hi scott, the 159 is a constant, just like pi. its just part of the
formula. but it is always 159. i have seen other formulas that do
the same thing but some are very confusing and are way to hard to
work with. c u 73 mike w6quv
At 02:59 AM 1/17/2012, you 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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