SU117640A1 - Electronic recording apparatus - Google Patents

Description

The invention relates to apparatus for simultaneously registering by a spark, thermoelectric or electrochemical method a large number of different processes on a wide paper tape passed between two electrodes, with the possibility of simultaneously observing these processes on the screen of a cathode ray tube.

The electronic recording apparatus can be used in medicine, technology and in phototelegraphic communication as a multi-channel recording device while simultaneously recording many processes with a frequency from 0 to 1000 or more trans / sec.

Existing known devices for registering various processes have limited ability to simultaneously record trimer up to 5-6 processes.

The described apparatus eliminates this drawback and can register a large number of different processes.

The drawing is a block diagram of an electronic recording apparatus: / - amplifier and voltage comparator; 2 - linear sweep generator; 5 - synchronizer and generator of pointed impulses; 4 - pulse switch (in it A is a common electrode, B is a comb, and B is a TG-1B tiratron); 5 - straightener. Input amplifiers and a tape device are not shown in the diagram.

The voltage comparator has input amplifiers, the number of which is equal to the number of voltages under study, and a linearly increasing voltage amplifier.

At the moment when the voltages are equal at the anode of one of the input amplifiers, a short square wave pulse / 2 "

For each course of a linear sweep in the comparator, pulses appear in an amount equal to the number of input amplifiers; impulses

No. 117640

amplified by the power amplifier, are fed to the register electrode. At the same time as the start of the linear sweep, the generator generates a synchronization pulse ts, which is amplified, formed into a rectangular one and arrives at the delay line. A rectangular pulse passes the delay line during the rise time of the sweep generator voltage ti.

The duration of the pulse that arrives at the delay line 4 should be / 4 where n is the number of comb electrodes.

Each section of the delay line is attached to the thyratron mesh. Before the pulse arrives at the grid, the thyratron is closed.

At the time of the appearance of a pulse, the thyratron, whose grid is under the potential of Uf4, conducts a current and a point is registered on the paper against the corresponding comb needle.

In addition to a hot cathode of the TG-1B type, a cold cathode thyratrons, as well as semiconductor triodes, which can pass a short current pulse of up to 100-150 mA, can be used as a controlled relay.

With the use of a controlled relay, the number of input recording channels is unlimited.

For small quantities of simultaneously recorded curves, the circuit can be applied without a relay, and in this case pulse / 2 has a negative polarity, pulse 4 is positive. With the passage of a pulse of the delay line through the electrodes of the comb (in series with which the limiting resistance is switched on) a weak current passes which does not leave a noticeable mark on the electrochemical paper or is below the sample potential of the metallized paper. At the time of the appearance of pulse 4, the current through the electrodes of the comb increases and a point from the pulse remains on the paper.

Instead of a delay line, a sequential switching trigger circuit can be applied to semiconductor triodes, in which only one trigger cell can carry current at a time.

The trigger circuit can be switched by sequential self-starting with an initial synchronizing pulse 4 or from a separate generator with a frequency

For an electronic recorder with a delay line of 20 micron / s, with a discrete recording of 40-50 points per period, the maximum

the frequency of the recorded curve can be fmax T) taking

About 8 / pa3e- i- at 1 20 μsec, we will have - YuOO per / sec., With

In this case, the frequency of the sweep generator or the frequency of the signal decomposition corresponds to - 40000 per second

The actual resolution of the electronic recording apparatus is determined by the resolution for the applied electrochemical or metallized paper and is approximately 5 m1 s, which corresponds (at a comb needle diameter of 0.2 mm) to a signal decomposition of 25,000 pulses / sec. By increasing the current in the pulse, it is possible to increase the frequency of decomposition to 40,000 pulses / sec.

f t, n