Primary radio-frequency standardisation by use of the cathode-ray oscillograph

Primary radio-frequency standardisation by use of the cathode-ray oscillograph

Author: Hazen, G. Frieda Kenyon, F.

Year: 1924

A method of high accuracy has been developed far the primary standardisation of radio frequency. Comparison is made between a tuning-fork of accurately known frequency with an electron-tube drive and a generating set of radio-frequency current by the use of two radio-frequency generating sets and Lissajous figures produced in a kathade-ray oscillograph. The apparatus used in this work consisted of a Bureau of Standards type R70B wave-meter which has a variable air condenser, 4 fixed mica condensers and 5 interchangeable inductors, a tuning-fork of 1024.2 cycles per second driven by a 5-watt electron-tube generating set, 2 radio-frequency generating sets each using a 250-watt electron tube, a kathode-ray oscillagraph having a tube of the cold kathode type requiring from 18,000 to 20,000 volts to operate. The Lissajous figures were formed on the Fluorescent screen by the alternating electric fields from two generating sets applied at right angle to each other and to the electron stream by means of condenser plates mounted on the tube. The procedure adopted was to adjust the second of the radio-frequency generating sets to a known multiple of the tuning-fork frequency by the use of th