In older linacs the cable between the PFN and the diode stack gives
every now and then a short circuit.
I have tried to make replacements without much success. In newer
machines a gray cable is used (I think from diagnostic equipment).
This new cable never fails so order this new type at Elekta.
![\begin{figure}{\includegraphics[height=0.6\textheight]{/local_scratch/kok/faq/plaatjes/htcable.eps}}
\end{figure}](img68.png)