These dual tungsten glass ion gauge tubes have a ISO KF-25 vacuum connection flange and an operating range from 1x10-3 to 2x10-10 Torr. These ion gauge tubes are compatible with most modern hot cathode ion gauge tubes. They have a sensitivity of 10 Torr-1 and standard operating voltages (collector 0 VDC, Grid +180 VDC, filament -30 VDC with 5 VAC).
The hot tungsten filaments react with oxygen to rapidly form tungsten oxide and therefore poor vacuum can rapidly cause catastrophic oxidation of hot tungsten components. They are most practical in environments having little risk of oxygen exposure. However, tungsten filamets are suited for applications where backstreaming of oil from diffusion pumps is heavy.
Dual tungsten filament ion gauge tubes can be identified by two opposing helical filaments and have six external leads at the plug end. Our replacement ion gauge tubes work with most hot cathode ion gauge controllers made by Granville Phillips, MKS Instruments, Perkin Elmer, Varian, & Veeco.