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Subject:
From:
colin McDonald <[log in to unmask]>
Reply To:
colin McDonald <[log in to unmask]>
Date:
Tue, 17 Jan 2012 16:35:52 -0700
Content-Type:
text/plain
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text/plain (114 lines)
are these circuits always in peako ferrads and micro henries?  if so, then 
using 159 just moves the decimal point to solve with those values instead of 
having to work out the ferrads and henries first.

73
Colin, V A6BS
----- Original Message ----- 
From: "Butch Bussen" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Tuesday, January 17, 2012 7:19 AM
Subject: Re: requesting help with math question


> It is 1 over 2 pi which is the original formula.  1 over 6.28 is .159
> 73
> Butch
> WA0VJR
> Node 3148
> Wallace, ks.
>
>
> On
> Tue, 17 Jan 2012, Scott Howell wrote:
>
>> Mike,
>>
>> I see how this works, but one question is where does the 159 come from? =
>> Just curious and hey if it works that is fine by me. Any other tips? =
>> grin
>> Like I said, math is my weakness and something I have always wanted to =
>> understand. I used to be afraid of math which seems pretty silly, but I =
>> really find the subject fascinating now and wish I had the same attitude 
>> =
>> when I was younger. I'm not really sure where I went wrong in my study =
>> of math and why I never learn to appreciate the value of subjects like =
>> algebra. Probably just did not have the right teachers when I was young =
>> and impressionable. grin
>>
>> 73
>> Scott/N3BYY
>> On Jan 17, 2012, at 12:20 AM, Mike Cozzolino wrote:
>>
>>> hello scott, i tried to follow your formula, but the way you wrote 
>>> it=20=
>>
>>> i couldn't follow it.  anyway scott, why don't you use the formula 
>>>  >>=20=
>>
>>> f=3D159 over the square root of l times c <<.  first you multiply the =
>> l=20
>>> times c and then you get the square root of that answer.  then you=20
>>> take the 159 and devide that by your answer.  the answer i got using=20=
>>
>>> the values you gave, 50 microhenries and 200 pico farads was 1.59. 
>>> i=20=
>>
>>> left the values at their original values picos and=20
>>> microhenries.  thats the formula i always use for resonance of a=20
>>> tuned circuit.  73 bl c u mike w6quv
>>> =20
>>> =20
>>> =20
>>> At 07:06 AM 1/16/2012, you wrote:
>>>> All,
>>>> =20
>>>> Ok, I'm studying away here and trying to master the material for the =
>> =3D
>>>> Extra class exam. I have to admit that my math skills are not the =
>> best, =3D
>>>> but in my defense I have not done such fun stuff when in school and 
>>>> =3D=
>>
>>>> certainly never took much algebra. So, I'm admitting my mathematical  =
>> =3D
>>>> ignorance  here and asking for a little mercy. grin
>>>> I want to understand how best to work out these problems because =3D
>>>> remembering the answers is probably almost as much work. grin
>>>> So, here is the question and this is dealing with resonance.
>>>> The forumla f sub r =3D3D r squared times l squared.
>>>> So, f is the resonant frequency and I got that and that is what I =
>> need =3D
>>>> to solve for.
>>>> So, r is 50 micro henrys and l is 200 pico farads.
>>>> I understand that I need to convert micro henrys to henrys and pico 
>>>> =3D=
>>
>>>> farads to farads. I gather multiplying 50 times 10 to minus 6 gets =
>> the =3D
>>>> job done and doing this on a calculator would be 50 times 10 (press =
>> the =3D
>>>> x y button) -6.
>>>> You would do the same for converting pico farads to farads.
>>>> However, at this point I'm not quite sure how to work out the rest =
>> and =3D
>>>> of course entering this into a scientific calculator is really =
>> important =3D
>>>> and would make the process a bit easier.
>>>> I realize the end result will be an answer that is in megahertz. If 
>>>> =3D=
>>
>>>> anyone could help with this I would really appreciate it. The =
>> electrical =3D
>>>> theory portion of the exam is going to be the difficult part for me. =
>> =3D
>>>> RUles etc. no problem, but this stuff which I'm sure is going to be a =
>> =3D
>>>> big part of the exam is going to be the make or break for me.
>>>> =20
>>>> thanks,
>>>> 73
>>>> Scott/N3BYY=3D
>>
>> 

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