% Author: Prof. Dr. Matthias Jung, DL9MJ
% Year: 2024
% (3)
\begin{tikzpicture}
    \ctikzset{
        inductors/scale=2.5,
        capacitors/scale=2.5
    }

    % Schwingkreis
    \draw (0,0) coordinate(h0)
        to [cute inductor, inductors/coils=5, name={l}] ++(0,-2)
        to [short] ++(2,0) coordinate(h1)
        to [C, name={c}] ++(0,2)
        to [short, i={I}] (h0);

    % Margin:
    \useasboundingbox[red] (-0.5,+0.25) rectangle (+2.5,-2.25);

    % Feldlinien Kapazität:
    \Distance{(c.north east)}{(c.south east)}{\d}
    \foreach \i in {0,2,4,6}{
        \draw[DARCorange, -Triangle]
            (c.north east) ++(\i*\d/\getDarcImageFactor/6, 0) coordinate(start\i)
            -- (start\i|-c.north west) coordinate(end\i);
        \draw[DARCred]  (start\i) node[anchor=south](){$+$};
        \draw[DARCblue] (end\i)   node[anchor=north](){$-$};
    }
    \draw(c.north east) to [open, name={x1}] (c.north west);
    \draw[DARCorange](x1.center) node[anchor=east](){E};

    % Feldlinien Induktivität:
    \Distance{(l.south west)}{(l.north west)}{\e}
    \foreach \i in {2,3}{
        % Geraden:
        \draw[DARCgreen]
            (l.south west) ++(\i*\e/\getDarcImageFactor/5, 0) coordinate(start\i)
            -- (start\i|-l.south east) coordinate(end\i);
        
        \ifthenelse{\i<3}
        {
            \tikzmath{
                \j = \i + 0;
                \dir = -1.0;
                \h = \i*\e/5;
                \w = \dir*\e/5*\j;
            }
        }{
            \tikzmath{
                \j = \i - 2;
                \dir = +1.0;
                \h = (3-(\i-2))*\e/5;
                \w = \dir*\e/5*(5-\i);
            }
        }

        % Oben:
        \draw(start\i) ++( 0,+\h) coordinate(c1);
        \draw(start\i) ++(\w,+\h) coordinate(c2);
        \draw[DARCgreen] (start\i) .. controls (c1) and (c2) .. (c2|-l.north);
        % Unten:
        \draw(end\i) ++( 0,-\h) coordinate(c1);
        \draw(end\i) ++(\w,-\h) coordinate(c2);
        \draw[DARCgreen] (end\i) .. controls (c1) and (c2) .. (c2|-l.north);

        \draw[DARCgreen, fill=DARCgreen](c2|-l.north) node [draw=DARCgreen, fill=DARCgreen, inputarrow, rotate=+90] () {};

        \ifthenelse{\i=3}{
            \draw[DARCgreen](c2|-l.north) node [anchor=west] () {H};
        }{}
    }

\end{tikzpicture}%