SU31311A1 - Device for multiple radio transmission by wire - Google Patents

Description

The present invention relates to devices for multiple radio transmissions by wire using currents of different frequencies acting on a cathode amplifier. The transmission of several signals through a single pair of wires has many drawbacks, such as the reverse action between the devices entering the device and induction between different circuits.

The main purpose of the invention is to provide a simple device for transmitting several signals with different frequencies or several signals of the same frequency from different sources over one pair of wires, with no induction between different circuits and interference between the signals. Another object of the invention is to ensure independence from each other of different circuits feeding one pair of wires.

These goals are achieved by using transformers that are electrically symmetrical with respect to the midpoint of their secondary windings, and using an equalizing line consisting of properly selected self-induction and capacitance, forming one arm of a bridge.

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Wheatstone, the other shoulders of which are composed of the adjacent halves of the divided windings and of the load.

In FIG. 1 and 2 are diagrams of the proposed device; FIG. 3 - modification of this scheme,

In the device (Fig. 1 and 2) all transformers J, 2 and 3 are electrically symmetrical, t, -e. The primary windings of these transformers are symmetrical with respect to the middle points 4, 5, and b of the corresponding secondary windings. The two halves a b of the secondary winding of the transformer 7 serve as adjacent shoulders of a balanced Wheatstone bridge. The third shoulder is the load consisting of a grid circuit and the lamp electrodes associated with it, and the fourth shoulder of the bridge is an equalizing line (A / i, chosen so that the footway is balanced. The equalizer line is shown in FIG. self-induction and capacitance connected in series, although it is obvious that it may contain resistance depending on the required degree of equilibrium. The end of the secondary winding from transformer 2 is connected to the middle point of the secondary winding of the transformer 7, forming the shoulder of the second meter hundred other three arms which are composed respectively of a first axle of the equalizing line NZ and part of a / the secondary winding of the transformer 2. It is evident that for the third transformer, the nearest to the battery voltage mix is not required equation "ytelnoy line.

The device shown in FIG. 1, is intended to combine the three frequencies (1, / 2 and / 3) and therefore no equalizing line is required between the secondary section of the transformer J and the load. However, if it is desirable to combine a larger number of frequencies, for example, four, then part g of the secondary winding of the transformer 3 is connected to the load by the bridge NS, as shown by the dotted line in FIG. 2. In this case, the bias voltage battery is connected to the middle point of the secondary winding of the transformer 4, which does not need a balancing line.

If there are equalizing lines NI and -ZVj, the currents caused in the secondary winding of the transformer 6 by one of the signals transmitted through this transformer will not give voltages in the primary windings of the other transformers, and therefore there will be no induction between the individual circuits. For example, the currents caused in both halves of the secondary windings of the transformer 7 by the signals of frequency / 2 are equal to each other and do not cause voltage to appear in the primary transformer /. The currents caused in both halves of the secondary winding of the transformer 7 by the signals / / 3 are equal to each other and do not create voltages in the primary winding of the transformer / 1. Similarly, it can be shown that currents caused by signals in frequency / 3 do not affect the voltage in the primary winding of transformer 2. Similarly, currents caused by frequency signals / I do not cause voltage in the primary windings of transformers 2 and 5 Thus, using the described device with bridges, it is possible to combine several signals of the same frequency or different frequencies without causing induction.

From the secondary windings of transformers, oscillations are fed to the grid of the lamp,

the anode of which is connected to the primary winding of the output transformer; Through the secondary winding of the last oscillation is transmitted to the wires 9.

In order to eliminate the possibility of an anodic circuit being reversed on the grid circuit, through the interelectrode capacitances of the lamp, and in order to facilitate the balancing of the bridge, a lamp with a shielding grid was used in the third load branch. However, it is self-evident that instead of a four-electrode lamp, one of the known types can be used in a bridge and a three-electrode lamp, and depending on the degree of equilibrium required, either one of the known methods of neutralizing the internal capacitance can be applied or not applied. . In some cases, for example, when combining low-frequency signals, neutralizing the internal capacity of the lamps is not required, while in other cases, for example, when combining high frequencies, it may be necessary.

FIG. 1, the voltage required for the anode and the shielding grid of the lamp 8 is taken from a common battery 7.

The main advantage of the described device, as compared with previous devices of this kind, is in the simplicity and efficiency of the design, in the use of only one lamp and in the elimination of the reverse action or induction between the circuits. Equating the apparent resistance of the transformer with the apparent resistance of the line, you can leave it constant and not change when the number of operating circuits changes.

FIG. 3 shows a modification of the circuit of the device of FIG. 1, 2. According to the circuit and operation, it is similar to the device of FIG. 1, 2 with the only difference that here two lamps are used, included in the push-pull pattern. As in the described device, the load is included in the third shoulder of each bridge, and the fourth shoulder is formed by the NI to NZI equalization lines, similar to the NI and L / a lines of FIG. 1, 2. Inductions between different circuits and interferences are prevented by means of equalizing lines NI and NZ, which must be chosen to balance the bridge.

As in the previous case, for the transformer closest to the bias battery / 7 ,, obviously, no equalization line is required. The equalization lines and may consist of a three-point apparent resistance, and the equalization lines N-i must balance the capacitance between the transformer wires and the capacitance between the line and the ground.

In addition to completely eliminating interference and induction between conductive paths, the embodiment of FIG. 3 has all the advantages inherent in the push-pull scheme, such as: eliminating the possibility of lamp overload and reliable operation, as in the case when one of the lamps stops working, the friend will continue to work, albeit with reduced efficiency.

The drawing shows low frequency transformers everywhere, however, in the case that high frequency signals are combined, high frequency transformers can be used. The device may be suitable for combining signals of the same or different high frequencies, signals of the same or different sound frequencies, or both.

Although a bridge is described here, in one shoulder of which a device with a linear characteristic is included, that is, A device that combines several signals without interference and induction between them.

but a device with a non-linear characteristic can also be included in the load arm of the bridge, such as with a heterodyne reception, where the oscillations of the high-frequency generator add up with the oscillations of the incoming signal. In some cases, for example, when using a device for combining high-frequency signals or heterodyne reception, the secondary winding of each of the input transformers must be tuned by means of a shunt variable capacitor. You can see that each of these circuits can be configured independently of the others, i.e. without changing the settings of other circuits.

The subject of the patent.

A device for multiple radio transmissions by wire using currents of different frequencies acting on a cathode amplifier, characterized in that the artificial lines NI, N2 ... and windings a, b, c, d, e, g of input transformers designed for frequency currents / i, / 2, fa ---, are included so that they form a Wheatstone bridge, in which the shoulder for frequency currents / „is formed by the input winding of the transformer for currents of this frequency and all the input windings of transformers for frequency currents / i Д ,, / 3 ... / (, (where n is an integer greater than one). to patent yn-noi f rmy .Radio Corporation Ayoriki Ns 31311

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