A Recording Microwave Spectrograph

The principle of operation and the fundamentals of realization of a recording microwave spectrograph designed for use in the study of the absorption and the index of refraction of gases under medium pressures (1 mm Hg to 1 atm) are presented. The apparatus results from a similar spectrograph with synchroscope, in which the responses of the cavity resonators are interpreted by means of a pulse method. The high performances of the apparatus render its use advantageous, not only as a spectrograph, but also as an accurate recording refractometer, as well as a direct-reading Q-meter.