% Author: Prof. Dr. Matthias Jung, DL9MJ
% Year: 2024
\begin{tikzpicture}
    \draw[Triangle-Triangle] (0.1,2.4) -- (2*pi,2.4);
    \draw (pi,2.4) node[above]{$T$};
    \draw[-Triangle] (0,0) -- (2.1*pi,0) node[below]{$t$};
    \draw[-Triangle] (0,2*-1.1) -- (0,2*1.3) node[above]{$U$};
    \foreach \x in {1,...,6}{
        \draw (\x,-.1) -- (\x,.1);
    }
    \draw[Triangle-Triangle] (.5*pi,0) -- (.5*pi,2);
    \draw (.5*pi,1) node[right,text width=pi]{$\hat{U}$}; 
    \draw[Triangle-Triangle] (1.5*pi,-2) -- (1.5*pi,2);
    \draw[DARCgray] (.5*pi+0.1,2) -- (1.5*pi-0.1,2);
    \draw (1.5*pi,1) node[right]{$U_\text{ss}$};
    \draw[color=DARCred,very thick] plot[domain=0:2*pi,smooth] (\x,{2*sin(\x r)});
    \draw[Triangle-Triangle] (pi,0) -- (pi,1.4);
    \draw[DARCgray](.75*pi,1.4) -- (pi,1.4);
    \draw (pi,0.7) node[right,text width=pi]{$U_\text{eff}$};
\end{tikzpicture}