Resumo

LINDERO-HERNANDEZ, M.; ESPINO-HERNANDEZ, A.G.  e  ROMERO-BASTIDA, M.. Design and construction of a single-axis, low-frequency magnetic probe (B-dot probe) calibrated with a LC _var Helmholtz resonant circuit. Rev. mex. fis. [online]. 2019, vol.65, n.5, pp.560-565.  Epub 23-Abr-2020. ISSN 0035-001X.  https://doi.org/10.31349/revmexfis.65.560.

Magnetic probes (also known as B-dot coil) are electromagnetic devices used to measure magnetic field variations in many frequency ranges. The measured magnetic field frequency directly relates to the elected method to make the B-dot coil calibration. This work presents a B-dot coil calibration in a frequency range from 6.16 kHz to 36.63 kHz. An inductor L (Helmholtz coil) connects in parallel with a variable capacitor bank C var to form a coupled LC var resonant circuit. The LC var circuit is fed with a half bridge oscillator. The capacitance C var is varied until the circuit is in a resonant state at different frequencies. The resonant circuit produces sinusoidal oscillations in the aforementioned frequency band. The sensitivity is calculated by using voltage V out of the B-dot coil and voltage V H measured from Helmholtz terminals.

Palavras-chave : B-dot; Half bridge oscillator; LC _var resonant circuit; 07.55.-w; 85.70.Ay.