| 摘要 |
FIELD: medical equipment. ^ SUBSTANCE: device can be used in medicine for qualitative estimation of degree of pathological changes in tissues of throat and for differential diagnostics of different diseases. Device for measuring active and capacitive components of impedance of palate tonsils has pulse oscillator, input device connected in series with synchronous demodulator, permanent current amplifier and analog-to-digital converter, two 1: frequency divider, Schmidt flip-flop connected in series direct integrator, nonlinear converter of linearly/sinusoidal voltage, voltage-to-current converter, matching transformer, capacitive resistance converter, second synchronous demodulator, "active resistance-capacitive resistance" switch and indication unit. Error of measurement of impedance components can be successfully reduced within 500 Hz-10 kHz frequency range. Value of magnetization current of matching transformer can be reduced due to capacitive converter. Factor of harmonics of probing signal is reduced which is provided by probing of tested biological tissue by sinusoidal current. Active and capacitive components of impedance can be separated due to synchronization of phase-sensitive detectors by control pulses which pulses are shifter one relatively another for one quarter of period. ^ EFFECT: improved efficiency of measurement; increased precision. ^ 3 dwg |
