Volume 3, Issue 5, May 1932
Index of content:
3(1932); http://dx.doi.org/10.1063/1.1748927View Description Hide Description
This paper describes an oscillator which makes use of the fact that the four element vacuum tube may have a negative internal resistance under certain conditions. The oscillator is capable of frequency variation over a wide range by the variation of this negative internal resistance.
3(1932); http://dx.doi.org/10.1063/1.1748928View Description Hide Description
Resistances of from 1×108 to 3×1010 ohms have been obtained by sealing capillary bridges (inside diameter 0.005 to 0.088 mm) between calomel electrodes made up with dilute KCl—saturated calomel solutions. These resistors can be used satisfactorily with an electrometer or sensitive galvanometer and condenser set‐up. They do not exhibit polarization and their resistances do not change with age. The temperature coefficient is that of the KCl solution used in the preparation of a resistor.
3(1932); http://dx.doi.org/10.1063/1.1748929View Description Hide Description
Three electroscopes are described whose electrodes are: (I) a single fiber repelled from a forked wire, (II) a Schonland electrode hollowed to increase the sensitivity, (III) a Schonland electrode, also hollowed, but with the mirror hung on a singlegold leaf suspension and rotating on a nearly vertical axis. The deflections produced by the emission of an α particle, as a consequence of which about 105 ions were collected, were approximately: for type I, 5 eyepiece scale divisions; type II, 7 mm; type III, 20 mm. A method is given for determining the charge sensitivities of certain electroscopes.
3(1932); http://dx.doi.org/10.1063/1.1748930View Description Hide Description
3(1932); http://dx.doi.org/10.1063/1.1748931View Description Hide Description
3(1932); http://dx.doi.org/10.1063/1.1748933View Description Hide Description