cyb0rg777
New Member
I was figuring up some resonant circuits.
I haven't had time to learn latex very well so I'll try to do the best I can.
So I started with this resonant formula.
[latex]F=\frac{1}{2\pi sqrt {LC}}[/latex]
I found the value for L with a 20pf capacitor at 440mhz by changing it to this formula.
[latex]L=\frac{\frac{\frac{1}{F}}{2\pi}^2}{C}[/latex]
Now I'm looking for how many turns of an air core inductor I need to make a 6.5419nH coil with a diameter of 3.175mm(.125") and 12.7mm(.5") length.
I'm starting with this formula.
[latex]L=\frac{.001 N^2 r^2}{228r+254l}[/latex]
L= inductance in henries
r=radius in meters
l=length in meters
N= number of turns
So I rearranged it to this to get the number of turns.
[latex]N=sqrt(\frac{L(228r+254l)}{.001r^2})[/latex]
But when I check my answer it comes out wrong.
Could you help me out ?
My math is not very good.
I haven't had time to learn latex very well so I'll try to do the best I can.
So I started with this resonant formula.
[latex]F=\frac{1}{2\pi sqrt {LC}}[/latex]
I found the value for L with a 20pf capacitor at 440mhz by changing it to this formula.
[latex]L=\frac{\frac{\frac{1}{F}}{2\pi}^2}{C}[/latex]
Now I'm looking for how many turns of an air core inductor I need to make a 6.5419nH coil with a diameter of 3.175mm(.125") and 12.7mm(.5") length.
I'm starting with this formula.
[latex]L=\frac{.001 N^2 r^2}{228r+254l}[/latex]
L= inductance in henries
r=radius in meters
l=length in meters
N= number of turns
So I rearranged it to this to get the number of turns.
[latex]N=sqrt(\frac{L(228r+254l)}{.001r^2})[/latex]
But when I check my answer it comes out wrong.
Could you help me out ?
My math is not very good.
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