Varian 563-P Ion Gauge

unique with its high-pressure capability and low x-ray limit, the 563 tube is usable to
1x10-1 torr in argon and 6x10-2 torr in air. this is accomplished by the smaller geometry of
the tube elements and the use of a conductive platinum coating on the inside of the glass
envelope which improves gauge tube performance.
in high and ultra-high vacuum ranges, a platinum shield prevents external electrical fields
from affecting the low ion current. in higher pressure ranges where the number of ions
produced is much greater, the platinum conductive coating drains off the static charge
which can build up on the inside of the glass tube. thus, the 563 tube gives superior
performance throughout the entire range of the tube.