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Re: Coaxial cable calculation

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On 4/10/2018 5:24 PM, Trevor Wilson wrote:
> On 11/04/2018 8:18 AM, Sergio wrote:
>> On 4/10/2018 3:03 PM, benj wrote:
>>> On 4/10/2018 12:44 PM, Sergio wrote:
>>>> On 4/10/2018 11:32 AM, Lofty Goat wrote:
>>>>> On Tue, 10 Apr 2018 18:21:42 +0200 (GMT+02:00), Libor Striz
>>>>> <poutnik4REMOVEnntp@CAPITALSgmail.com> wrote:
>>>>>
>>>>>> Sergio <invalid@invalid.com> Wrote in message:
>>>>>>> On 4/10/2018 1:42 AM, Trevor Wilson wrote:
>>>>>>>> Here's a question that stumped me back in the old slide rule days:
>>>>>>>>
>>>>>>>> A coaxial cable, having an inner diameter of 0.0254mm (0.001") and
>>>>>>>> using
>>>>>>>> an insulator with a dielectric constant of 2.56, is yo have a
>>>>>>>> characteristic impedance of 2,000 Ohms. What must be the outer
>>>>>>>> conductor
>>>>>>>> diameter?
>>>>>>>>
>>>>>>>> You guys can locate the appropriate method of calculation.
>>>>>>>>
>>>>>>>>
>>>>>>>
>>>>>>> your question is malformed.
>>>>>>>
>>>>>>>    what is yo ?   don't  you mean Zo, which is normally used for
>>>>>>> characteristic impedance of coaxial cables ?
>>>>>>>
>>>>>>> what frequency or frequency band ?
>>>>>>>
>>>>>>>
>>>>>> Yo must mean you...
>>>>>
>>>>> Arcane symbol for admittance, the reciprocal of impedance.  Modern
>>>>> texts
>>>>> use sigma instead.
>>>>>
>>>>
>>>> double checking, usually that is Yo, and measured in siemens, not ohms.
>>>>
>>>> so still need a clarification Trevor, do you mean Yo 2000 siemens or Zo
>>>> 2000 Ohms ?
>>>>
>>>> and frequency band too, (there are places coax won't work)
>>>>
>>> Look at the science deniers squirm as they try to deny this typo!
>>> Clearly Yo is NOT admittance, since Trevor himself say "is yo have a
>>> characteristic impedance of 2,000 Ohms" He clearly used the word
>>> "impedance" not "admittance". Anyway if anyone here knew any actual
>>> practical science you'd know that a Zo of 1/2000 ohms gives a coax of
>>> ridiculous dimensions. Won't find one on your TV I'm sure.
>>>
>>> TREVOR MADE A TYPO and that proves he's uneducated, ignorant and insane!
>>> Neener, Neener, Neener!
>>>
>>
>> Initially I thought he meant "yo" like the urban "you", but that would
>> be a misspelling, and he would not recognize a misspelled word.
>>
>> at least he posted some physics/science stuff in here, so He gets a B.
>>
>> also, when did calculators replace slide rules, in college ?
> 
> **For me, I purchased my first scientific calculator sometime around
> 1973. It cost me AUS$104.00. A huge sum for a student back then. I could
> not afford the superior, Texas Instruments one. I still have my
> favourite slide rule though. A Faber-Castell 2/83N Novo-Duplex. Best
> slide rule ever made.
> 

sounds right, those first calculators were pricy, and did not do that
much, I think I paid about the same for first or second TI.
a few years later HP had some programmable calculators with cards, and
modules we used on the job, lots of complex # calculations, very pricy
too.  Mainframe time was too expensive back then.  and we used Pickett
slide rules, trying to get 3 decimal accuracy on them!

and they called the engineers on campus "Lizards", because they had
slide rule cases attached to their belts

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Coaxial cable calculation Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au> - 2018-04-10 16:42 +1000
  Re: Coaxial cable calculation benj <benj@nobody.net> - 2018-04-10 05:20 -0400
    Re: Coaxial cable calculation Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au> - 2018-04-10 19:33 +1000
      Re: Coaxial cable calculation benj <benj@nobody.net> - 2018-04-10 15:28 -0400
        Re: Coaxial cable calculation Sergio <invalid@invalid.com> - 2018-04-11 08:36 -0500
          Re: Coaxial cable calculation benj <benj@nobody.net> - 2018-04-11 14:38 -0400
            Re: Coaxial cable calculation Sergio <invalid@invalid.com> - 2018-04-11 13:55 -0500
      Re: Coaxial cable calculation benj <benj@nobody.net> - 2018-04-10 15:45 -0400
    Re: Coaxial cable calculation Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> - 2018-04-10 12:24 +0200
      Re: Coaxial cable calculation benj <benj@nobody.net> - 2018-04-10 15:37 -0400
  Re: Coaxial cable calculation Sergio <invalid@invalid.com> - 2018-04-10 10:59 -0500
    Re: Coaxial cable calculation Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> - 2018-04-10 18:21 +0200
      Re: Coaxial cable calculation Lofty Goat <rlwatkins@gmail.com> - 2018-04-10 11:32 -0500
        Re: Coaxial cable calculation Sergio <invalid@invalid.com> - 2018-04-10 11:44 -0500
          Re: Coaxial cable calculation benj <benj@nobody.net> - 2018-04-10 16:03 -0400
            Re: Coaxial cable calculation Sergio <invalid@invalid.com> - 2018-04-10 17:18 -0500
              Re: Coaxial cable calculation Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au> - 2018-04-11 08:24 +1000
                Re: Coaxial cable calculation Sergio <invalid@invalid.com> - 2018-04-10 17:38 -0500
                Re: Coaxial cable calculation Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au> - 2018-04-11 08:42 +1000
                Re: Coaxial cable calculation benj <benj@nobody.net> - 2018-04-11 07:36 -0400
                Re: Coaxial cable calculation Sergio <invalid@invalid.com> - 2018-04-11 08:38 -0500
                Re: Coaxial cable calculation Lofty Goat <rlwatkins@gmail.com> - 2018-04-11 21:57 -0500
              Re: Coaxial cable calculation benj <benj@nobody.net> - 2018-04-11 07:23 -0400
                Re: Coaxial cable calculation Sergio <invalid@invalid.com> - 2018-04-11 08:39 -0500
                Re: Coaxial cable calculation Sergio <invalid@invalid.com> - 2018-04-11 11:20 -0500
    Re: Coaxial cable calculation Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au> - 2018-04-11 05:48 +1000
      Re: Coaxial cable calculation benj <benj@nobody.net> - 2018-04-10 16:10 -0400
      Re: Coaxial cable calculation Sergio <invalid@invalid.com> - 2018-04-10 17:30 -0500
      Re: Coaxial cable calculation Lofty Goat <rlwatkins@gmail.com> - 2018-04-11 21:57 -0500
    Re: Coaxial cable calculation benj <benj@nobody.net> - 2018-04-10 15:54 -0400
      Re: Coaxial cable calculation Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au> - 2018-04-11 06:01 +1000

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