Improvements in or relating to magnetic modulators of the second-harmonic type and apparatus for use in these modulators

摘要

872,786. Transformers and inductances. NATIONAL RESEARCH DEVELOPMENT CORPORATION. Feb. 27, 1959 [Dec. 24, 1957], No. 40029/57. Class 38 (2). [Also in Group XXXIX] A cross-field modulator giving a second harmonic output proportional to an input signal voltage or current comprises a hollow annular split ferrite core 1 containing a winding 5 energized by the input and an A.C. drive winding formed of a two-part conducting box 10A, 10B which surrounds the core and also acts as a screening container for it. The drive winding 10A, 10B is connected to an oscillator operating at the fundamental drive frequency and the signal source may be a thermocouple. The output is obtained either from winding 5 or from a separate concentric winding inside core 1. The output may be fed to an amplifier tuned to the second harmonic frequency.