I won't beat this to death.  I promise!

I looked at Mike's version of the formula, and I understand the rationale.
For RF circuits, the component values are usually stated in microhenries and
picoFarads (or micro-microfarads in the olden days).  

So the resonant frequency of a 1 pF capacitor and a 1 uH coil (the micro
symbol is the Greek letter mu, so people sometimes write u for it) is 1 over
the quantity 2 times pi times the square root of ten to the minus 6 times
ten to the minus 12, end square root, end fraction.  1 over 2 pi is about
.159.  Ten to the minus 6 times ten to the minus 12 is ten to the minus 18.
The square root of ten to the minus 18 is ten to the minus 9.  The
reciprocal of ten to the minus 9 is ten to the 9 or one billion.  So the
resonant frequency is 1 gigaHertz times .159, or 159 megaHertz.  So raising
the capacitance, the inductance or both will lower the frequency.  

We get into a whole nuther discussion when we make the inductor and
capacitor non-ideal, meaning that they have some resistance, so that the
resonant circuit doesn't have an infinite Q factor nor an infinitely narrow
bandwidth.  There are formulas for these things, also.

I hope this helps somebody.  If not, I'll QRT.
73,
Lloyd Rasmussen, W3IUU, Wheaton, Maryland
Home:  http://lras.home.sprynet.com
Work:  http://www.loc.gov/nls
 
> -----Original Message-----
> From: For blind ham radio operators [mailto:[log in to unmask]]
> On Behalf Of Scott Howell
> Sent: Tuesday, January 17, 2012 6:00 AM
> To: [log in to unmask]
> Subject: Re: requesting help with math question
> 
> 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...