Abstract
The characteristics of G-M counter spectrometers are discussed. The must suitable type obtained for X-ray analysis is automatic recording one having a constant fractional standard deviation tank circuit. As shown in Figs. 5 and 6, if we intend to reduce the errors as low as 5%, the speed of rotation of a counter-tube must be reduced to nearly half of the constantRCtype, i.e. 3.6 degree/min. and 6 degree/min. respectively. But when only the peak values of reflected X-rays are required, considerably high speed of rotation will be used without serious obstractions.
