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Can someone help me build this LC resonant circuit? and explain it to me Answered

"An LCR circuit 1 is comprised of a capacitor 3, inductor 5, transformer T primary winding 9 and resistance 11 connected in series. It is assumed that the electrical conductors connecting the various circuit elements and forming the inductor 5 and primary winding 9 are perfect conductors; i.e., no DC resistance. Resistor 11 is a lump resistance equivalent to the total DC resistance of the actual circuit components and conductors. The inductor 5 is wound on a core 7"


A resonant circuit acts to amplify a selected frequency.

It works because the characteristics of a capacitor and inductor are almost the opposite.

When a capacitor discharges into the inductor 9a coil of wire round an iron core) a magnetic field is built up outside the inductor.

When the capacitor is discharged this field collapses and the falling field crossing the coils of wire creates an electric current to recharge the capacitor.

Once the field is collapsed the capacitor is charged and can discharge into the coil again.

Because the charge/discharge takes a set time depending on the value of the coil and capacitor the circuit "rings or resonates" at that frequency.

1/2 x pi x sqr root L x C = resonant frequency.

So you can see now that you need some more information before you can try to build the circuit.

See here for how to present that information.

Homework again?

Building it: Well, you aren't going to get perfect conductors unless you use cryogenic superconductors., but if you keep the wires short and are operating at lower frequencies that doesn't matter much. So: Get components (the diagram doesn't tell us what the values are for any of them; you'll have to either look that up in the document or calculate that depending on what you're trying to do with this circuit), wire them together, done.

It is not a homework assignment its a old patent I found in my attic ; I'll send the calculations, besides why the hell I'd post "Homework assignment" -.- thanks for all the response guys

Patent application by the look of the presentation of the drawing.


That was my thought. Could still be a homework assignment.

In any case, it's homework now -- to build it you need to first determine the values, and to determine the values you need to know what it's intended to do IN CONTEXT -- which means reading, analyzing, and actually understanding the patent disclosure.

Which is outside the scope of what I'd be willing to handle on Answers. If someone else wants to -- and if the querant is willing/able to provide enough information to do so -- go for it.

I think your right it smacks of a homework problem. Although I guess the actual question has been edited out. Still should be able solve it from the information given - It's likely to be all you get! That's education for you.