SU1242876A1 - Device for phase-frequency calibrating of geophone channels - Google Patents

Abstract

The invention relates to the measurement of the phase-frequency characteristics of seismometric channels and can also be used for phase measurements during light-beam recording of vibrations. The device forms a short pulse signal with each amplifier passing through the calibration generator by means of the amplifier-limiter and pulse generator and sends this signal to the working galvanometer parallel to the signal under investigation. Thus, the initial phase marks are formed on the oscillogram, which allows to quickly determine phase shifts investigated processes. 2 Il. W tc N9 00

Description

The invention relates to geophysics, in particular, to obtaining the phase-frequency characteristics of seismometric channels with galvanometric registration, and can be used in other applied fields of physics, in which objects are measured by displacement, velocity and acceleration of objects using light-beam oscillographs. , .

The aim of the invention is to reduce the calibration time while simplifying the device.

FIG. 1 shows a diagram of an apparatus for phase calibration of a seismometric channel in FIG. 2 - signal, pulse, and trace plots. The circuit contains a generator 1 connected simultaneously to the calibration coil of the seismometer 2 channels connected to the operating galvanometer 3, and to the amplifier-limiter 4, which is connected in series with the driver 5 pulses, the output of which is connected through input 6 to The first terminals of the working galvanometer 3, The device operates as follows.

The signal from generator 1 is fed to the input of the coil of the seismometer 2 and causes a steady state. the harmonic oscillation mode of the mobile seismometer system, from the output of which the electric signal goes to the input terminals of the galvanometer 3. A part of the electrical signal from generator 1 is amplified and limited by amplification (glam limiter 4) is formed into a pulse of short duration by means of the transmitter 5 and consisting, for example, of a small capacitor, is fed to the input terminals of the working galvanometer 3.

The pulses can be formed on the leading edges of a limited signal of each harmonic period, and then on the recording of the working galvanometer, the moments of transition of oscillations are noted.

rez zero, serving as reference marks for the reference phase shifts.

The uniqueness of the measurement of the absolute value of the phase is determined by the well-known laws of the behavior of the phase characteristics of standard and non-standard seismometric channels used in the Unified Network of Seismometric Observations (ESSN USSR). Thus, for example, for a channel of the type SC, a phase transition through O and a change in the sign of the phase angle is expected for periods of the order of 2 С} П / 2 on periods of the order of 9 s and I for periods of about 17 s.

Additionally, the introduced circuit for phase calibration consists of a single microcircuit, consumes a current in units of milliamperes, and can be used at each seismometric station for monitoring and periodic channel calibrations.

Technical appraisal advantages of the invention consist in reducing by a factor of 2 the phase channel calibration time, simplifying the device due to the absence of an additional galvanometer and its illuminator and increasing the accuracy of reading one route up to 3-5% (compared to 7-10% of the known devices).

F-formula isob-reteni

A device for phase-to-frequency calibration of seismometric channels, containing an electric harmonic oscillator connected to a calibration coil of a seismometer connected to a seismometric channel galvanometer, is so that, in order to shorten the calibration time while simplifying the device , an amplifier-limiter, a pulse shaper and a decoupling circuit are introduced into it, while the generator output is connected to a series-connected limiter and shaper mpulsov, decoupling circuit and the terminals of the galvanometer.

figure 1

 f1 / g.

Editor N.Egorova

Compiled by M. Spassky Tehred M. Khodanych

Order 3700/44 Circulation 728, Subscription

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35 Raushsk nab., d, 4/5

Production and printing company, Uzhgorod, Projecto st., 4

Proofreader A. Obruchar

Claims (1)

Formula of the invention of which an electric signal is supplied to the input terminals of the galvanometer 3. A part of the electric signal from the generator 1 is amplified and limited by an amplifier-limiter 4, is formed into a short pulse by a shaper 5 and through an isolation circuit 6, consisting, for example, of a small capacitor, arrives at the input terminals of the working galvanometer 3. Pulses can be generated along the leading edges of the limited signal of each harmonic period, and then on the recording of the working galvanometer the moments of the transition of oscillations are noted. e with the fact that, in order to reduce the calibration time while simplifying the device, ilitel-limiter for42 tors, pulses and decoupling circuit, with the output of the generator is connected to the series-connected limiter-amplifier, a pulse shaper, isolation circuitry and the terminals of the galvanometer. figure 1