Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > sci.physics > #680570 > unrolled thread

Coaxial cable calculation

Back to article view | Back to sci.physics

Contents

  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

Page 1 of 2  [1] 2  Next page →

#680570 — Coaxial cable calculation

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.


-- 
Trevor Wilson
www.rageaudio.com.au

[toc] | [next] | [standalone]

#680582

On 4/10/2018 2:42 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.

You think that nobody is smart enough to even Google?

Answer is right in Wikipedia, you idiot.

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

But wait, this takes a little knowledge of mathematics so that lets you 
out. Slide rules were a stupid idea when it was a new idea. Hint: nobody 
even knows what they are anymore.

Just write L/C take square root set to 2000 and solve for inside 
diameter of outer conductor. Like I said you do need to know some algebra.

It's obvious you are not asking for the complex impedance since you 
didn't give enough information for that. Any idea what we are talking 
about here genius?

[toc] | [prev] | [next] | [standalone]

#680583

On 10/04/2018 7:20 PM, benj wrote:
> On 4/10/2018 2:42 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.
> 
> You think that nobody is smart enough to even Google?
> 
> Answer is right in Wikipedia, you idiot.
> 
> https://en.wikipedia.org/wiki/Coaxial_cable
> 
> But wait, this takes a little knowledge of mathematics so that lets you 
> out. Slide rules were a stupid idea when it was a new idea. Hint: nobody 
> even knows what they are anymore.

**I do. I still use a couple. Mostly for intellectual stimulation and a 
bit of fun. My scientific calculators make life too easy. The nice thing 
about slide rules is that you need to have a rough idea of the answer 
before you start.

> 
> Just write L/C take square root set to 2000 and solve for inside 
> diameter of outer conductor. Like I said you do need to know some algebra.
> 
> It's obvious you are not asking for the complex impedance since you 
> didn't give enough information for that. Any idea what we are talking 
> about here genius?

**I note your inability to supply a correct answer.

NEXT!


-- 
Trevor Wilson
www.rageaudio.com.au

[toc] | [prev] | [next] | [standalone]

#680642

On 4/10/2018 5:33 AM, Trevor Wilson wrote:
> On 10/04/2018 7:20 PM, benj wrote:
>> On 4/10/2018 2:42 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.
>>
>> You think that nobody is smart enough to even Google?
>>
>> Answer is right in Wikipedia, you idiot.
>>
>> https://en.wikipedia.org/wiki/Coaxial_cable
>>
>> But wait, this takes a little knowledge of mathematics so that lets 
>> you out. Slide rules were a stupid idea when it was a new idea. Hint: 
>> nobody even knows what they are anymore.
> 
> **I do. I still use a couple. Mostly for intellectual stimulation and a 
> bit of fun. My scientific calculators make life too easy. The nice thing 
> about slide rules is that you need to have a rough idea of the answer 
> before you start.
> 
>>
>> Just write L/C take square root set to 2000 and solve for inside 
>> diameter of outer conductor. Like I said you do need to know some 
>> algebra.
>>
>> It's obvious you are not asking for the complex impedance since you 
>> didn't give enough information for that. Any idea what we are talking 
>> about here genius?
> 
> **I note your inability to supply a correct answer.
> 
> NEXT!

The idea is the important thing, bunkie!
I note your usual fantasies of being the smartest person on the planet 
and everyone else being inferior to you.

[toc] | [prev] | [next] | [standalone]

#680742

On 4/10/2018 2:28 PM, benj wrote:
> On 4/10/2018 5:33 AM, Trevor Wilson wrote:
>> On 10/04/2018 7:20 PM, benj wrote:
>>> On 4/10/2018 2:42 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.
>>>
>>> You think that nobody is smart enough to even Google?
>>>
>>> Answer is right in Wikipedia, you idiot.
>>>
>>> https://en.wikipedia.org/wiki/Coaxial_cable
>>>
>>> But wait, this takes a little knowledge of mathematics so that lets
>>> you out. Slide rules were a stupid idea when it was a new idea. Hint:
>>> nobody even knows what they are anymore.
>>
>> **I do. I still use a couple. Mostly for intellectual stimulation and
>> a bit of fun. My scientific calculators make life too easy. The nice
>> thing about slide rules is that you need to have a rough idea of the
>> answer before you start.
>>
>>>
>>> Just write L/C take square root set to 2000 and solve for inside
>>> diameter of outer conductor. Like I said you do need to know some
>>> algebra.
>>>
>>> It's obvious you are not asking for the complex impedance since you
>>> didn't give enough information for that. Any idea what we are talking
>>> about here genius?
>>
>> **I note your inability to supply a correct answer.
>>
>> NEXT!
> 
> The idea is the important thing, bunkie!
> I note your usual fantasies of being the smartest person on the planet
> and everyone else being inferior to you.
> 

nothing wrong with that, Trump, Hillary, Putin, Mays, James McGinn, most
all the worlds leaders, Elizabeth Holmes, Martin Shkreli, Rahm Emanuel,
and especially Carlos Danger.

https://www.youtube.com/watch?v=vqJxp7w919o

Trevor asks for one equation, ez google, where one solves for D, but
typically we do not provide answers here for students homework, or
taking tests, and ask them to work through the problem so they can learn.

So, we are kicking this around for a while, to make sure it is past
homework/test time.

But you could go ahead and find the equation, rearrange terms to solve
for D, and post here.  then we can plug in #s.  [also include the cutoff
frequency equation]  Then we can show you where the solution is
impracticable. [like watts, materials, physical realization, delay...]

also realize that Zo is complex, and "characteristic impedance" is
typically limited to a range of frequency, some are broad, some are not,
so there is another term used when the cable is terminated with its
"characteristic impedance" then one measures VSWR and it needs to be
less than 1.2 for high power, and about 2 for other uses. This is also
calculated, and one needs to know frequency bands of intended use, as Zo
will spiral out of 2 VSWR to 20 and greater, or to 0.

[toc] | [prev] | [next] | [standalone]

#680781

On 4/11/2018 9:36 AM, Sergio wrote:
> On 4/10/2018 2:28 PM, benj wrote:
>> On 4/10/2018 5:33 AM, Trevor Wilson wrote:
>>> On 10/04/2018 7:20 PM, benj wrote:
>>>> On 4/10/2018 2:42 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.
>>>>
>>>> You think that nobody is smart enough to even Google?
>>>>
>>>> Answer is right in Wikipedia, you idiot.
>>>>
>>>> https://en.wikipedia.org/wiki/Coaxial_cable
>>>>
>>>> But wait, this takes a little knowledge of mathematics so that lets
>>>> you out. Slide rules were a stupid idea when it was a new idea. Hint:
>>>> nobody even knows what they are anymore.
>>>
>>> **I do. I still use a couple. Mostly for intellectual stimulation and
>>> a bit of fun. My scientific calculators make life too easy. The nice
>>> thing about slide rules is that you need to have a rough idea of the
>>> answer before you start.
>>>
>>>>
>>>> Just write L/C take square root set to 2000 and solve for inside
>>>> diameter of outer conductor. Like I said you do need to know some
>>>> algebra.
>>>>
>>>> It's obvious you are not asking for the complex impedance since you
>>>> didn't give enough information for that. Any idea what we are talking
>>>> about here genius?
>>>
>>> **I note your inability to supply a correct answer.
>>>
>>> NEXT!
>>
>> The idea is the important thing, bunkie!
>> I note your usual fantasies of being the smartest person on the planet
>> and everyone else being inferior to you.
>>
> 
> nothing wrong with that, Trump, Hillary, Putin, Mays, James McGinn, most
> all the worlds leaders, Elizabeth Holmes, Martin Shkreli, Rahm Emanuel,
> and especially Carlos Danger.
> 
> https://www.youtube.com/watch?v=vqJxp7w919o
> 
> Trevor asks for one equation, ez google, where one solves for D, but
> typically we do not provide answers here for students homework, or
> taking tests, and ask them to work through the problem so they can learn.
> 
> So, we are kicking this around for a while, to make sure it is past
> homework/test time.
> 
> But you could go ahead and find the equation, rearrange terms to solve
> for D, and post here.  then we can plug in #s.  [also include the cutoff
> frequency equation]  Then we can show you where the solution is
> impracticable. [like watts, materials, physical realization, delay...]
> 
> also realize that Zo is complex, and "characteristic impedance" is
> typically limited to a range of frequency, some are broad, some are not,
> so there is another term used when the cable is terminated with its
> "characteristic impedance" then one measures VSWR and it needs to be
> less than 1.2 for high power, and about 2 for other uses. This is also
> calculated, and one needs to know frequency bands of intended use, as Zo
> will spiral out of 2 VSWR to 20 and greater, or to 0.
> 
Yes, I could easily do all that. But Trevor thinks he's my boss and I 
should do everything he asks. Big Hint: He's not.

[toc] | [prev] | [next] | [standalone]

#680788

On 4/11/2018 1:38 PM, benj wrote:
> On 4/11/2018 9:36 AM, Sergio wrote:
>> On 4/10/2018 2:28 PM, benj wrote:
>>> On 4/10/2018 5:33 AM, Trevor Wilson wrote:
>>>> On 10/04/2018 7:20 PM, benj wrote:
>>>>> On 4/10/2018 2:42 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.
>>>>>
>>>>> You think that nobody is smart enough to even Google?
>>>>>
>>>>> Answer is right in Wikipedia, you idiot.
>>>>>
>>>>> https://en.wikipedia.org/wiki/Coaxial_cable
>>>>>
>>>>> But wait, this takes a little knowledge of mathematics so that lets
>>>>> you out. Slide rules were a stupid idea when it was a new idea. Hint:
>>>>> nobody even knows what they are anymore.
>>>>
>>>> **I do. I still use a couple. Mostly for intellectual stimulation and
>>>> a bit of fun. My scientific calculators make life too easy. The nice
>>>> thing about slide rules is that you need to have a rough idea of the
>>>> answer before you start.
>>>>
>>>>>
>>>>> Just write L/C take square root set to 2000 and solve for inside
>>>>> diameter of outer conductor. Like I said you do need to know some
>>>>> algebra.
>>>>>
>>>>> It's obvious you are not asking for the complex impedance since you
>>>>> didn't give enough information for that. Any idea what we are talking
>>>>> about here genius?
>>>>
>>>> **I note your inability to supply a correct answer.
>>>>
>>>> NEXT!
>>>
>>> The idea is the important thing, bunkie!
>>> I note your usual fantasies of being the smartest person on the planet
>>> and everyone else being inferior to you.
>>>
>>
>> nothing wrong with that, Trump, Hillary, Putin, Mays, James McGinn, most
>> all the worlds leaders, Elizabeth Holmes, Martin Shkreli, Rahm Emanuel,
>> and especially Carlos Danger.
>>
>> https://www.youtube.com/watch?v=vqJxp7w919o
>>
>> Trevor asks for one equation, ez google, where one solves for D, but
>> typically we do not provide answers here for students homework, or
>> taking tests, and ask them to work through the problem so they can learn.
>>
>> So, we are kicking this around for a while, to make sure it is past
>> homework/test time.
>>
>> But you could go ahead and find the equation, rearrange terms to solve
>> for D, and post here.  then we can plug in #s.  [also include the cutoff
>> frequency equation]  Then we can show you where the solution is
>> impracticable. [like watts, materials, physical realization, delay...]
>>
>> also realize that Zo is complex, and "characteristic impedance" is
>> typically limited to a range of frequency, some are broad, some are not,
>> so there is another term used when the cable is terminated with its
>> "characteristic impedance" then one measures VSWR and it needs to be
>> less than 1.2 for high power, and about 2 for other uses. This is also
>> calculated, and one needs to know frequency bands of intended use, as Zo
>> will spiral out of 2 VSWR to 20 and greater, or to 0.
>>
> Yes, I could easily do all that. But Trevor thinks he's my boss and I
> should do everything he asks. Big Hint: He's not.

I worked for a while for a guy a bit like Trump, he used to say, "its my
way or the highway" in his staff meetings,  His name was Clive, part
russian, you could not reason with him, he would tell you what is, and
you could suggest things. He liked to rule by fear (old school stuff),
so I avoided him where I could.

But... Clive was like a loose cannon, and we used Clive too,  just
suggest a reason, he would get a name,  and then he would go and blast
somebody.  (perhaps Trump is getting aimed by Tweeter?)

anyhow he drove off a lot of good people, then he got the axe.  One Guy,
Bob, when Clive for the first time said "its my way or the highway", Bob
said "Ok, By By!", walked out of the meeting and quit that day and got a
better $$$ job a week later, without the BS.

anyhow Trump is far better than Hillary.
Paul Ryan is saying he is not going to run again.

[toc] | [prev] | [next] | [standalone]

#680645

On 4/10/2018 5:33 AM, Trevor Wilson wrote:
> On 10/04/2018 7:20 PM, benj wrote:
>> On 4/10/2018 2:42 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.
>>
>> You think that nobody is smart enough to even Google?
>>
>> Answer is right in Wikipedia, you idiot.
>>
>> https://en.wikipedia.org/wiki/Coaxial_cable
>>
>> But wait, this takes a little knowledge of mathematics so that lets 
>> you out. Slide rules were a stupid idea when it was a new idea. Hint: 
>> nobody even knows what they are anymore.
> 
> **I do. I still use a couple. Mostly for intellectual stimulation and a 
> bit of fun. My scientific calculators make life too easy. The nice thing 
> about slide rules is that you need to have a rough idea of the answer 
> before you start.

When I was a student, we were cleaning out an old storeroom at school 
and came across this large nifty wooden box. When we opened it up there 
was this large cylinder with a bunch of sticks with scales on them 
fastened to it. The teacher explained it was like a 6 foot slide rule! 
Obviously it was super accurate, but the hard part was you had to figure 
out which scale on the cylinder was the one to read for the answer. Talk 
about need to know the answer before you get the answer!

[toc] | [prev] | [next] | [standalone]

#680585

benj <benj@nobody.net> Wrote in message:
> On 4/10/2018 2:42 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.
> 
> You think that nobody is smart enough to even Google?
> 
> Answer is right in Wikipedia, you idiot.
> 
> https://en.wikipedia.org/wiki/Coaxial_cable
> 
> But wait, this takes a little knowledge of mathematics so that lets you 
> out. Slide rules were a stupid idea when it was a new idea. Hint: nobody 
> even knows what they are anymore.
> 
> Just write L/C take square root set to 2000 and solve for inside 
> diameter of outer conductor. Like I said you do need to know some algebra.
> 
> It's obvious you are not asking for the complex impedance since you 
> didn't give enough information for that. Any idea what we are talking 
> about here genius?

Internet creates "brave" people
who would hasitate to say the same face to face.


-- 
Libor Striz aka Poutnik ( a pilgrim/wanderer/wayfarer)


----Android NewsGroup Reader----
http://usenet.sinaapp.com/

[toc] | [prev] | [next] | [standalone]

#680644

On 4/10/2018 6:24 AM, Libor Striz wrote:
> benj <benj@nobody.net> Wrote in message:
>> On 4/10/2018 2:42 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.
>>
>> You think that nobody is smart enough to even Google?
>>
>> Answer is right in Wikipedia, you idiot.
>>
>> https://en.wikipedia.org/wiki/Coaxial_cable
>>
>> But wait, this takes a little knowledge of mathematics so that lets you
>> out. Slide rules were a stupid idea when it was a new idea. Hint: nobody
>> even knows what they are anymore.
>>
>> Just write L/C take square root set to 2000 and solve for inside
>> diameter of outer conductor. Like I said you do need to know some algebra.
>>
>> It's obvious you are not asking for the complex impedance since you
>> didn't give enough information for that. Any idea what we are talking
>> about here genius?
> 
> Internet creates "brave" people
> who would hasitate to say the same face to face.

"hasitate"??!! Watch out Trevor LIVES to find typos and then use that as 
"proof" that a person is stupid.

Anyway, you political noob, Trevor and I are pros, What we say is just 
business. Face to face, we'd go out to lunch and have a couple of drinks 
together like any professionals would. I can't believe how many people 
actually think that what they see on the INTERNET or on TV is real. <sigh>

Got the answer to that problem yet? I'm too dumb to know how to multiply 
the numbers to get an answer.  (Anyway, multiplying numbers is a job for 
machines, not people)

[toc] | [prev] | [next] | [standalone]

#680616

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 ?

[toc] | [prev] | [next] | [standalone]

#680618

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...

-- 
Libor Striz aka Poutnik ( a pilgrim/wanderer/wayfarer)


----Android NewsGroup Reader----
http://usenet.sinaapp.com/

[toc] | [prev] | [next] | [standalone]

#680620

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.

-- 
Goat

[toc] | [prev] | [next] | [standalone]

#680624

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)

[toc] | [prev] | [next] | [standalone]

#680651

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!

[toc] | [prev] | [next] | [standalone]

#680676

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 ?

Extra Credit Question: anyone know what the term "lizard" means on
campus ? (think way-way back)

[toc] | [prev] | [next] | [standalone]

#680678

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.



-- 
Trevor Wilson
www.rageaudio.com.au

[toc] | [prev] | [next] | [standalone]

#680682

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

[toc] | [prev] | [next] | [standalone]

#680683

On 11/04/2018 8:38 AM, Sergio wrote:
> 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.

**Did all I needed. All the scientific functions, four levels of 
parentheses and a power-gobbling red LED display.



-- 
Trevor Wilson
www.rageaudio.com.au

[toc] | [prev] | [next] | [standalone]

#680738

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...

[toc] | [prev] | [next] | [standalone]

Page 1 of 2  [1] 2  Next page →

Back to top | Article view | sci.physics

csiph-web