DE2653391C2 - Circuit arrangement for mapping electrical signals or functions with the aid of an electron beam oscilloscope - Google Patents

Description

The invention relates to a device for mapping electrical signals or functions with the aid of an electron beam oscilloscope provided circuit arrangement of a specified in the preamble of claim 1 Art

It is known, for example, from the publication “NTF 20”, 1961, pages 35 and 36, in particular to Several voltage curves or measurement curves converted into voltage curves for demonstration purposes simultaneously in a raster process on the screen of a black and white television receiver. With the raster method, a raster becomes more vertical and on the screen of a television picture tube horizontal lines are shown, and the voltage curves to be displayed are shown in this grid The voltage curves are differentiated according to the publication with different levels of brightness shown on the screen or a color picture tube is used.

From DE-OS 19 51 167 is a circuit arrangement known of the type specified. The known circuit arrangement has several transmission channels each of which includes a comparator circuit. Compare the comparator circuits an output signal of an input circuit that includes a device for shifting the zero position by means of a Has displacement DC voltage, with a high-frequency sawtooth-shaped deflection voltage and generate in the case of coincidence, an output signal that is converted into a keying pulse in a downstream pulse gate is converted. In the known circuit arrangement, the gating pulses reach another gate, which is controlled by a comparison circuit, which is derived from the lower frequency sawtooth deflection voltage a coincidence signal for the horizontal deflection and an even lower frequency sawtooth voltage generated. The gating pulses are sent from the last-mentioned gate to the modulator of the Picture tube of the circuit arrangement.

The invention is based on the object of the circuit arrangement of the type specified so train that even a larger number of signals and functions can be easily distinguished with simple means can be displayed on the screen of a color television set. This task is through the In claim I specified invention solved. Further education

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Fertilize the invention are specified in the subclaims.

The advantageous measure specified in claim 2, individual transmission channels by means of optocouplers to be galvanically separated from each other is actually from the magazine "Funk-Technik" 1975, issue 6, page 142 and 143, known for a channel switch that alternates between two measurement inputs and one measurement input of a single beam oscilloscope

The invention has the particular advantages that it has a large area and is therefore particularly suitable for demonstration purposes particularly suitable, colored representation of the oscillograms provides and that a Any commercially available television receiver can be used. The additional circuit may be required only to be accommodated in an additional device, so that the devices are extremely economical and can be produced cheaply. There is no camera. All inputs are absolutely potential-free and can Voltages, currents, characteristics, modulations and other desired functions always in the respective the same color. With the help of an internal product creator, z. B. the Reactive power can also be shown in a repeatable, characteristic color.

An advantageous embodiment of the invention is shown in the drawings and is in described in more detail below. Show it

F i g. 1 and 2 in a schematic block diagram a circuit arrangement for mapping electrical Signals and functions using an electron beam oscilloscope,

F i g. 3a, 3b, 3c, 3d diagrams to explain the Invention.

In the block diagram of FIG. 1 shows three transmission channels A, B, C of a circuit arrangement for mapping electrical signals and functions with the aid of an electron beam oscilloscope. Channel A is for example blue, channel B is for example red and channel C is for example green. However, further, similar transmission channels can be provided, which accomplish other, mixable colors with separate channels. All channels are designed in the same way, so that only channel A is described in more detail below.

Ar. the input of channel A is the quantity to be measured, e.g. B. an electrical signal applied. This arrives at an input amplifier la with an input divider or attenuator 2a. For the latter, for example, a step switch and / or a fine adjuster for / · coarse or fine attenuation is used, which allows the size of the display of the associated voltage to be set on the screen. The input voltage arrives at a stage 3a for galvanic isolation, which in the illustrated embodiment is designed as an optocoupler and comprises a bandwidth that starts from zero. In the exemplary embodiment shown, the stage 3a contains a light-emitting diode and a phototransistor and in this way achieves galvanic isolation for both AC voltage and DC voltage. A post-amplifier 4 is connected to the output of stage 3a, which compensates for the attenuation that occurred in stage 3a. It is an adding or operational amplifier and has the function of amplifying the output signal of the rod 3a and, moreover, of introducing a direct current component,

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fi5, for example, by means of an arrangement 4a, so that the zero position of the image can be selected. The comparison input 5a of an analog comparator 5 is connected to the post-amplifier 4. This changes its initial state when a signal at its signal input 5a exceeds or falls below a reference value at its reference input 5b.

To generate the reference voltage for the comparators 5 of the individual transmission channels, a line blanking pulse 2/4 / (Fig. 2) of z. B. 12 \ ls generated separately and integrated in an integrator 7 to a sawtooth. The sawtooth, which has a duration of 64 μ5 for one line, for example, is fed to the reference input 5Zj of the comparators 5. A voltage comparison takes place in the comparators 5. If the signal voltage is more positive than the reference voltage, the comparator generates a positive output voltage. However, if the signal is more negative than the reference variable, does the output of the comparator 5 generate a? negative voltage. When the signal passes above the reference voltage, a voltage jump occurs at the output of the comparators, which is designated in channel A by 8a. This voltage jump is differentiated in a differentiating element 9a designed as a /? C circuit and results in a blanking pulse 10a. A positive voltage jump in the comparator results in a positive voltage pulse, the duration of which determines the line width of the oscillogram, depending on the dimensioning of the ÄC element.

The channels B and C are designed in the same way and generate the blanking pulses 10ü> and 10c at their outputs. The pulses 10a, 106, 10c pass into a matrix circuit 11. Here, the electrical signals are assigned to corresponding voltage values which are suitable for controlling the color output stages of a color television receiver. Din channels A to C can be provided for any color, e.g. B. for the colors blue, red or green. But they can also be provided for all mixed colors that can be generated by z. B. several colors can be controlled together and thereby the desired mixed colors are generated.

A summing and subtracting generator 12 is provided for channels A and B in order to be able to add or subtract the voltages of these channels. Accordingly, a line 14 coming from channel A and a line 15 coming from channel B are provided to its inputs. In order to be able to display product voltages in addition to the total and differential voltages on the screen, a product generator 13 is provided which forms the product of the voltages in channels A and These voltages are also supplied via lines 14 and 15. A comparator 16, the mode of operation of which corresponds to that of the analog comparators 5, can optionally be connected to the sum or difference generator 12 or the product generator 13 via a switch 20. In this way, additional comparators can be saved. A voltage jump 17 generated by the comparator 16 is generated in the same way as the voltage jumps 8 of the comparators 5. A differentiator 18 corresponds to the differentiators 9 and the pulse 19 to the pulses 10.

Should a product or sum or difference aid be introduced from other channels

only the inputs have to be swapped accordingly or the channels accordingly from the outset to choose. The pulse 19 has a special color in the matrix circuit, e.g. B. cyan, assigned, since in the illustrated embodiment the basic colors already for the other channels are assigned and expediently a clearly distinguishable color is to be provided for this, whereby for example, the color television receiver test pattern can serve as an example.

The matrix circuit 11 is assigned a switch 11d. This allows the normal assignment of colors to be carried out in the Mal position, ie channel A the color blue, channel ß the color red and channel C the color green. When switching to position Ma 2, there is a certain different assignment, which corresponds, for example, to the standard colors of the three-phase current, ie channel A the color violet, channel R dir Farhr grlh and dom Kann) C the color green. There is thus a color swap in this case, in which z. B. instead of blue the sum of blue and red is formed, so that the control of the color picture tube results in a purple color.

The outputs of the matrix circuit M result in a red control at 21a, a blue control at 21b and a green control at 21c. These outputs can either be used to directly control the color output stages of the color picture tube of a commercially available color television receiver or the matrix outputs 21a, 216, 21c are used in a color television standard-compliant conversion to a composite video signal with subsequent AF modulation, and in this case via the antenna input of the color television receiver.

The lines 14, 15 and 22 of the channels AB C go to a trigger selector switch ABC shown in FIG. Here, the line 14 shown in FIG. 1 is connected to a contact A, the line 15 and to a contact C, the line 22. At the contact 23 there is also an alternating voltage which is phase-locked to the alternating voltage network. The outgoing line of the trigger selector switch ABC leads to a Schmitt trigger and pulse shaper 24. The voltages of any voltage form coming from the channels AB C are converted in the circuit 24 into a square-wave signal 25. In the circuit 24 there is also a selectable delay which, as an arrow 26 indicates, enables a horizontal image shift. The pulse sequence formed from the square-wave signals 25 forms the image synchronization signal for the receiver. Image blanking signals are formed from this pulse sequence of square-wave signals 25 in a circuit BAI. This consists z. B. from a monostable vibrator.

In a further pulse shaper stage 29 with a selectable delay, which is indicated by the arrow 31, is simultaneously generates a signal depicting a single vertical line 30 (Fig. 3b). This variable vertical line can be used as the ordinate in an axillary or as a so-called light pointer stick and can, e.g. B. for demonstration purposes, can be moved anywhere on the screen, such as is indicated by the double arrow 31.

Furthermore, an oscillator 32 is provided which serves as a mother generator. He is the mother generator for them Line sync pulses, the horizontal and vertical measuring grid lines. The oscillator 32 swings up twenty times the line frequency 20 fz. It works towards a frequency divider 33 with a division ratio of 1

ίο 20, d. i.e. it divides the frequency of the mother generator 15 625 Hz down. This pulse voltage passes over the line 34 to a line blanking pulse shaper 35 and a line synchronizing pulse shaper 36. At the oscillator 32, a second output is also provided, which is connected to line 38 via a differentiating element 37.

This circuit part is used to mark the in FIG. Yes shown horizontal measuring grid lines 39.

Via the line 34 (FIG. 2) is also one

lmniiUfnrmrr <irhaltiing 40 attached to Mr. Frrnnrnytrilrr Ϊ1 . The pulse shaping circuit 40 generates a single horizontal line as the center line 41 of the measuring grid (FIGS. 3a, 3b). The line 34 also leads to two frequency dividers 42 and 43. The frequency divider 42 contains a division ratio of 13 to 1, the adjustable frequency divider a division ratio of 3 to 1 and 2 to 1. This creates vertical measuring grid lines 44 (Fig. 3a) at a distance of 15 °, 30 ° or 45 ° based on 50 Hz and selected by means of a switch 45. The signals from the circuits 27, 28, 35, 36, 38, 40, 29, 42, 43 and 45 are combined in an adding circuit 46 to form a BAS signal. This either controls the first stage behind the video demodulator in the color television receiver, or it is operated in accordance with the FIG. 1 described alternative

j5 formed into a composite signal and then to RF modulation forwarded.

In Fig. 3a to 3d are some examples of the Arrangement according to the invention shown on a screen images of the electrical signals or Functions specified. 3a shows the three-phase components / 1, / 2, / 3 in an I5 ° grid, where for example / 1 = green, / 2 = purple and / 3 = represents yellow.

3b shows a representation for the current, voltage and power curves i, u, N. wherein the current curve is red, the voltage curve is blue and the power curve is cyan.

From Fig. 3c shows the superimposition of two channels. Here the curve f \ represents the voltage with the high frequency, the curve (2 the one with the low frequency and the curve / "3 the overlay of both. For example, the curve f \ blue-, the curve / 2 red and the curve / 3 cyan.

Fig.3d gives an example to illustrate an amplitude modulation, e.g. B. by means of multiplicative mixing. The high-frequency voltage HF can be shown in red, the low-frequency voltage NF in blue and the modulation or the product in cyan.

The circuits described can be carried out particularly advantageously if they are in one Attachments are built in and a standard color television receiver is used as a viewing device.

For this purpose 3 sheets of drawings

Claims (10)

Patent claims: 1.Circuit arrangement for mapping electrical signals or functions with the help of an electron beam oscilloscope according to the raster method, in which a corresponding number of inputs is provided according to the desired number of signals to be mapped at the same time, the input amplifiers (la, Ib, Ic, 2a, 2b, 2c ...) and zero position setting circuits (4a, Ab, 4c.) As well as a comparator (5 ...) for each channel with a downstream pulse circuit (9a, 96, 9c.), The outputs of which generate gating pulses characterized in that the channels (A, B, C ...) are each connected to an input of a matrix circuit (11), and that the matrix circuit is made up of the input signals (10a, 106, 10c ..., 19) with the aid of percentage evaluation circuits at its three outputs (21a, 21b, 2 \ c) for driving the blue, red and green color channels of a color television set, corresponding mixed voltage values are generated, so that each input of the matrix circuit has a bes timmte color is assigned to the color television tube 2. Circuit arrangement according to claim 1, characterized in that each channel (A, B, C ...) has a circuit for mutual and ground-side potential isolation (3a, 3b, 3c ... ), Preferably with the aid of an optocoupler 3. Circuit arrangement according to claim 1 or 2, characterized in that the pulse circuit (9a, 9b, 9c. ^ 18) is a differential element. 4. Circuit arrangement according to one of the preceding Claims, characterized in that from the signals in each case two channels simultaneously sum, Difference or product signals (product generator 13, or sum and difference generator 12) are generated, soft via at least one comparator (16) to light the picture tube depending on of a different color are switched via a matrix circuit (11). 5. Circuit arrangement according to one of the preceding claims, characterized in that a Integrator (7) from the line blanking pulses generated in the pulse part (FIG. 2) of the circuit sawtooth voltage generated (integrator 7), all comparators (5 ... 16) as reference signal serves. 6. Circuit arrangement according to one of the preceding claims, characterized in that in the matrix circuit (11) with the help of external switches (Ua, Hal, Ha2) certain color changes can be switched on. 7. Circuit arrangement according to one of the preceding claims, characterized in that a circuit is provided that the image, line blanking necessary for a color television receiver and synchronization pulses and additional vertical and horizontal (white) measuring grid lines in different selectable number, manually shiftable to TeU, generated and in an adder circuit (46) added to the BAS signal, which is after the video demodulator in the color television receiver is fed in. 8. Circuit arrangement according to one of the preceding claims, characterized in that the Output signals of the matrix circuit (11) and the Adding circuit (46) directly to the electrodes of the color television receiver picture tube or the color output stages and are fed behind the video demodulator, 9. Circuit arrangement according to one of claims 1 to 8, characterized in that the Output signals from the matrix circuit (U) and the adder circuit (46) to a color television standard-compliant Composite signal mixed, modulated onto an HF carrier and the antenna input of the color television receiver are supplied. 10. Circuit arrangement according to one of the preceding claims, characterized in that the signal conditioning circuit (Fig. 1) and the synchronous and raster pulse generation circuit (Fig. 2) are built into an attachment and a standard color television receiver as a viewing device is provided.