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Re: Coaxial cable calculation

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On 4/11/2018 6:36 AM, benj wrote:
> On 4/10/2018 6:24 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.
> 
> As for me, when he HP35 came out, I knew my life was saved. So in spite
> of the VERY high cost I just sucked it up and plunked em down. Don't
> about OZ but here there were these Ads all over TV for the "Bomar brain"
> which was like the first cheap 4 banger. They must have sold a lot until
> TI came out with their cheaper version of the HP.
> 
> For many years after slide rules disappeared I had a little plastic
> circular one that fit in my shirt pocket. I'd take to the grocery store
> and you could set price on one scale and package weight on the other and
> get a ratio going and that way I could easily determine the best buy
> even though all the packages were odd weights and different from each
> other.
> 
> But analog computing has no future...

there are a fewanaloge computers on Ebay, very pricy, and do little,
remember all those opamps, and dials ? could do earth moon orbits on it.

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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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