\documentclass[11pt,a4paper]{article}
\usepackage{graphics,pstricks,sfg}
\pagestyle{empty}
\setlength{\parindent}{0pt}

\begin{document}
\sfgsetunit{0.5cm}
\sfgsetsize{0.12}{0.4}{0.5}{0.3}
\sfgsetcompass
\begin{picture}(27,4)
                                % branches related to node 2
  \put(6,2){\sfgbranch{3}{0}\S{$\frac{1}{R_1}$}}
  \put(9,2){\sfgbranch{3}{0}\N{\boldmath $Z_2$}}
  \put(18,2){\sfgcurve{-9}{0}{2}\S{$\frac{1}{R_2}$}}
  \put(24,2){\sfgcurve{-15}{0}{-2}\N{$sC_1$}}
                                % branches related to node 3
  \put(12,2){\sfgbranch{3}{0}\N{$\frac{1}{R_2}$}}
  \put(15,2){\sfgbranch{3}{0}\N{\boldmath $Z_3$}}
                                % input, voltage gain, output
  \put(0,2){\sfgcurve{6}{0}{2}\N{$1$}}
  \put(18,2){\sfgcurve{6}{0}{-2}\S{$\alpha_{\mathrm{V}}$}}
  \put(24,2){\sfgbranch{3}{0}\S{$1$}}
                                % nodes
  \put(0,2){\sfgtermnode\S{$V_{\mathrm{in}}$}}
  \put(3,2){\sfgnode\S{$I_1$}}
  \put(6,2){\sfgnode\S{$V_1$}}
  \put(9,2){\sfgnode\S{$I_2$}}
  \put(12,2){\sfgnode\S{$V_2$}}
  \put(15,2){\sfgnode\S{$I_3$}}
  \put(18,2){\sfgnode\S{$V_3$}}
  \put(21,2){\sfgnode\S{$I_4$}}
  \put(24,2){\sfgnode\S{$V_4$}}
  \put(27,2){\sfgtermnode\S{$V_{\mathrm{out}}$}}
\end{picture}
\end{document}
