Improvements in or relating to electrical devices for testing the functions of living bodies

Abstract

Abstract 618,405. Capacitance measurements. ROSA, L., and ZAKARIAS, I. May 9, 1940, No. 8372. Convention date, May 10, 1939. [Class 37] A device for testing organs of the body which comprises a tuned circuit detunable by the organ to be tested by one or more electrodes near the organ, is characterised in that a self- or externally-excited circuit is connected to one control electrode of an electronic valve having two control electrodes, the other control electrode of which is connected to another tuned circuit, and in that the fluctuations of the main or auxiliary anode and/or screen grid current of the valve caused by detuning of the first tuned circuit is evaluated by an indicating and/or recording device 20 which is connected, preferably by means of an amplifier, to the valve. As shown, the cathode 2 and the triode grid and anode 3, 4 of the triode-hexode valve 1 are connected to a tuned circuit comprising an inductance coil 5 and a variable condenser 6, the second control grid of the hexode being connected to the grid of the triode. Oscillations generated in this circuit excite a second tuned circuit comprising inductance coil 17 and condensers 16, 18, the organ to be tested being placed adjacent to or between the electrodes of condenser 16 or adjacent to the inductance coil 17. The valve is supplied from the mains through at least two stages of voltage stabilization. The valve of the octode type may alternatively be used.

Inventors

No inventors recorded.

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