diff --git a/vortrag/bilder/radio.jpg b/vortrag/bilder/radio.jpg
new file mode 100644
index 0000000..c118a95
Binary files /dev/null and b/vortrag/bilder/radio.jpg differ
diff --git a/vortrag/hardware.tex b/vortrag/hardware.tex
index 6d1ab8e..161b498 100644
--- a/vortrag/hardware.tex
+++ b/vortrag/hardware.tex
@@ -125,5 +125,19 @@
     \end{column}
   \end{columns}
 \end{frame}
+\begin{frame}{Radio interface}
+  \begin{columns}
+    \begin{column}{6cm}
+        \begin{itemize}
+		\item At first a radio interface seemed to expensive.
+		\item Milosch told us a good dealer for the chips OpenBeacon uses.
+		\item The last protoype got a radio interface. It worked.
+	\end{itemize}
+    \end{column}
+    \begin{column}{6cm}
+        \includegraphics[height=4cm]{bilder/radio.jpg}
+    \end{column}
+  \end{columns}
+\end{frame}
 \end{document}