SU798597A1 - Crt-oscilloscope - Google Patents

Description

The invention relates to electrical measuring technology and can be used in real-time oscillography. The closest to the invention according to the technical essence is an electron beam oscilloscope, a two-position key containing sources of logic levels O and a controlled oscillator, a control unit, a vertical deflection amplifier with an adjustable gain factor, an electron beam tube, and a sweep voltage generator 1. The disadvantage of the device is a large balancing time. The purpose of the invention is to reduce the time of balancing. This goal is achieved by the fact that an electron-beam oscilloscope containing a two-position key, the first input of which is connected to the bus of the signal under study, the second input - with a source of logic level 1, the third input - with a source of logical level, O, the fourth input with a common bus, and the first output is with the signal input of the controlled attenuator, the control input of which is connected to the first output of the control unit, and the output to the signal input of the vertical deflection amplifier with adjustable gain controlling the the stroke of which is associated with the second output of the control unit,. and the first output is with Bet-THA-deflection plates of a cathode-ray tube, the horizontal deflection plates of which are connected to the output of a sawtooth voltage sweep generator, equipped with a clock generator, a pulse counter f with a decoder, and whose signal input is connected to the second output of the vertical deflection amplifier, the control input is to the third output of the control unit, and the output is to the first input of the sawtooth generator voltage-. nor a sweep, the second input of which is connected to the fourth output of the control unit, the first input of which is connected to the output of the decoder, the third input to the second, output of the two-position key, and the second exit to the second output of the clock generator, the first input of which is connected to the counter input to them, pulses, outputs associated with the inputs of the decoder.

The structural electrical circuitry of the device is shown in the drawing.

The device consists of a two-key switch 1, a controlled attenuator 2, an amplifier 3 vertical deflection with adjustable gain, an electron-beam tube CRT 4, a source 5 logic Level, a source logic level O, a control unit 7, a key 8, a generator 9 sawtooth voltage sweep, 10 clock pulse generator, pulse pulse counter 11 and decoder 12.

The device works as follows.

The signal under study arrives at the first input of the on-off key 1 and passes through the key 1, controlled by the attenuator 2 and the amplifier 3 to the vertical deflection plates of the cathode ray tube 4. At the same time, the logical level i from the output of the source 5 is fed through the key 1 and the control unit 7 to the control input of the key 8, which as a result of this opens, and the signal from the second output of the amplifier 3 is fed to the first input of the generator 9 of the sawtooth voltage sweep and starts it. An image of the signal is observed on the ELG 4 screen. In this case, the transfer coefficient of the attenuator 2 and amplifier 3 is set in accordance with the amplitude of the signal under study, the voltages supplied to their control inputs from the outputs of the control unit 7.

When balancing, the on-off switch 1 is shifted to the second position, in which the input of the attenuator 2 is connected to the common bus, and at the output of the amplifier 3 there is only an imbalance signal. At the same time, the logic level from the output of the source 6 is fed through the key 1 and the control unit 7 to the control input of the key 8, which as a result is closed.

Clock pulses from the output of the generator 10 begin to flow through the control unit 7 to the second input of the sweep generator 9 and start it. These pulses are also fed to the input of a pulse counter 11 with a conversion factor equal to the number of oscilloscope deviation coefficients, t, e, the number of possible combinations of attenuator transfer coefficients 2 and amplifier 3, Counter 11 counts the clock pulses continuously, and the operation is cyclical.

Each state of counter 11 is converted by decoder 12 into a parallel co / - ,. The pulses of this code pass through the control unit 7 to the control inputs of the attenuator 2 and amplifier 3, as a result of which sequential switching is performed

the frequency-compensated attenuator dividers 2 and the circuits determining amplification of amplifier 3; All oscilloscope deviation coefficients are switched sequentially in order of their increase (or decrease) with the frequency of the clock pulses. This frequency is chosen as 1-2 kHz so that the switching of the deviation coefficients is not perceived by the operator as a flicker on the screen. On a CRT 4 screen, a family of horizontal lines is observed, the number of which corresponds to the number of discrete oscilloscope deflection factors. The distance of each of these lines from the zero horizontal mark of the CRT 4 screen scale is proportional to the voltage unbalance of the amplifier 3 vertical deflection. Watching the CRT screen, the operator turns the tower controls. If the elements of the adjustable cascade are intact and if the amplifier is not balanced due to mutual compensation of the rebalancing of one cascade by another, then the horizontal lines are collected in a narrow beam on the zero line of the screen scale, grouped into one line.

The proposed device can reduce the time spent on adjustment, increase productivity.

Claims (1)

1. US patent No. 3582807, CL.- H 03 G 3/20, 330-45, 1971 (prototype).