\documentclass[border=10pt,pstricks]{standalone}
\usepackage{pst-node,amsmath}
\begin{document}
\begin{pspicture}[showgrid](-5,-5)(5,5)
\newcommand{\hinhtron}[4]{
\pscircle(0,0){1}
\psline(1;45)(1;-135)
\psline(1;-45)(1;135)
\rput(.5,0){#1}
\rput(0,.5){#2}
\rput(-.5,0){#3}
\rput(0,-.5){#4}
}
\psnode(-2,0){A}{\hinhtron{0}{1}{0}{}}
\ncline[nodesep=1cm]{->}{A}{B}
\naput{9} \nbput{$x_1$}
\pnodes(-2,0){L}
\pnode([nodesep=1,angle=15]A){Q}
\psdot(Q)
\end{pspicture}
\end{document}
If the letter A is replaced by L, so:
\pnode
is empty, a\psnode
has a contents.pnodes
is also available.