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Re: long antenna

From jimp@specsol.spam.sux.com
Newsgroups sci.physics
Subject Re: long antenna
Date 2015-12-01 00:15 +0000
Organization A noiseless patient Spider
Message-ID <pe5vic-j4a.ln1@mail.specsol.com> (permalink)
References (9 earlier) <n3hjv2$kku$1@speranza.aioe.org> <s0juic-u98.ln1@mail.specsol.com> <n3iajn$ha2$1@speranza.aioe.org> <i0puic-at8.ln1@mail.specsol.com> <n3imr2$dn9$1@speranza.aioe.org>

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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?


>>>>
>>>>> 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.

>>
>> 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.
 
> 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.

>>>>> 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.

> is it 1/10 of an inch ?   afraid of "guessing", that is all you do.

Surface roughness is measured in wavelenths, not inches.

> 
>>
>>> 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.

> 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.

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

>> 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?

>>>
>>> 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.

>>> 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.

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.

> 
> and what is your "laws of electromagnetics" AND "theory of
>  electromagnetics" ?

Two way of saying the same thing, idiot.

> 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?

>>
>>>>
>>>> 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.

> 
>>
>>> 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.
> 
>>
>> 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.

>>
>>>>
>>>> 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.

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

 

-- 
Jim Pennino

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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
  Re: long antenna "reber g=emc^2" <herbertglazier0@gmail.com> - 2015-11-17 14:04 -0800
    Re: long antenna jimp@specsol.spam.sux.com - 2015-11-17 22:35 +0000
      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
                Re: long antenna jimp@specsol.spam.sux.com - 2015-11-27 01:46 +0000
                Re: long antenna jimp@specsol.spam.sux.com - 2015-11-26 19:55 +0000
            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
                Re: long antenna jimp@specsol.spam.sux.com - 2015-11-26 19:42 +0000
                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
                Re: long antenna jimp@specsol.spam.sux.com - 2015-11-26 21:12 +0000
                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
                Re: long antenna jimp@specsol.spam.sux.com - 2015-11-22 19:40 +0000
                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
                Re: long antenna jimp@specsol.spam.sux.com - 2015-11-23 18:47 +0000
                Re: long antenna jmfbahciv <See.above@aol.com> - 2015-11-24 13:20 +0000
                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
    Re: long antenna jimp@specsol.spam.sux.com - 2015-11-25 23:51 +0000

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