Re: long antenna

From	gilber34 <fafa@invalid.com>
Newsgroups	sci.physics
Subject	Re: long antenna
Date	2015-11-26 18:58 -0600
Organization	Aioe.org NNTP Server
Message-ID	<n389sn$8v6$1@speranza.aioe.org> (permalink)
References	(7 earlier) <6l6fic-59f.ln1@mail.specsol.com> <n377fg$5f6$1@speranza.aioe.org> <ru3kic-ul2.ln1@mail.specsol.com> <n37rf3$12p$1@speranza.aioe.org> <l69kic-a73.ln1@mail.specsol.com>

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On 11/26/2015 3:12 PM, jimp@specsol.spam.sux.com wrote:
> gilber34 <fafa@invalid.com> wrote:
>> On 11/26/2015 1:42 PM, jimp@specsol.spam.sux.com wrote:
>>> gilber34 <fafa@invalid.com> wrote:
>>>> On 11/24/2015 4:58 PM, jimp@specsol.spam.sux.com wrote:
>>>>> gilber34 <fafa@invalid.com> wrote:
>>>>>> On 11/24/2015 2:04 PM, jimp@specsol.spam.sux.com wrote:
>>>>>>> RichD <r_delaney2001@yahoo.com> wrote:
>>>>>>>> On November 17, Timo wrote:
>>>>>>>>>> The idea that making an antenna longer makes it work better comes from
>>>>>>>>>> AM radios and car whips where the antenna is much much shorter than
>>>>>>>>>> wavelength and in that case making it longer often DOES make it work
>>>>>>>>>> better.
>>>>>>>>>
>>>>>>>>> It can help, even when the antenna is larger than the wavelength:
>>>>>>>>> https://en.wikipedia.org/wiki/Arecibo_Observatory
>>>>>>>>
>>>>>>>> Comparing dish vs. wire antenna, is apples vs. oranges.
>>>>>>
>>>>>>>>> But typically one wants to pay more attention to design than just
>>>>>>>>> "long extension wire".
>>>>>>>>
>>>>>>>> More dish area will collect more signal power, but
>>>>>>>> apparently this doesn't apply to a wire.
>>>>>>>
>>>>>>> A dish doesn't collect anything, it concentrates energy to a point.
>>>>>>>
>>>>>>
>>>>>> wrong again.
>>>>>>
>>>>>> a dish is a reflector which changes signal phase over an area, where it
>>>>>> adds in phase is called the focus.
>>>>>
>>>>> And the focal point is where the energy is concentrated.
>>>>
>>>> wrong, it is where the signals add in phase.
>>>
>>> What is the energy density in the region of the focus with no reflector?
>>>
>>> What is the energy density in the region of the focus with a reflector?
>>
>> you ask for energy density w/wo reflector.  you can find that on google.
>
> Nope. It depends on the ERP of the transmitting station and the propagation
> characteristics between the two points.

you over complicate it, no need for transmitting station foo foo or 
probagation losses bla bla.

Hint: What is energy density "ratio", w/wo reflector.  (assume dipole if 
you must)

>
> Normalize it for analysis, if you know what that means.
>
>> What size and type of reflector ?
>
> Any size and any type; pick one.

again you forget frequency,
Frequency 60 Hz, reflector=dish, gain 20 DBi,
you calculate Dish size

>
>> what shape is the reflector required to have and why ?
>
> Any rational shape you desire.

no! shape parabolic, go study equations, they are not hard, I cannot do 
this for you.

>
>> in terms of signal travel time or phase ?
>

>
>> Did you know you can make a flat C band "reflector" out of different
>> length beer cans ?  All the cans do is reflect and change the phase do
>> to length.
>
> It is not a reflector, it is a horn.

not a horn, again you eyes play tricks on you brain.
the reflector is made up of about 200 beer cans, attached together and 
mostly flat, like a freznel lens. Cans are cut to length for the phase 
change needed. but this is beyond your experience, sorry.

>
> FYI people have been making horn feeds from various cans for well over
> 60 years now.

feed horns, not reflectors.   I had a modified paint can feed horn tuned 
to 1.4 to 1.6 GHz with a VSWR of 1.05 a long time ago.

>
>>> https://en.wikipedia.org/wiki/Parabolic_antenna
>>>
>>> Again, get a copy of the ARRL handbook and read it.
>>
>> no need to.
>
>
> You didn't read the Wiki link either, did you, or you wouldn't have
> posted the babbling gibberish below.

wiki worse than amatuer ARRL.

>
>>>
>>>> you thinking magnifying lens as in optics,
>>>>    like when you were burning ants on sidewalk
>>>>
>>>> it is not that way in RF or Microwave.
>>>
>>> Light, RF, and microwave are ALL electromagnetic radiation.

>> the solutions are vastly different in the bands. Gamma?  X-ray ?
>> Parabolic antennas are phase changers, from 700MHz to 40GHz.
>> does your parabolic work on gamma ? or 200GHz ?
>
> Babbling gibberish.
>
> Whether of not a parabolic antenna works or not is purely a function
> of it's size in wavelengths.

wrong again, how do you make it work on Gamma rays ?  or x-rays ?
or 60 Hz ?

try to be specific and provide answers, instead of the red herring 
clue-less bone throwing

>
>
>
>>>>>> "concentrate" is what they do to Orange Juice.
>>>>>
>>>>> concentrate verb

>>>>> to bring or come together in a large number or amount in one particular
>>>>> area

>>>>> Again, get a copy of the ARRL handbook and stop being so ignorant.
>>>>
>>>> you base you knowledge on an out of date, stale, amateurish, Amateur
>>>> Radio book
>>>
>>> Nope, but if YOU were to read the 2015 edition, you might lose some
>>> of your ignorance about the basics of RF, such as light and microwaves
>>> being different and what a reflector in an antenna system does.
>>
>> forget ARRL, that is kindagarden,
>
> Then you must be pre-school.
>
>>   move to "Antennas" by Kraus immediatly, then read "Antennas for all
>> Applications" by Kraus, then read "Radio Astronomy" by Kraus
>> seems like some should be online, public domain stuff.
>
> I actually have a job and buy books.

ok, you got Kraus in you libarary ? (any of them?)

>
>> and they have all the  equations to design your own.
>
> I've been designing antennas that actually work for about about 50
> years now.

they are fun to design and make, I did a tribander for police car in UHF 
and 800 MHz bands.  but uW are more fun.

ever see the insides of the dome of the Omnitracs system ? clever design 
there. (trucking industry, communicates and gets location from 
stattilites, qualcomm in SD)

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
  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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