>>> then such a dish will perform just the same as any other dish at any
>>>>> other frequency with the same diameter in wavelengths.
>>>>
>>>> "if"  but it dosent, so a parabolic dish will not work, and has no gain.
>>>
>>> All the laws of electromagnetics says it scales. The fact that there is
>>> no practical material to build one is irrelevant to the theory of
>>> electromagnetics.
>>
>> it doesnt work at gamma, nor at 60 Hz, so it does not scale, your so
>
>>
>>
>>>
>>>> Not scalable.
>>>
>>> Yep.
>>>
>>>>>
>>>>>> what is the max surface roughness you could have ? (hint: 1/4 lamda and
>>>>>> how much is that?) can anybody do that yet ?
>>>>>> so you are WRONG again, find the answer in ARRL, not.
>>>>>
>>>>> The requirements would be the same as any other dish at any other frequency
>>>>> with the same diameter in wavelengths.
>>>>
>>>> more foo-foo.  You have not been able to justify your absurd
>>>> over-generalization.
>>>
>>> All the laws of electromagnetics says it scales.
>>
>> every law ? can you list them ?
>
> Idiot.

I am waiting, you cannot find your "All the laws of electromagnetics" 
yet ?  Did you lose them ?  try wiki

>
>>
>>>
>>>> go do that to a bicycle, one can be made at any size and still function...
>>>
>>> The subject is the laws of electromagnetics.
>>
>> no the subject is obvious misuse of scaleability .  A typical problem
>> Physicists have.
>
> Clueless.
>
>>
>>>
>>>>>
>>>>> The thing you are utterly unable to understand is that electromagnetic
>>>>> theory of antennas is frequency independant.
>>>>
>>>> wrong.  antennas are resonate material structures only at certian
>>>> frequiencys.
>>>
>>> Apples and oranges and shows an utter lack of understanding of
>>> electromagnetic theory.
>>>
>>> A yagi antenna has a particular size in WAVELENGTHS. That means that
>>> if the antenna is described in WAVELENGTHS, it works identically
>>> at any frequency.
>>
>> wrong, it works only at that one wavelength, that is why is it called a
>> resonate structure, (and odd harmonics with discrintegrating pattern)
>>
>> it is in your ARRL book, this is kindgarten stuff.
>
> It is in every book on antennas and every book on electromagnetic theory,
> idiot.

and yagis are resonant structures, like dipoles, monopoles, waveguides 
even, the work only in a limited frequency band.


>>
>>>
>>> All half wavelength dipoles work identically because their size is
>>> described in WAVELENGTHS.
>>
>> so where is your 60GHz  1/2 wavelength antenna ?
>> or your 1/2 wavelength 60 Hz antenna ?
>
> Yet more meaningless babble.
>

cant do an equation.

>>>
>>>>>
>>>>> The practical ability to construct a given antenna may change with
>>>>> frequency, but the electromagnetic theory does NOT.
>>>>
>>>> wrong again.
>>>>    EM theory(s) applies differently to different structures, it is not
>>>> one equation governs all. And is driven by boundry conditions, some
>>>> scale, some do not.
>>>
>>> Babbling gibberish.
>>>
>>>>    at times you have to use other means than stright EM to make the
>>>> antenna work, like the capacitive match at a single helix antenna
>>>> reflector, diameter of Yagi elements.
>>>
>>> Babbling gibberish.
>>>
>>>
>>>> take the transmitter, receiver transmission path reciprosity, it can be
>>>> non linear. EM theory says linear.
>>>
>>> Babbling gibberish.
>>>
>>>> here is a link you can study
>>>> https://en.wikipedia.org/wiki/Maxwell's_equations
>>>
>>> And where in there do you see any term that looks like A < freq < B,
>>> you babbling idiot?
>>
>> look again, there are two constants in the equations, perhaps you cannot
>> read, and cannot understand equations.
>
> Utter nonsense.

nothing, you troll.

>
> If such actually existed, you would be gleefully pointing it out and
> crying "see, see!!" but you can't as such does not exist.

https://en.wikipedia.org/wiki/Radio_frequency

look anywhere, you oversimplify, you do not have experience, you troll.

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Thread

long antenna RichD <r_delaney2001@yahoo.com> - 2015-11-17 10:42 -0800
  Re: long antenna Odd Bodkin <bodkinodd@gmail.com> - 2015-11-17 12:46 -0600
    Re: long antenna Poutnik <poutnik4nntp@gmail.com> - 2015-11-17 20:10 +0100
    Re: long antenna jimp@specsol.spam.sux.com - 2015-11-17 20:28 +0000
      Re: long antenna benj <nobody@gmail.com> - 2015-11-17 16:59 -0500
    Re: long antenna Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-11-18 22:56 +0100
      Re: long antenna gilber34 <fafa@invalid.com> - 2015-11-18 16:57 -0600
        Re: long antenna jimp@specsol.spam.sux.com - 2015-11-18 23:15 +0000
          Re: long antenna gilber34 <fafa@invalid.com> - 2015-11-18 20:42 -0600
            Re: long antenna jimp@specsol.spam.sux.com - 2015-11-19 05:29 +0000
              Re: long antenna gilber34 <fafa@invalid.com> - 2015-11-19 08:54 -0600
                Re: long antenna jimp@specsol.spam.sux.com - 2015-11-19 18:44 +0000
                Re: long antenna gilber34 <fafa@invalid.com> - 2015-11-22 15:32 -0600
                Re: long antenna jimp@specsol.spam.sux.com - 2015-11-22 23:16 +0000
            Re: long antenna HVAC <mr.hvac@gmail.com> - 2015-11-19 06:59 -0800
              Re: long antenna benj <none@gmail.com> - 2015-11-19 20:02 -0500
      Re: long antenna benj <none@gmail.com> - 2015-11-19 01:36 -0500
  Re: long antenna gilber34 <fafa@invalid.com> - 2015-11-17 13:28 -0600
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      Re: long antenna benj <nobody@gmail.com> - 2015-11-17 19:28 -0500
        Re: long antenna Timo <timo@physics.uq.edu.au> - 2015-11-17 17:18 -0800
          Re: long antenna RichD <r_delaney2001@yahoo.com> - 2015-11-24 11:39 -0800
            Re: long antenna benj <none@gmail.com> - 2015-11-24 15:12 -0500
              Re: long antenna gilber34 <fafa@invalid.com> - 2015-11-26 09:21 -0600
                Re: long antenna gilber34 <fafa@invalid.com> - 2015-11-26 10:05 -0600
                Re: long antenna jimp@specsol.spam.sux.com - 2015-11-26 20:05 +0000
                Re: long antenna gilber34 <fafa@invalid.com> - 2015-11-26 18:39 -0600
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            Re: long antenna jimp@specsol.spam.sux.com - 2015-11-24 20:04 +0000
              Re: long antenna gilber34 <fafa@invalid.com> - 2015-11-24 16:33 -0600
                Re: long antenna jimp@specsol.spam.sux.com - 2015-11-24 22:58 +0000
                Re: long antenna gilber34 <fafa@invalid.com> - 2015-11-26 09:11 -0600
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                Re: long antenna "Ross A. Finlayson" <ross.finlayson@gmail.com> - 2015-11-26 11:57 -0800
                Re: long antenna gilber34 <fafa@invalid.com> - 2015-11-26 14:52 -0600
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                Re: long antenna gilber34 <fafa@invalid.com> - 2015-11-26 18:58 -0600
                Re: long antenna jimp@specsol.spam.sux.com - 2015-11-27 01:37 +0000
                Re: long antenna benj <none@gmail.com> - 2015-11-26 23:45 -0500
                Re: long antenna gilber34 <fafa@invalid.com> - 2015-11-27 01:01 -0600
                Re: long antenna "Ross A. Finlayson" <ross.finlayson@gmail.com> - 2015-11-26 23:31 -0800
                Re: long antenna benj <nobody@gmail.com> - 2015-11-27 11:34 -0500
                Re: long antenna "Ross A. Finlayson" <ross.finlayson@gmail.com> - 2015-11-27 09:58 -0800
                Re: long antenna benj <nobody@gmail.com> - 2015-11-27 11:46 -0500
                Re: long antenna gilber34 <fafa@invalid.com> - 2015-11-28 16:42 -0600
                Re: long antenna jimp@specsol.spam.sux.com - 2015-11-28 22:58 +0000
                Re: long antenna gilber34 <fafa@invalid.com> - 2015-11-30 07:46 -0600
                Re: long antenna jimp@specsol.spam.sux.com - 2015-11-30 19:01 +0000
                Re: long antenna gilber34 <fafa@invalid.com> - 2015-11-30 14:12 -0600
                Re: long antenna jimp@specsol.spam.sux.com - 2015-11-30 20:43 +0000
                Re: long antenna gilber34 <fafa@invalid.com> - 2015-11-30 17:41 -0600
                Re: long antenna jimp@specsol.spam.sux.com - 2015-12-01 00:15 +0000
                Re: long antenna gilber34 <fafa@invalid.com> - 2015-11-30 20:23 -0600
                Re: long antenna jimp@specsol.spam.sux.com - 2015-12-01 06:21 +0000
                Re: long antenna benj <none@gmail.com> - 2015-11-30 15:22 -0500
                Re: long antenna jimp@specsol.spam.sux.com - 2015-11-30 20:48 +0000
                Re: long antenna gilber34 <fafa@invalid.com> - 2015-11-30 17:16 -0600
                Re: long antenna jimp@specsol.spam.sux.com - 2015-11-30 23:52 +0000
                Re: long antenna gilber34 <fafa@invalid.com> - 2015-11-30 19:59 -0600
                Re: long antenna jimp@specsol.spam.sux.com - 2015-12-01 02:16 +0000
                Re: long antenna benj <none@gmail.com> - 2015-11-30 19:20 -0500
                Re: long antenna jimp@specsol.spam.sux.com - 2015-11-27 18:53 +0000
              Re: long antenna benj <none@gmail.com> - 2015-11-25 00:08 -0500
                Re: long antenna jimp@specsol.spam.sux.com - 2015-11-25 06:13 +0000
  Re: long antenna "reber g=emc^2" <herbertglazier0@gmail.com> - 2015-11-18 16:25 -0800
  Re: long antenna "reber g=emc^2" <herbertglazier0@gmail.com> - 2015-11-19 16:08 -0800
    Re: long antenna jimp@specsol.spam.sux.com - 2015-11-20 00:40 +0000
      Re: long antenna "reber g=emc^2" <herbertglazier0@gmail.com> - 2015-11-20 15:51 -0800
        Re: long antenna jimp@specsol.spam.sux.com - 2015-11-21 00:34 +0000
          Re: long antenna jmfbahciv <See.above@aol.com> - 2015-11-21 14:37 +0000
            Re: long antenna jimp@specsol.spam.sux.com - 2015-11-21 19:32 +0000
              Re: long antenna jmfbahciv <See.above@aol.com> - 2015-11-22 14:50 +0000
                Re: long antenna "reber g=emc^2" <herbertglazier0@gmail.com> - 2015-11-22 11:27 -0800
                Re: long antenna jimp@specsol.spam.sux.com - 2015-11-22 19:44 +0000
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                Re: long antenna jmfbahciv <See.above@aol.com> - 2015-11-23 14:13 +0000
                Re: long antenna benj <none@gmail.com> - 2015-11-23 13:00 -0500
                Re: long antenna jmfbahciv <See.above@aol.com> - 2015-11-24 13:20 +0000
                Re: long antenna benj <none@gmail.com> - 2015-11-24 13:40 -0500
                Re: long antenna jmfbahciv <See.above@aol.com> - 2015-11-25 13:44 +0000
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                Re: long antenna jimp@specsol.spam.sux.com - 2015-11-24 19:49 +0000
                Re: long antenna gilber34 <fafa@invalid.com> - 2015-11-24 16:36 -0600
                Re: long antenna jimp@specsol.spam.sux.com - 2015-11-24 23:00 +0000
                Re: long antenna gilber34 <fafa@invalid.com> - 2015-11-26 16:17 -0600
                Re: long antenna jimp@specsol.spam.sux.com - 2015-11-26 23:35 +0000
        Re: long antenna benj <none@gmail.com> - 2015-11-20 20:58 -0500
    Re: long antenna benj <none@gmail.com> - 2015-11-19 20:09 -0500
  Re: long antenna "nuny@bid.nes" <Alien8752@gmail.com> - 2015-11-24 12:51 -0800
    Re: long antenna benj <none@gmail.com> - 2015-11-25 00:01 -0500
  Re: long antenna "reber g=emc^2" <herbertglazier0@gmail.com> - 2015-11-25 15:36 -0800
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