how to fix ...
 
 
Here are some pictures taken during the Clinac double repair in March 2007. See the captions for details. Thanks to Bruno, Gerhard and Werner from Varian Medical Systems for doing a good job!
... two clinacs at the same time
The bad pulse cable from Linac Blue.
The Modulator end. High voltage design.
Under the floor, the cable runs to the Stand.
At the stand, the cable comes up again.
The Modulator’s pulse forming network.
Gerhard and Bruno trying to get the cable from Linac Green.
When taking this photo, my camera said: “Face detected!”
The attempt was stopped when the ordered cable arrived.
Romeo with the new cable.
It was a little longer than expected.
Werner sorting things out.
Hey! I found the end!
The cable seems to be long enough to connect to Linac Green.
Looks like in the U.S., ...
... Modulator and Gantry are in different buildings.
Niko supervises the scene.
RT Vice president Andy gives a helping hand.
The cable is stuffed under the floor.
Private Günther, fully concentrated. Waiting for orders.
The bad cable. Note the hole ...
... where the spark came through. In humans, we call this a “stroke”.
Meanwhile, on Linac Green.
While waiting for the new ion chamber, ...
... the opportunity is taken to replace the dying lasers.
They now have remote control. Works also for TV. And in the disco.
Finally, the chamber arrives in the pressure safe. Pffft!!
The old ion chamber. The transverse module had developed ..
... a dependence on dose rate. This cannot be adjusted.
Therefore, the original chamber from 1996 has to be replaced.
The patient side.
The target side.
Friday: Clinac Green recovering after brain surgery.
Now the beams have to be calibrated.
This is done with the water phantom, the LA48 and the 2D-Array.
Control room of Linac Green. Linac Blue (in the back) is clinical again.
The laptop shows the measured beam profiles.
First, the beam is set up with open beam steering loops.
The PTW system gives realtime information.
Then the servos are calibrated and locked.
Only if symmetry is better than 1.0% for all energies, we are satisfied.
BeamAdjust from the MCC software saved a lot of time.
Now Physics takes over for absolute dosimetry.