SU30459A1 - Electric seismograph - Google Patents

Description

The invention relates to an electrical seismograph, which is intended for geological surveys by a seismic method.

The mechanical seismographs used to date have low sensitivity and require for reliable recording of a large amount of explosives, reaching up to one ton per charge.

From the existing methods of electric recording of occupations, there is a known method in which the gravity changes the capacitance of an oscillating circuit with its movement. This effect, ultimately, translates into a change in electric current or voltage proportional to the displacement of the tandem. It is obvious that almost all circuits of electromicrometers and condenser microphones can be applied to this case.

A number of circuits built by Tgepdelenburg Backhaus and based on the principle of a condenser microphone are known. This circuit is well known and is a combination of two tuned circuits, one of which is a generator circuit and the other a receiving circuit connected with a detector lamp,

melting in anode detection mode.

In the proposed electrical seismograph, consisting of a generator and a resonant circuit, the capacitance of which is made so that it changes by seismic, according to the invention, so that the change in the rectified current while changing the oscillation period of the seismograph contours as well as by changing the grid displacement of the detector lamp, a resistance is included in the grid circuit of the generator lamp, the voltage drop on which is used as grid displacement for tector lamp.

In FIG. 1 depicts the scheme of the proposed electric seismograph; FIG. 2-4 diagrams explaining the operation of the device.

Oscillating circuit L, From the generator lamp L is connected with the oscillatory circuit L From the detector lamp L The grid of the generator lamp L, besides the coil Lg, includes a high-resistance alternating resistance Changes of a rectified detector lamp.

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FIG. 3