抄録
In order to determine the sub-standard ionization gauges, many factors influencing the sensitivity of the gauges were investigated in detail.
For the calibration of the sub-standard gauges with the standard McLeod gauge, it is required that the deviations of the sensitivity is within one per cent in the pressure range of 10-4 to about 10-3 mm. of mercury.
Experiments have been carried out under many conditions.i. e. changing the values of pressure, sorts of gases, electron currents and potentials of electrodes, for several types and dimensions of gauges. In these experiments, we obtained an optimum condition for a gauge having sensitivity constancy for pressures up to 3×10-3 mm of mercury while we found such an unfavourable phenomena that the stability tended to decrease slowly during five to twenty-five hours after the outgassing procedure of electron bombardment.
