Berthold LB 134, User Manual

Page: 103 / 157

LB 134 7. Probes for the LB 134
93
Figure 7.9: Assembly of counter tube window
7.3.2 LB 1231 with Beta-Gamma Counter Tube
LB 6357
This counter tube is filled with Xenon and tightly sealed. Neither
refilling nor flushing is required; therefore, this counter tube
does not include any refill nozzles or valves. The Xenon counter
tube for the measurement of beta and gamma radiation cannot
be opened by the user. The window foil (5 mg/cm² Titan foil)
can only be replaced by Berthold. However, the mesh grid
frame can be removed to clean the foil.
The beta-gamma counter tube may also be inserted into a wall
bracket for semi-stationary operation.
7.3.3 Counter Tube Change
The counter tube attached to the hand probe case by snap
locks can easily be changed without any tools.
A counter tube must be replaced if you want to switch from be-
ta-gamma to alpha-beta measurements and vice versa. The
sealed Xenon-filled counter tube LB 6357 is used for beta-
gamma measurements. The P-10 flow-through counter tube LB
6359 is used for alpha-beta measurements. A counter tube
change is also required when a defective counter tube must be
replaced by a new one.
When replacing counter tubes, please make sure that

the LB134 is off

the foam rubber edge is not damaged

the replacement takes place in a dry and clean envi-
ronment

and that under no circumstances moisture or dirt can
penetrate into the
gap!
Proceed as follows to replace the counter tube