How to draw an inductive coupling with circuitikz and TikZ?

Question

I'd want to draw a circuit with an inductive coupling, as you can see in the following image:

What I need now is putting the dots related to the inductive coupling, as well as the power lines. I think I could draw these last ones using TikZ if they were flat, but as they are wavy, I don't know how to do it.

This is the code I've written till now (I've put two lines between both coupled inductors):

\documentclass[border=2pt]{standalone}
\usepackage{circuitikz}

 \begin{document}
\begin{figure}
\centering
\begin{circuitikz}
  \draw (0,0) to [short,o-o] (8,0);
  \draw (0,1.5) to [short,o-] (3,1.5);
  \draw (5,1.5) to [short,-o] (8,1.5);
  \draw (3,1.5) to [inductor] (5,1.5);
  \draw (6,2.5) to [short] (5,2.5) to [inductor] (3,2.5) to [short] (2,2.5) to [short] (2,3.5) to [C] (6,3.5) to [short] (6,2.5);
  \draw (2,3.5) to [short] (2,4.5) to [inductor] (6,4.5) to [short] (6,3.5);
  \draw (2,4.5) to [short] (2,5.5) to [resistor] (6,5.5) to [short] (6,4.5);
  \draw[-] (3.5,1.95) -- (4.5,1.95) node{};
  \draw[-] (3.5,2.05) -- (4.5,2.05) node{};
\end{circuitikz} 
\end{figure}
\end{document}

How could I complete this drawing?

Thank you.

Answer 1

To draw the "wavy" lines, you can use the snake line pattern offered by the decorations.pathmorphing library. Play with the segment length and amplitude parameters to get the exact line style you want.

Code

\documentclass[border=2pt]{standalone}
\usepackage{circuitikz}
\usetikzlibrary{tikzmark,decorations.pathmorphing}

\begin{document}
\begin{circuitikz}
  \draw (0,0) to [short,o-o] (8,0);
  \draw (0,1.5) to [short,o-] (3,1.5);
  \draw (5,1.5) to [short,-o] (8,1.5);
  \draw (3,1.5) to [inductor] (5,1.5);
  \draw (6,2.5) to [short] (5,2.5) to [inductor] (3,2.5) to [short] (2,2.5) to [short] (2,3.5) to [C] (6,3.5) to [short] (6,2.5);
  \draw (2,3.5) to [short] (2,4.5) to [inductor] (6,4.5) to [short] (6,3.5);
  \draw (2,4.5) to [short] (2,5.5) to [resistor] (6,5.5) to [short] (6,4.5);
  \draw[-] (3.5,1.95) -- (4.5,1.95) node{};
  \draw[-] (3.5,2.05) -- (4.5,2.05) node{};

  % wavy lines
  \draw[->,decorate,decoration={snake,segment length=30pt,amplitude=4pt}](0,.75)--(2,.75);
  \draw[->,decorate,decoration={snake,segment length=30pt,amplitude=4pt}](6,.75)--(8,.75);
\end{circuitikz} 
\end{document}

Output

Answer 2

You can also use PSTricks:

\documentclass{article}

\usepackage{pst-circ,pst-plot}
\newcommand*\CurvedArrow[4]{
  \rput(#1,0){
    \psplot[algebraic]{0}{#2}{#3*sin(6*x)+#4}
    \psline{->}(#2,#4)(!#2 0.15 add #4)
  }
}

\begin{document}

\begin{pspicture}(-0.4,-0.1)(7.3,8.8)
  \wire[arrows=*-*](0,0)(7,0)
  \coil[arrows=*-*](0,2)(7,2){}
  \coil(6,3.5)(1,3.5){}
  \psline(2.5,2.75)(4.5,2.75)
  \capacitor[arrows=*-*](1,5)(6,5){$C$}
  \coil[arrows=*-*](1,6.5)(6,6.5){$L$}
  \resistor[dipolestyle=zigzag](1,8)(6,8){$R$}
  \wire(1,3.5)(1,8)
  \wire(6,3.5)(6,8)
  \psdots[dotsize=2pt](5.5,2.15)(5.5,3.65)
  \rput(6.2,2.15){$n$}
  \rput(6.2,3.65){$l$}
  \CurvedArrow{-0.4}{1.05}{0.2}{1}
  \CurvedArrow{6.1}{1.05}{0.2}{1}
\end{pspicture}

\end{document}

It can almost certainly be made simpler but here is my first try.

Answer 3

For the coupling of the inductors, I'd go like this:

\documentclass{article}
\usepackage{circuitikz}
\begin{document}
\begin{circuitikz} \draw
    (0,0) node[transformer] (T) {}
    (T.A1) node[above] {A1}
    (T.B2) node[anchor=west] {B2}
    (T.A1) node[below right=2mm] {$\bullet$}
    (T.B2) node[above left=2mm] {$\bullet$}
    (T.A1) -| (-1.5,1) to[C] (-3,1) |- (T.A2)
;\end{circuitikz}
\end{document}