Volume 1, Issue 8, August 1930
Index of content:
1(1930); http://dx.doi.org/10.1063/1.1748714View Description Hide Description
A galvanometer system for the measurement of very small voltages, of the order of 10−11volts, is described and its application to the measurement of feeble radiations with a thermocouple discussed. It has been found that energies of the order of 1/200 of that previously detected by other devices could be measured with the Resonance Radiometer. The effect of the Brownian Movement on the system has been calculated and has been found to be about 1/200 that of the effect on the ordinary galvanometer.
An experiment is described for the measurement of the speed of action of thermocouples, and results on the splashed filament type are recorded.
1(1930); http://dx.doi.org/10.1063/1.1748715View Description Hide Description
Apparatus and methods are described by which time intervals may be measured to a precision of twenty microseconds. The duration of the time interval may be anything between twenty microseconds and ten seconds or even longer. The record obtained is continuous, making it possible to locate any event within the time interval to this same precision. The method is not limited to the measurement of electrical quantities. The application of the method to the determination of the speed of a rotating shaft is given in detail.
1(1930); http://dx.doi.org/10.1063/1.1748717View Description Hide Description
1(1930); http://dx.doi.org/10.1063/1.1748720View Description Hide Description