Bridge Method for Studying the Spectra of Current Fluctuations in Tungsten Filaments in the Frequency Range 1.5·10–5–5·10–1 Hz

This article discusses the absence of methods for measuring low-frequency (LF) fluctuation processes at high temperatures and proposes an original bridge method for measuring the spectra of LF current fluctuations in the tungsten filaments of electric lamps in the controlled temperature range 300–2700 K. The application of the bridge measurement circuit reduces the influence of degradation processes in the filament and the power source’s own noise on the measurement results by several orders of magnitude. A spectral analysis of LF current fluctuations is performed in the frequency range 1.5·10 –5 –5·10 –1 Hz using an automated unit based on a personal computer under the control of specially developed software.