InstroTek
44
The Probe Electronic Assembly consists of the connector, brass
plug housing a ferrite transformer, an amplifier PC-Assembly,
and an HVPS PC-Assembly. Both of these are mounted on a
tray and the detector tube itself. These items are shown in
Figure 7.2.
Field repair of the probe electronic assembly will generally be
limited to a physical examination for loose items. The connector
pins at each end of the PC-Assemblies should be engaged and
the brass rings on each end of the tray should be tight.
If moisture is observed inside the probe and no permanent
damage has occurred it can be dried by placing in a
household oven for one hour on warm (140º to 158º F, 60º to 70º
C).
The radioactive source is mounted in the base of the Source
Tube Assembly. Do not grasp the base with your hand. The
Source Tube Assembly should be placed back in the Surface
Mechanical Assembly during repair of the Probe Electronic
Assembly.
Probe Re-Installation
When re-installing the repaired or exchanged Probe Electronic
Assembly in the Source Tube Assembly, insure that the threads
are properly engaged and make sure the probe electronics
threads are no longer visible to ensure a good seal. Thread
together the assemblies almost all the way by hand and then
apply a thin coating of silicon grease to the O-ring. Use the
spanner wrench to compress the O-ring to insure a moisture
seal.
WARNING
