DE892605C - Electrical transmission system for non-sinusoidal vibrations by means of pulse code modulation - Google Patents

Description

The invention relates to transmission systems for non-sinusoidal vibrations, such as Speech, music, sound, mechanical vibrations and image transmissions, which are carried out at great speed transmitted code groups are used, with all code groups having the same number of impulses and the impulses are of two different types.

The invention is to provide a transmission system with the non-sinusoidal Vibrations with high fidelity can be transmitted so that the signal-to-noise ratio of the received signal is significantly greater than the signal-to-noise ratio in the transmission channel, whereby the bandwidth required for the transmission is kept as small as possible at the same time will.

Another object is to find improved and simplified methods and devices for the transmission of signal pulses over a channel with a low signal-to-noise ratio and to achieve signals with a large signal-to-noise ratio.

In particular, one object of the invention is to provide methods, circuits and devices create in order to transmit pulse groups one after the other over an existing channel, which the Represent instantaneous amplitudes of the vibration to be transmitted.

Another object of the invention is an improved device for determining a transmission code, with which a large number of different amplitude values can be displayed without complicated counting circuits and the like.

■ An object consists in converting a pulse train, which represents the instantaneous value of the transmitted vibration, into a single pulse, the amplitude of which is one at each instant. Function of the amplitude of the original oscillation is ..
Another subject is the composition of the individual amplitude values so that essentially the same oscillation occurs at the receiver as was sent at the transmitter.

One feature of the invention relates to methods and apparatus for determining an electrical Value and for the transmission of a pulse sequence characterizing the value.

Another feature relates to methods and devices for producing an electrical value, which is a measure of the instantaneous amplitude of the vibration to be transmitted. This value can have the form of a conductance.

Another feature relates to methods and apparatus for staging this electrical value by adding and removing, the final value being a function of the to transmitted vibration is.

Another characteristic relates to conductance values from which by adding and removing the desired final value arises.

Another feature concerns the transmission of a code indicating whether a conductance has been added or removed.

Another feature relates to methods and means of receiving for decryption and to convert the transmitted code so that an oscillation is obtained at the end that reproduces the original vibration with high fidelity.

Other features concern the synchronization and collaboration of the various Circuits and facilities in the transmitter and in the receiver to ensure the correct working of the whole System.

According to the invention, a device is first provided that a sequence of control pulses with certain temporal sequence generated. The control pulses are used to control a Code device used, which in turn generates a series of short pulses, of which some are positive, some are negative, and some are positive and negative. There is also a device that determines an electrical value which is a function of the instantaneous amplitude of the Vibration is. This device is also controlled by the pulse generator. at The code device generates a sequence of code pulses for each control pulse. These code pulses together with the device for determining the instantaneous amplitude provide an electrical one Value, the size of which depends on the amplitude of the vibration to be transmitted at the time of the control pulse depends. In the present invention, said electrical value is Form of damping that is gradually changed by reducing it to the instantaneous value of the Vibration acts and after a damping change by the residual value so is controlled so that the next change is determined. The electrical value has the form of a master value, which consists of several master values of different sizes, which are inserted or removed, so that a combination is created, the conductance of which corresponds to the amplitude of that to be transmitted Oscillation at the time of the control pulse. The conductance affects the instantaneous amplitude so that it is reduced to a residual value which is only a fraction of the original Represents amplitude. The residual value is checked in stages, with the change in conductance ever smaller wind. At each level and within certain limits, it is determined whether the residual value above or below a certain reference level. If z. B. the conductance after a change is so great that the residual value is below the reference level, the last The change is reversed, but if the residual value is above the reference level, it remains, and the next smaller change is tentative performed. This process continues. If the size of the master value after the last change a residual value of the vibration to be transmitted that is smaller than an arbitrary one Is the reference level, the last added conductance element is removed so that the Residual value is at or close to the reference level. If the last change has a residual value above of the reference level, the master value added last remains switched on. The message, that an added conductance remains in the circuit becomes a receiving station given that no signal is transmitted, while the message that a conductivity has been added is removed again, is transmitted by a signal. This message is given by the time to which the signal is transmitted or not transmitted, more precisely identified. These Type of comparison of the instantaneous amplitude with the conductance in the 'circuit can be gradual as far as desired and until the accuracy of what is reproduced on the receiver Signal meets the intended fidelity.

After a pulse code has been produced in this way, which shows the instantaneous amplitude of the fully identifies the transmitted vibration, this pulse code is sent. Since the Instantaneous amplitude. is fully defined by the combination of the impulses, the needs Receiving device initially only determine the type of each pulse, i.e. whether it is a yes or a no-impulse. A yes impulse is an actual electrical impulse, while a no impulse means that no impulse is actually transmitted. As long as the received pulses are so far above the interference level that the receiving device has its type can precisely determine their origin and form

of the pulses and other distortions in the transmission path including any amplifiers no or only little influence, since noise and distortion are the code combination Don `t change. In the receiving station are a pulse generator, a code device and a System of master values to be inserted or not to be inserted, which correspond to the elements in correspond to the sending station. In addition, the

ίο receiving station has a decryption device, in which the received impulses are used to generate an electrical value, the direction and size of the value of the instantaneous amplitude of the to be transmitted Corresponds to vibration in the transmitting station. The vibration to be transmitted is in the receiving station recovered from the successive instantaneous amplitudes.

The invention, both in its construction and in its operation, will be as well as theirs further tasks and features on the basis of the following description and the drawings become easier to understand.

Fig. Ι and 2 show the components in a block diagram an embodiment of a message system according to the invention and Art their interaction;

Figures 3 and 4 illustrate the nature of the impulses in such a system and the timing of their occurrence dar;

Fig. 5 explains the method and the devices used for measuring and determining the instantaneous amplitude a non-sinusoidal oscillation are used;

Figures 8-13 give the details of the various Circuits and devices of an embodiment of the invention again when they are placed together in the manner shown in FIGS. 6 and 7;

Fig. 14 shows how a part of Figs. 9 and 10 is modified can be.

In Fig. Ι S is a source for modulation signals that represent a non-sinusoidal oscillation, for. B. a speech, sound, telegraphic, 45 or video radio oscillation, a small part of which is shown by the curve 301 in FIG. It should be noted that curve 301 gives only a very simplified representation of an actual part of such an oscillation for the purpose of explanation. An encryption device or modulator sends out a sequence of signals which follow one another at times t _m , t _{m + 1} , t _{m + 2} etc. and which, in the exemplary embodiment of the present invention, have the same time interval T as in FIG. 3 is given above. The time intervals T depend on the highest frequency occurring in the oscillation to be transmitted. The frequency of the time intervals is usually at least twice as great as the highest frequency of the oscillation. If the vibration z. B. contains a maximum frequency of 4000 Hz, the time interval is about 125 μ $ or less. Each sequence of signals consists of a pulse group containing η + ι code pulses of the yes-no type, where η can be any positive integer. Such code pulses only differentiate between two states, which are denoted by yes and no. These can be temporal states, frequency or amplitude states ¹ . In the present exemplary embodiment, there are amplitude states, the transmission of a pulse representing a yes pulse, while the absence of a pulse means a no pulse. In the invention, the first signal of the code pulse group is used to identify the polarity at the time of determining the instantaneous amplitude of the oscillation, a yes pulse or a pulse with a finite amplitude being negative polarity and a no pulse or a pulse with zero amplitude indicates positive polarity. The following w signals of the code pulse group describe the magnitude of the oscillation 5 ¹ at the time in which the instantaneous amplitude of the oscillation was determined. However, these pulses are transmitted after the instant of determination of the instantaneous amplitude and in successive times during the time segment T up to the first pulse of the next sequence of signal code pulses. These »signals can be of such a nature and composition that they can be used in a large number of. represent different amplitudes (advantageously as a binary system, as it is described here as an example). If eight pulses are used in each code group, a total of 256 different combinations of yes and no signals can be sent during the time period T between successive determinations of the instantaneous amplitude. It is assumed that in the time segment T ₁ which _{follows f m + 3} in FIG. 3, the transmitted combination reads yes-yes-yes-no-yes-no-yes-no. The first yes signal of this example transmits the message that 6 ¹ has negative polarity at time t _{m + s.} The other signals transmit the message that the amplitude of 5 "at time t _{m + 3} 2i units is above the specified reference level, assuming the conductance levels G ₁ to G ₇ as given in the table below (G ₃ -IG ₅ -IG ₇ = 16 + 4 + 1 unit).

A special means of achieving such signal sequences is shown in block form in FIG. First, the overall effect is described and then the nature of the individual Parts.

Even if the functions described can be carried out without frequency conversion, the basic problems are simplified by the fact that the modulation signal "S" is first fed to the push-pull modulator I in FIG. ₀ , which is high compared to the frequencies occurring in signal S. At the point in time at which the instantaneous amplitude S is to be determined, for example at time t _m in FIG is to be designated, from the pulse generator VI

the push-pull modulator I transmitted. During the period T between t _m and t _{m + v} until another iW pulse reaches the modulator I, the modulator output current I _{m has} the frequency ^ ₀ and an amplitude that is proportional to the instantaneous value of S at time t _m. It is positive if »S * is positive at t _m (see 302 and 303 in FIG. 3), and negative if 5" is negative at t _m . At t _{m + 1} , another instantaneous amplitude of the oscillation is determined. In the next time segment T , the modulator output has the same frequency but a new amplitude, e.g., 3O2 ₁ and 3O3 _x in Fig. 3. In Fig Line 303 shows the vibrations with the frequency f ₀ belonging to the successive instantaneous amplitudes of 5 ". It should be noted that when 5 "becomes negative, for example at t _{m + 3} in FIG. 3, line 3O2 ₃ , -this is represented by a reversal of the phase of the current modulated _{with frequency / 0, as in FIG} Shows line 3033.

The current I _m goes to a homodyne detector IV to dom the conductance devices III, which consist of the conductance values G ₁ , G ₂ ... G _n , as shown in detail in FIG. The oscillator II also outputs power to the detector IV. At the output of the detector IV a voltage or a current is obtained which increases with increasing 6 ", which is negative when 5" is negative, and which is positive when S is positive. However, this output need not be proportional to S. The output of the detector IV goes to a polarity and amplitude detector V. This serves two purposes: 1. After an M-pulse at the time an instantaneous amplitude is determined, e.g. B. at t _m , arrives at modulator I, and after a reset pulse, which will be described later, brings all conductance of III to a minimum, a pulse goes to V. If the polarity is negative at such a time, the detector V given an impulse to the transmitter VII. This causes the transmitter to emit a yes signal, preferably in conjunction with a pulse from the pulse generator VI.

If the polarity of 6 "at such a time is positive, the detector V does not give a pulse to the transmitter VII, so that this does not have a signal emits, which means no, or a pulse from the generator VI causes the transmitter VII to deliver a no-signal. 2. The detector II is used to measure the output of the homodyne detector W and for the corresponding control of the tail units III, as described in detail later will.

The conductance values G ₁ , G ₂ ... G _n are electrically controlled and have yes and no states, corresponding to the digits and units of the binary 'numbers, the level of 6 ¹ at the time of the instantaneous amplitude with respect to an arbitrary level represent. In the above example, with ι + η = 8, the entire conductance is described by seven units. If the various conductances are inserted or removed, the overall conductance is changed by the amounts listed below.

Change by G ₁ 64 G ₀

- G ₂ 32G ₀

- G ₃ 16G ₀
-G ₁ . 8G _n

- G ₇ G ₀

where the conductance G _{0 is} relatively large compared to the smallest tail unit G _{m of} the circle, ie G _m <^ G ₀ . Otherwise the entire master value range goes from G ₀ to 127 G ₀ in steps of G ₀ . This gives a range of about 42 decibels in relation to the lowest level. The conductance values G ₁ ... G _n are electrically controlled by the control circuits (C ₁ , C ₂ ... C _n in FIG. 9), which are fed a) by the pulse generator VI and b) by the amplitude of the polarity and Amplitude detector V. In Fig. 4, the type of these pulses and the time of their occurrence are shown. The figure shows the time segment T between the instantaneous amplitude pulses or the time required for a work cycle, expanded over time. The second time segment of FIG. 3 is shown. The negative part of the Af pulse stops the modulator I, and the immediately following positive part picks up the instantaneous amplitude of the oscillation. At the same time, the initial negative impulse, which is shown for each of the lines 1 to η , changes all conductance values to the state with the lowest conductance value. In the meantime, the instantaneous amplitude of the oscillation works on the homodyne detector IV.

Thus, a "reset pulse puts all conductance values at t _{m + 1} into the state with the lowest conductance value. Then a polarity pulse P arrives at the polarity and amplitude detector V, so that the polarity of 5 at t _{m + 1} is transmitted by the transmitter VII. 4, a positive pulse is then applied to conductance G _1. This changes the overall conductance by switching on 64 G _0. Immediately thereafter, a negative pulse is applied to conductance G _1. If, after switching on the conductance G _1, the remaining amplitude at the output of the homodyne detector IV is still above the reference level despite the reduced current at the input of the detector, the state of G ₁ does not change and the conductance remains switched on No pulse to the transmitter VII, so that either no signal is sent, which means no, or a certain no signal is generated by an emanating from the pulse generator VI Sent out impulse. If, however, after switching on the conductance G _1, the amplitude "falls below the reference level, the conductance is removed by the negative pulse applied to it. At the same time, a pulse goes to transmitter VII. This causes the transmitter to be sent with or without a pulse from pulse generator VI , but preferably with one

Impulse to send a yes signal. Thereafter, positive and negative pulses are successively applied to the conductance values G ₂ ... G _n in channels 2 ... η , whereby either these conductance levels are switched on-S and no signals are transmitted, or the conductance levels are switched on and then removed and a yes signal is transmitted. After η + ι signals to determine the polarity and instantaneous amplitude of

If S are sent out, the pulse generator VI sends a reset pulse to the conductance values so that they are all brought into the state with the lowest conductance value. This pulse causes the transmitter to send out a marking or synchronizing signal, which indicates the end of a period and the beginning of the next. The pulse is also the negative pulse that is applied to the modulator I.

In order to describe the system, it is useful to refer to further details of FIGS. 3 and 4, which show the shape and the time interval between the pulses to be supplied by the pulse generator VI. At the top of FIG. 3, a sequence of pulses is drawn which go to the modulator I via the channel M , and also an amplitude section 302 of the oscillation 301 at the moment when a modulator pulse occurs. With the help of the electrical switching elements, the amplitude piece causes the modulator to output a current Iα with the frequency / ₀ and the amplitude of 6 * at the time at which the instantaneous amplitude was determined until another pulse occurs.

This is shown on the second and third lines 302 and 303 in FIG. 3. A polarity pulse that goes to the polarity and amplitude detector V comes a moment later. This pulse is followed by the pulses in channels 1, 2 ... n, which act on the conductance values G ₁ , G ₂ ... G _n . In addition, a pulse channel T to the transmitter may be necessary, as shown in FIGS. 8, 9 and 10, namely when the no signals are transmitted and not only result from the omission of the signals. All of this is shown in FIG. 4, which, as already stated, shows a working cycle extended over time, starting at t _{m + 1} . At the time of the M pulse, channels 1 to η receive strong negative pulses from the pulse generator VI, whereby the conductance values are brought into the state of the lowest conductance value. The polarity and amplitude detector then receives a pulse P. This sends a pulse to the transmitter VII if the polarity of the instantaneous amplitude of the oscillation is negative, and a yes signal is sent from the transmitter to the receiving station.

If the polarity is positive, no pulse goes to the transmitter and a no signal goes from the transmitter to the receiving station.

The w control channels receive pulses one after the other, first a positive and then a negative. The positive pulse switches on conductance, the negative removes conductance when the attenuated output of the homodyne detector IV has fallen below the reference level and sends out a yes signal, otherwise the conductance remains switched on and a no signal is generated. As shown in FIGS. 8, 9 and 10, pulses are always sent to the transmitter via channel T , regardless of whether a yes, no or marking or synchronizing signal is to be sent. These pulses naturally result in a no signal in the transmitter, but together with pulses from the conductance values G ₁ ... G _n or from the polarity and amplitude detector V they result in a yes signal.

The explanation of the 'transmitting station of the invention System will now be carried out with reference to FIGS. 8, 9 and 10, in which the various Block components with the same Roman numerals as in Fig. 1 are designated. the Non-sinusoidal vibration to be transmitted is fed to a push-pull modulator system I. This vibration can be terminated by any suitable terminator 806 Source come from e.g. B. from a microphone 805. It is then periodically divided and a process subject, which will now be described in more detail.

Pulse generator VI

It will be advantageous now to use the pulse generation system VI, which is shown in detail in one form in FIG. That The first control element of this part of the overall system is a relaxation oscillator with a gas-filled tube 1010. This relaxation oscillator is known. It contains a resistor 10111 for charging a capacitor 1012 from battery 1013. Assuming that the capacitor is discharged at the beginning, it is charged when the circuit is closed, the time of charging is determined by the resistance ion. If the potential of the capacitor and thus the anode of the tube 1010 has risen to the ignition voltage, the capacitor is suddenly discharged through tube 1010 and resistor 1014. The duration the discharge is short. There is a steep positive pulse at resistor 1014. The duration this pulse and the time sequence of the pulses can be controlled by the switching elements of the no Are regulated, in particular by the. large resistance ion, the capacitor 1012, the battery 1013 and the resistor 10114, as well as by the grid voltage of the tube 1010 set by potentiometer 1015 can be. Any other type of toggle switch can also be used at this point, however, the one shown is simple and sufficient.

The positive pulse on resistor 1014 is used to control the sending of pulses to different parts of the circuit. this happens by adding a delay circuit 1016, which is made up of similar inductances and capacitances consists of a ladder arrangement, to which resistor 1014 is connected. The positive impulse goes through the network, with the

Times when the impulse arrives in the individual chain links are evenly spaced. Corresponding positive pulses result in channels i, 2 ... n, the purpose of which will be described later. The delay network is terminated by the load 104.01, which is of such a value that reflected pulses do not occur. The switching elements of the relaxation oscillator can be dimensioned so that pulses with any desired frequency are generated at the resistor 1014. For the present invention, a frequency is preferably used which is higher than the highest frequency that occurs in the non-sinusoidal oscillation to be transmitted. If it is z. B. speech vibrations and all frequencies up to 4000 Hz are to be transmitted, at least two instantaneous amplitudes per period of this highest frequency should be determined. A suitable value for the sweep frequency is therefore 8000 Hz, but higher values can also be used.

With the help of the delay circuit 1016, positive pulses are available at the connections of the chain links, which are the same as the pulse at 1014 and which have a time interval that is determined by the switching elements of the chain links of the same type. At time t _m , when the pulse occurs across resistor 1014, it is transmitted to tube 1020 immediately. From there it goes as an M or instantaneous amplitude pulse according to FIGS. 3 and 4 to the modulator I, wherein it has positive and negative parts which are produced by the transformer 1019. The function of this pulse is described below. A time segment later, the impulse emanating from 1014 has reached point P on the first element of the delay circuit 1016. Now it is called the P-pulse. This P-pulse goes to the grid of the tube 1021, creating a positive pulse at the resistor 1022, which is transmitted to the polarity and amplitude detector V, where it appears as a positive pulse of the shape and at the time as indicated by the line P in Fig 4 is shown. The positive pulse M emanating from 1014 arrives at points 1, 2 ... η of the elements of the delay circuit 1016 at successive time intervals. These pulses are transmitted to the grids of tubes 1081, 1082, 1083, etc. Each pulse is transformed on its further path into a positive and negative pulse, as shown on lines 1, 2 ... η in Fig. 4, the nature and purpose of which will be described below.

In addition to these impulses, a group of impulses should be set according to the above. M, P and i, 2 ... w pulses are transmitted to the transmitter VIt. These impulses are called T-impulses. They are shown on the lower line in FIG. It should be noted that the first pulse of this group, which corresponds to the M pulse, is longer and has a greater amplitude than the subsequent ones. The reason for this will become clear later. The first pulse can e.g. B. be twice as long and twice as high as the following. Tubes 1024 to 1029 are used to generate the Γ pulses. The M-pulse reaches the grid of the tube 1024 directly. In the cathode circuit there is a parallel connection of resistor 1031 and capacitor 1032. A positive pulse is produced at resistor 1031, the duration of which would normally be the same as that of the M pulse. However, this pulse is lengthened by the capacitor 1032, the capacitor being chosen so that the pulse duration is approximately doubled. The positive pulse at 1031 goes to the grid of the tube 1025, the cathode circuit of which contains the resistor 1030. From here, a positive ^ pulse twice the length of the M-pulse is transmitted to the transmitter via the T-channel at the time of the occurrence of the M-pulse on the delay circuit 1016. The relative size of this pulse can be controlled by adjusting resistor 1017 upstream of the delay circuit. When the positive pulse from 1014 successively reaches the points P, 1, 2 ... η of the delay circuit 1016, the grids of the tubes 1026 to 1029 · pulses, so that positive pulses arise at the cathode resistor 10130 common to all tubes 1025 to 1029. In this way, the desired sequence of positive pulses is given to the transmitter VII, as shown on the lower line in FIG. In order to synchronize these pulses with the rest of the device, delay circuits can be switched on if necessary. Such a circle 1050 is shown in the T-channel.

Corresponding to the M and P pulses, the number of elements of the delay circuit 1016 is usually made equal to the number of digits required to construct the amplitude code sent by VII. If η digits are to be present, the number of possible codes resulting from the permutation of yes and no signals is 2 ". If the number of digits of the code is seven, 128 combinations are possible so that the system is capable to distinguish between 128 different amplitude values.

A circuit consisting of the tube 1061 and the transformer 1071 is connected to the conductor 1 of the delay circuit 1016 and the tube 1081. The tube 1061 is shown as a double triode. The grid of the left system of this tube receives a relatively large positive pulse at time t _m , which results in a negative pulse at the anode. This negative pulse is transmitted via the transformer 1071 as a negative pulse for controlling the corresponding conductance value G ₁ in FIG. 9 and serves to put this conductance value into the state with the lowest tail unit, as will be described further below. Shortly thereafter, a positive pulse arrives at tube 1081 via conductor 1,

which is turned over and appears as a negative impulse on the grid of the right system of the tube io6i. The load circuit of the tube 1081 now contains the inductance 1091. This inductance ensures that the negative pulse generated at the anode 1081 is immediately followed by a positive pulse, so that the pulse arriving at the grid of the right system of 1061 is a negative-positive pulse . This pulse is in turn converted by the right system of the tube 1061 into a positive-negative pulse, which is transmitted via the transformer 1071 to the control circuit of the conductance G _1. The shape of this negative-positive pulse and the time of its occurrence is shown on line 1 in FIG. A similar circuit is connected to each of the conductors 2, 3 ... η connected to Göben a relatively large negative pulse to the corresponding Leitwertsteuerkreis the time of the M pulse, the reference value is set to the condition of a lowest value, and also to to transmit a positive-negative pulse to the control devices of the corresponding conductance values at a later point in time, in the manner and at the time as indicated by the lines 2 to η in Füg. 4 is shown.

In the tube circles described so far are

various electrical switching elements are used.

The resistors r _v r ₂ and r ₃ are parallel to the primary windings of the transformers 1071, 1072, 1073 etc. Such resistors are also used in the primary windings of other transformers in this facility. They serve to steepen the impulses transmitted by the transformers and have a corresponding value. Furthermore, they serve to suppress the differentiation effect, so that the generation of an additional reverse pulse is prevented. All other switching elements have a purpose known to those skilled in the art and do not need to be described further.

Modulator I.

The modulator circuit I shown in Fig. 8 will now be described. A non-sinusoidal oscillation, which consists of numerous frequencies, the highest of which is assumed to be 4000 Hz in the present case, arrives at the primary winding of the transformer 810. At time t _m , a positive pulse arrives at the grid of the tube 1020 (FIG. 10), is converted by the transformer 1019 and reaches the anodes and cathodes of the diodes 811 and 812 (FIG. 8) as a negative-positive pulse. The negative pulse creates a current in the tube 812, which discharges the capacitor 814. When the positive pulse reaches the diodes immediately afterwards, a current is created in the tube 811, which charges the capacitor to a certain potential. This potential is equal to the positive pulse, increased by the amplitude of the oscillation at the time the instantaneous amplitude was determined and decreased by a constant bias voltage determined by the battery 816. The grid of tube 8201 remains at this potential, reduced by a bias voltage from battery 821, until another pulse arrives at time t _{m + 1.} The output voltage of the amplifier tube 820 appears at the resistor 825 and controls a conventional push-pull modulator of some kind. In the example shown here, this contains two varistors V ₁ and V ₂ . In addition, an oscillator II is connected to the push-pull _{modulator, the frequency / 0 of which is} high compared to the frequencies occurring in the non-sinusoidal oscillation. In a known manner, a carrier frequency f ₀ appears on the secondary winding of the transformer 830 , the amplitude of which is proportional to the voltage across the resistor 825. The phase of the voltage on the secondary winding of 830 reverses when the voltage on resistor 825 changes direction. The secondary winding of 830 is connected to the grid circuit of the pentode 835, which in turn supplies the output current I _m. This current is almost independent of the load, which consists of a resistor or a parallel resonant circuit 837 and the associated switching elements, which will be described below.

Oscillator II

Any suitable oscillator of a known type which supplies an essentially sinusoidal output voltage of sufficiently constant frequency can be used as oscillator II. The load circuit of the pentode 835 contains several conductance elements G ₁ , G _2. ·· G _n connected in parallel, as shown in FIG. 9, which are controlled as described further below. The total current flowing through these conductance values connected in parallel, regardless of the value of the conductance values, is. given by I _m ; because the value of the current of the pentode 835 is, as stated above, essentially independent of the value of the conductance values.

Homodyne detector IV

As part of the load circuit of the pentode 835, the homodyne detector IV (see Fig. 9) is also connected, the purpose of which is to. To demodulate current I _m with the frequency / ₀ after the change by the attenuators. The homodyne detector includes a tube, shown as triode 901. It serves as an amplifier. However, it has more the task of not adding any significant conductance to the load circuit of the 835 pentode. At the output of the tube 901, a demodulator circuit 904 with two generally varistors V ₃ and V _{1 is} connected via the transformer 902 and receives oscillations from the oscillator II. At the output of the demodulator, a voltage appears at resistor 907 of a magnitude that depends on the amplitude of I _m after change due to the inserted conductance values. As long as the high-frequency

Current I _{m has} a phase as in the. three sections 303, 303 ^ and 3033 on the third line in Figure 3, one terminal of resistor 907, say the right terminal, will be positive. Let us denote this case with a positive outcome. If, however, the amplitude of the non-sinusoidal oscillation assumes a negative value, as shown by the instantaneous amplitude determined at time t _{m + 3} on line 1, corresponding to 3O2 ₃ on line 2 and 3O3 _g on line 3 in FIG Secondary winding of 830 appearing high frequency the opposite phase, where its amplitude is still proportional to the instantaneous amplitude and its frequency is f ₀ . The polarity at resistor 907 is thus also reversed. The homodyne detector delivers a message which is later used to determine both the polarity and the instantaneous amplitude of the oscillation.

Polarity and amplitude detector V

The polarity and amplitude detector V is shown in the lower part of FIG. if the output voltage of the homodyne detector at resistors 907 and 908 is greater than an arbitrary one The reference value is the. can be regulated by the bias source 921, so a current flows in one of the tubes 924 and 925.

When this output voltage has such a direction that the potential of the grid of 924 increases becomes, and if its amplitude is large enough, then the grid of the tube 926 becomes strong negative. Hence, one coming from the tube 1021 becomes P-pulse, which reaches the grid circle of the tube 926 via the transformer 927, do not cause a pulse in the tube 926 and in the line which leads from there to the transmitter VII. If the output voltage of the homodyne detector has the opposite 'polarity, the grid of tube 926 will be only slightly negative, and that coming through transformer 927 Pulse will cause a current in the anode circuit of tube 926, causing a pulse across the transformer 928 is transmitted to the transmitter.

If the output voltage of the homodyne detector is greater than an arbitrary value in one direction, a current flows in the diode 929 because of the voltage drop across the resistor 922, whereby a positive bias voltage is applied to the conductance controls and prevents the pulse generator VI from being sent to a particular one Control circuit C ₁₁ C ₂ ... C _n incoming pulse removes the corresponding conductance G ₁ , G ₂ ... G _n.

Conductivity III

In FIG. 9, several conductance values and conductance control circuits are drawn, one for each pulse in the amplitude code. Three such units G ₁ C ₁ , G ₂ C ₂ and G _n C _n are shown. Since their mode of operation is the same regardless of the timing of their work, only one of them needs to be described. The one labeled III is chosen which contains the first conductance G ₁ and the control circuit C ₁ .

The conductance _{circuit G 1} essentially consists of a feedback amplifier connected in parallel. It contains the series-connected resistors R ₁ and R ₁ , the common point of which is connected to the three-stage amplifier with the tubes 941, 942 and 943 and with resistance-capacitance coupling. A feedback leads from the anode of the last tube 943 via the capacitor 944 to the grid of 941. Of course, another form of coupling, e.g. B. current resonance coupling can be selected. Either no amplification or a very large amplification occurs, depending on whether the control voltage applied to terminals α and b blocks one or more of the tubes or allows them to operate. In the illustrated amplifier, the circuit is opened by a sufficiently large negative bias on the grid of the tube 942. But when the circle is open, the conductance is essential

. If a big enough positive

U ₁ -f- U

Impulse arrives at point b , the circle is closed. When the gain in the circle is high, R ₁ appears to be short-circuited so that the conductance G _{1 is} essentially 1IR ₁ , almost independently of the gain. In this way, a high level of control accuracy for the conductance G _{1 can be achieved} independently of the tube characteristics. Although the control has been shown for only one tube for the purposes of illustration, it may be desirable to control the bias of some or all of the tubes of the feedback amplifier to fully open the circuit.

The control circuit C _{1 of} the conductance circuit G ₁ consists of several diodes 951, 952 and 953 and the associated switching elements. When a positive pulse arrives from tubes 1061 and 1081 in FIG. 10, diode 951 becomes conductive, charging capacitor 954, applying a positive potential to b and closing the feedback circuit. This increases the conductance G ₁ to such a value that only 1 / R _{1 is switched} into the load circuit. Immediately thereafter, a negative pulse arrives at the diode 952 via the transformer 955. If this is the only pulse at the diode 952, ie if the positive bias voltage coming from the amplitude and polarity detector V is too low because the output voltage of the homodyne detector IV is below one is a certain reference value, the negative pulse discharges the (capacitor 954 and opens the feedback circuit. This _{removes the conductance G 1} , ie the conductance introduced into the load circuit _{by G 1 becomes}

to its lowest possible value ——: - = - 7- ge

Ii ₁ -J- Ji ₁

brings. At the same time, a current flows in resistor 958 and tube 953, towards the transmitter a negative pulse goes, causing a yes signal to be transmitted. If from the polarity

and amplitude detector V a positive bias voltage of sufficient magnitude is supplied via diode 929, which means a large output voltage at the homodyne detector, the negative pulse coming via transformer 955 is insufficient to cause a current to flow in diode 952. As a result, the conductance G ₁ remains switched on and no pulse is transmitted to the transmitter, which results in a no signal.

If the conductance G ₁ remains switched on, the signal arriving at the tube 901 is correspondingly attenuated. When the next pulse arrives, corresponding to channel 2, the instantaneous amplitude is again checked _{by inserting the conductance value G 2.} G ₂ is removed or not removed depending on the magnitude of the instantaneous amplitude, ie the amplitude of the voltage applied to the input or grid of the tube 901. This will become clearer upon consideration of FIG. For the sake of simplicity, it is assumed here that, apart from the polarity pulse, a five-digit permutation code of a binary system is used. This code makes it possible to distinguish between 32 different amplitudes, the change caused by the first conductance G ₁ being approximately as large as the change caused by the fifth conductance. The change caused by the second conductance is 8 times, due to the third 4 times, and 2 times as large as the fourth, ie the range from G ₀ to 31 G ₀ has steps of G ₀ . The reference level V ₀ is a voltage unit (assume 1 mV). If, upon insertion of a conductance, the amplitude reaching the tube 901 is greater than this value, the conductance remains; if it is * less, it will be removed. The lowest possible conductance value G _{n of} the circle is very small compared to the smallest conductance value level G ₀ , as stated above.

If one further assumes that the instantaneous amplitude of the oscillation is somewhat larger than 22 units, ie smaller than 22.5 units (see the scale shown on the left in FIG. 5 with 32 units), then the insertion of the conductance G ₁ by the positive pulse in channel 1 so that the voltage coming to tube 901 around the

Is reduced by a factor of 16, i.e. H. on

22 + 16

Units.

The residual voltage is therefore greater than the reference level V ₀ (ι unit) as shown by α in FIG. The immediately following negative pulse _{does not remove G 1} because the system now knows that the instantaneous amplitude was greater than 16 units. If the amplitude had been less than 16 units, the residual voltage would have been less than V ₀ and the conductance G ₁ would have been removed. The positive pulse in channel 2 now inserts the second conductance G ₂ with the value 8, so that a total conductance of 24 units is switched on. The residual voltage is now ——

this is less than V ₀ as shown by b in FIG. Therefore, the negative pulse immediately following in channel 2 removes G ₂ . The positive pulse in channel 3 now inserts G ₃ with conductance 4, so that a total of 20 units are switched on. The residual voltage is on ? ^ - L

decreased as shown by c . That is more than V ₀ . Therefore G ₃ remains switched on. In the same way, the positive pulse in channel 4 inserts G ₄ with conductance 2, so that overall conductance 22

will. The residual voltage is

22 +

Units, so

slightly more than V ₀ , so G ₄ stays on. Now the positive pulse inserts G ₃ with the value 1 in channel 5, so that the overall conductance 23 and

the residual stress

Units is, so something

more than V ₀ , represented by e. Whether G _{5 is} left on or removed depends on whether the 22+ units value for the instantaneous amplitude is closer to 22 or 23 units. The boundary conditions of the conductance control circuits are set so that if the instantaneous _{amplitude is exactly 22.5 (units large, the negative pulse to control G 5} is insufficient _{to remove G 5.} If the amplitude is less than 22.5 units, as assumed in this example, the negative pulse removes G _3. So the total conductance switched on in front of the input of the tube 901 is 16 + 0 + 4 + 2 - 0 = 22 and the corresponding code is No - Yes - No - No - Yes (0 - 00 -) arises and is sent. The voltage drop at the conductance values G ₁ , G ₂ ... G ₅ is therefore set as close as possible to the reference level V _0. If the total value is denoted by G ^

becomes, V ₀ = - = -pr-.

^u G ₁ + G ₂ + ... G _n Gt

Since the conductance G _{t is given} by the binary number, which is represented by the η no and yes signals, this number expresses the amplitude of the current I _m and thus the amplitude of the non-sinusoidal oscillation at the time when the amplitude was determined.

Using a six-digit code, the system can distinguish between 64 different amplitude values. If you expand the code to a higher number of digits, any degree of fineness can be achieved with a correspondingly increased fidelity the vibration can be achieved. From the above description it is clear that in each case the entire Activated conductance within half a reference level unit of the instantaneous amplitude is proportional to the vibration.

There is a small error in the above calculation, which lies in the fact that the smallest possible conductance is not zero, although it is _{very small compared to the conductance G 0 of} the small steps. However, the same condition also exists in the opposite sense in the receiving station, so that the error is practically eliminated. It is important that a certain conductance combination is set in the transmitting station and that means are provided to set exactly the same or proportional conductance values in the receiving station.

During the setting of the conductance values, pulses are modulated onto a suitable carrier transmitted by the transmitter VII, which bring the message to the receiving station, which guide values have been switched on. The amplitude of each pulse transmitted by the transmitter is the same. Each The signal element transmitting the message consists only of No or Yes. As a result, a such signal can be amplified indefinitely without

ίο that there is a distortion or disturbance of the message arises even if the amplifier has distortion or interference to a certain extent Have dimensions. Hence the requirements are made on the amplifier itself for transmissions using high transmission quality is very low. A long-distance transmission with many amplifiers is possible. The presence and occurrence of interference on the transmission path from the transmitter VII to the receiving station

ao has no effect as long as the interference level is relatively small compared to the amplitude of the transmitted signal pulses. The disturbances will therefore not appear in the signal if it is reproduced.

It should be noted that this type of construction of the Conductive values to determine the instantaneous amplitudes, essentially an additive method represents, starting with large levels and moving on to smaller and smaller levels until the

ao the final degree of intended delicacy has been reached. Viewed from another point of view, the method is subtractive in that, by inserting each conductance, the voltage generated in the tube 835 is reduced by subtraction until a value close to the reference level V _{0 is} reached. This additive or subtractive property is a special feature of this system and forms a distinguishing feature of the present invention.

Sender VII

During operation, a sequence of pulses arrives at the transformer 850 of the transmitter VII (FIG. 8) via the channel T , one for each pulse of the pulse generator VI; the time of arrival is as shown on the lower line in FIG. These pulses act on the grid of tube 855.

In addition, certain pulses arrive at the transformer 852, one for each every yes impulse. They either refer to the polarity or they indicate that one of the conductance values inserted and removed again. No pulse reaches transformer 852 if a Conductance was inserted into the load circuit, but not removed again, resulting in a no signal is equivalent to. The secondary coil of transformer 852 operates on a second grid of the

Tube 855. The tile tube, in turn, controls transmission or non-transmission over an appropriate medium to a remote receiving station. In FIG. 8, the tube 855 is shown as a control and transmission element 860 for a high-frequency channel on a suitable carrier, but the pulses coming from the tube 855 can of course be given directly to a suitable transmission path, e.g. B. on two parallel wires, a coaxial cable, etc. In this case it is not necessary and may also be undesirable to modulate the pulses onto a carrier. The transformers 850 and 852 are connected to one another in such a way that a pulse arriving at 850 alone does not cause a signal to be transmitted, that a signal is only transmitted to 850 and 852 if a pulse is present at the same time, which corresponds to a yes signal. This does not apply to the first broad pulse of the T-sequence, which for this purpose has a greater amplitude than the other pulses - so that it can put the tube 855 into operation without outside help. However, all pulses are preferably brought to the same level prior to actual transmission. The purpose of the impulses arriving via the T-channel is to ensure that the signal impulses are transmitted correctly at times. In some cases, this additional precaution is not required. Then the Γ-i channel including the tubes 1024-1029 in Fig. 10 and the transformer 850 can be omitted. In this case, the transformer 852 and tube 855 are sized so that one pulse at 852 is sufficient to effect the transmission.

recipient

The problem of restoring the modulation oscillation in the receiving station is something easier. It will first be described with the aid of the block diagram in FIG. at In the present example, pulses that represent the signal appear for all yes signals. A Pulse generator VIII is synchronized with the incoming pulse, e.g. B. by a marker or Synchronization pulse, such as the M pulse of the Transmitting station so that it works properly in sync with the incoming signals. The pulse generator VIII sends impulses to various devices that also receive the signal. The signal alone, like the impulses alone, does not cause the facilities to become inactive. On the other hand, a signal pulse together with a pulse from VIII sets the various devices in action.

At the time when the signal corresponding to the P pulse appears, the pulse generator VIII sends a pulse to the phase shifter IX. If it is a no signal or no signal, the phase shifter is influenced in such a way that it carries ^{out a phase shift of i8o a.} If it is a yes signal, the phase shifter is manipulated to shift the phase by zero degrees. The phase shifter consecrates in this state until it receives a new P-Im-

pulse gets. The next pulse of the pulse generator VIII goes to the electrically controlled conductance G ₁ . The pulse controls the change in the conductance proportional to G ₁ in FIGS. 1 and 9. The conductance initially has its minimum value. If the recorded signal is a no signal, the conductance G _{1 is} switched on. If a yes signal is received, this process is prevented and the conductance remains in the state of the lowest conductance. The next pulse from the pulse generator VIII goes to the conductance G ₂ at the same time as the signal from the conductance G ₂ in Fig. 1 arrives, and so on, up to the conductance G _n . In this way the overall conductance becomes proportional to that in the transmitting station in Fig. 1 which is causing the no and yes signals. After a short time, preferably with the next marking pulse at the time when the next instantaneous amplitude of the non-sinusoidal oscillation is determined in the transmitting station, a pulse from the pulse generator VIII sets the oscillator X into action. This acts as a constant voltage source having a desired frequency, which provides the conductance XIII a voltage and a current through the _n conductances G _1, G ₂ ... G and sends the resistor R. R lies parallel to the line from the conductance values XIII to the homodyne detector XI. R is small against

The voltage drop across R generates an output pulse at the homodyne detector XI which is almost proportional to the amplitude of the oscillation at the time when the amplitude is determined in the transmitting station. After the pulse that goes to the oscillator X, a reset pulse follows. This puts the conductance values G ₁ G ₂ ... G _n in the receiving station and the phase shifter IX back into the initial state in preparation for the next amplitude code. The pulses from the detector XI go through a low-pass filter XII. When the highest occurring in the vibration

Frequency f _m = - = rist and if the low-pass filter

has a cut-off frequency f _m , a signal is obtained at the output of the low-pass filter which is proportional to the amplitude, but which is preferably delayed by T seconds, where T is the time between the successive instantaneous amplitudes of the non-sinusoidal oscillation in the transmitting station.

After briefly describing the block diagram in FIG. 2, a more detailed description will now be given An in-depth explanation of the facilities that perform the operations described above will be given carry out. It will be apparent to those skilled in the art that there are numerous

fin circuit arrangements for this. In the Figures 11, 12 and 13 are certain specific arrangements which are only intended to serve as specific examples. Of course are many modifications are possible without departing from the spirit of the invention.

In FIG. 11, a receiving device 1106 is shown in particular, which is specified as a wireless receiver with a suitable receiving antenna 1105. The device 1106 is a wireless receiver with rectifier of any suitable type which provides 7 "signal pulses which reproduce the pulses coming from the transmitter VII in FIG The output voltage of the tube 1109 goes to a plurality of control devices C ₁ ... C _n , which are connected to a plurality of conductance values G ₁ ... G _n in the manner described below.

Receiver pulse generator VIII

A voltage is tapped off at the output of the tube 1108, which is generated by suitable amplifiers goes (1112 and 1114). The one at the output of the amplifier The pulse which appears is used to control the relaxation generator shown in FIG. This Tilt generator, which is grouped around the gas discharge tube 1310, can be the same in all respects Tilt generator 1010 be in the transmitting station, the is shown in Fig. 10 in detail. The switching elements 1010 to 1015 in FIG. 10 correspond in Fig. 13 the switching elements 1310 to 1315. The determinative values of the relaxation generator in Fig. 13, however, are dimensioned so that the circuit does not normally oscillate, but does triggered by a pulse coming from tube 1114. In addition, the determination values are dimensioned so that the circuit at the first pulse of each group (according to the .M-impulse in the transmitting station) flips; afterwards can they no longer flip until the next JW pulse arrives.

This is done by using the long initial T-pulse, as shown in Fig. 4, which has already been mentioned became. It should be recalled that all transmitted by transmitter VII Pulses have the same amplitude. However, since the tube 1112 is a device with constant Is current, the voltage built up across the parallel resonance circuit 1113 is proportional to the duration of the incoming pulses. In this way, those arriving at 1310 have the M pulses corresponding to them Pulses larger, preferably twice the amplitude, so that they can trigger the oscillating generator 1310 for Can cause tipping, while the other impulses of the period cannot.

In a manner analogous to that in FIG. 10, a delay circuit 1316 is connected to the tilt generator connected, can be tapped from the sequences of pulses with time intervals that are almost are identical to the time intervals at which the pulses from the delay circuit 1016 in FIG the transmitting station. be tapped. The delay circuit 1316 has an additional element, which supplies an impulse denoted by '', whichever only a little delayed compared to the previous one

M-pulse is. The function of the µ 'pulse will be explained later. The delay circuit 1316 is terminated by a suitable impedance 1318 to avoid reflections. There are also a number of tubes 1325-1329 which act as cathode amplifiers and emit sequences of positive pulses which correspond to the pulses supplied by the delay circuit 1316.
10

Receiver conductance XIIl

The use of the various pulses for controlling the setting of the conductance values G ₁ ... G _n in accordance with the setting of the conductance values in the transmitting station will now be described. The conductance values in Figure 12 may be identical to those in the transmitting station or they may be proportional to them. Three circles are drawn: Conductance G ₁ with its control circuit C ₁ ; G ₂ with C ₂ and G _n with C _n . Apart from the point in time at which the pulses occur, their mode of operation is the same, so only the first conductance value G ₁ with its control circuit C _{1 is} described. The conductance circuit G ₁ is essentially a parallel feedback amplifier, • which contains the resistors R ₁ and R _{1 connected in series} . The connection point of the resistors is connected to the three stage amplifier which includes tubes 1241, 1242 and 1243 with resistance-capacitance coupling or some other suitable coupling. A feedback connection is provided from the anode of the last tube 1243 through capacitor 1244 to the grid of tube 1241. In the amplifier circuit there is a gain of "zero or a large gain, depending on whether the control voltage applied to terminals α and b blocks one or more tubes or leaves them in operation. In the amplifier shown here, as in the amplifier in FIG 9, the "circuit is normally open by a sufficiently negative bias on the grid of tube 1242. Under this condition the conductance is substantial

- -ry. If a positive impulse from

• Kj + ^R i

of sufficient size arrives at b , the circle is closed. When the gain in the circle is high, the conductance G ₁ becomes essentially 1 / R ₁ , almost independently of the gain. The corresponding master value is inserted into the load circuit. Even if the control is only shown here on one tube for the sake of explanation, the pretensioning of several or all of the tubes can, if desired, be controlled in order to achieve a complete opening of the circuit.

The control circuit C _{1 of} the conductance G ₁ can assume many different circuit forms if it only performs the desired functions with the pulses that reach it. It may include one or more diodes or combinations of diodes and triodes or multigrid tubes in various ways, as will be apparent to those skilled in the art. In FIG. 12, it is specifically shown as a combination of a diode 1251 and a triode 1257. A positive pulse of the delay circuit 1316 corresponding to the M pulse goes to the transformer 1252, which is polarized such that the cathode of the diode 1251 becomes negative. Any positive charge on capacitor 1254 is discharged so that the negative bias on tube 1242 opens the conductance circuit. This happens simultaneously for all conductance circuits at the beginning of a cycle 1 of the delay circuit 1316 and a pulse coming from the tube 1327 at the transformer 1256, which is polarized in such a way that the grid of the tube 1257 becomes positive. A current then flows through the anode circuit and gives the upper layer of the capacitor 1254 a positive charge, It is assumed that only the impulse coming from the transformer 1256 acts on the tube 1257. This is the case with a no signal reaching the receiving station. then the signal goes through transformer 1258 to the anode of tube 1257 so that the effect of the positive pulse is am Lattice of tube 1257 is lifted. Now there is no anode current flowing. As a result, capacitor 1254 does not receive a charge and the conductance circuit remains open. Recall that a no signal in the permutation code indicates that a conductance is being switched on in the transmitting station. So you can see that the conductance G ₁ . is inserted in the receiving station if the corresponding guide value G _{1 has been} inserted in the sending station, and that it is not inserted if it has also not been inserted in the sending station. Just as well as the conductance G ₁ ... G _n operate in the receiving station, so that the combination of turned-on at the receiving station guide values will be the same as that in the transmitting station.

Oscillator X

An oscillator X, which is shown in FIG. 11 as 1120, is provided in the receiving station. This can have the same frequency as the oscillator II in the transmitting station, but it needs it not. In other words: no synchronism between the two oscillators is necessary.

Phase shifter IX

The phase shifter includes, as shown in FIG is, two triodes 1221 and 1222, whose Lattice circles across the transformer 1223 'parallel be supplied by the oscillator 1120. In the starting circle is the transformer 1224, whose primary winding with its center on the

Battery 1237 is located. The grid circle of the tube 1221 contains the capacitor 1225. In the grid circle of the tube 1222 is the battery 1226, which the grid should give a positive bias. In the normal case, the steepness of the tube 1222 is therefore greater than that of the tube 1221. In the secondary winding of the transformer 1224 there is an alternating current of the frequency of the oscillator and with a certain phase. The phase of the current however, the phase shifter can be used to reverse the secondary winding. The phase shifter consists of the diodes 1231 and 1232, the are usually biased so that they do not conduct. When a pulse corresponding to the P pulse from the tube 1326 arrives at the transformer 1233, it is polarized so that the diode 1231 becomes conductive. The capacitor 1225 receives a negative charge of such magnitude that the tube

1221 has a higher steepness than tube 1222, whereupon the phase of the current flowing in the secondary winding of transformer 1224 is reversed will. This reversal takes place if a no signal was given in the transmitting station, d. H. if no pulse was received. The capacitor 1225 is connected so that it his Retains charge for a full cycle.

If the polarity of the instantaneous amplitude of the non-sinusoidal oscillation in the transmitter is negative a yes impulse is transmitted and received in the receiving station. Hence arrives at that Transformer 1234 and thus to transformers 1258, 1278 ... 1298 on the master value control circuits a corresponding pulse, the transformer 1234 is polarized so that this pulse counteracts the impulse coming from the transformer 1233. As a result, the diode becomes 1231 non-conductive, the capacitor 1225 is not charged and the phase of the oscillations in the Transformer 1224 secondary winding is not reversed. At the end of the cycle respectively to The beginning of the next cycle makes the pulse from the tube 1325 via the transformer 1236 the Diode 1232 conductive, whereupon the capacitor 1225 is discharged or reset to the normal state will. With the help of the means described, it is possible, as you can see, the phase to shift the oscillation currents in the transformer 1224 by i8o °.

The output of transformer 1224 is parallel to resistor 1216, which corresponds to resistor R in FIG. _{The combination of the conductance values G 1} ... G _n is also in series with the resistor 1216 , the resistance 1216 being small compared to the resistance of the parallel conductance values. Furthermore, the tubes 1221 and

1222 appear by suitable means as a low resistance voltage source, be it that they are tubes with low resistance, or by using cathode amplifiers or a step-down transformer. In this way both the amplitude of the current is in the resistor 1216 and with it the voltage fluctuation at its terminals as well as the current in the transformer 1214 proportional to the conductance values specified in of the receiving station, and therefore also the instantaneous amplitude of the non-sinusoidal Vibration in the transmitter.

Homodyne detector XI

The homodyne detector XI contains a push-pull demodulator with varistors 1211 and 1212, which are arranged in a normal bridge circuit. This demodulator receives over the transformer 1213 directly the oscillator frequency of the oscillator 1120 and also the same Frequency through transformer 1214. The primary winding of the transformer 1214 is in the anode circuit of the triode 1215, whose grid circle is the Includes resistor 1216. In this way, those appearing on resistor 1217 are rectified Pulse frequency currents proportional to the current in transformer 1214 and therefore in all respects proportional to the current and the voltage of the oscillation amplitude in the transmitter. If the The polarity of the current of the oscillation is reversed in the transmitter, the voltage on turns Resistance 1217 also around.

Finally, the task of the multi-grid tube 1218 should be explained. This tube is normally biased so that it is blocked. However, via the additional element of the delay circuit 1316, an above-mentioned positive pulse n 'reaches the triodes 1351 and 1352 connected in series, which result in an amplification without changing the polarity. Very shortly after the completion of the amplitude code, a positive pulse of such a height is applied to a grid of the tube 1218 that the tube 1218 becomes operational for the duration of the pulse ri. During this period, a pulse appears in the output circuit of 1218 which is determined by the magnitude and direction of the voltage across resistor 1216, which in turn is proportional to the amplitude and polarity of the non-sinusoidal oscillation. These impulses follow one another, always one impulse per momentary amplitude. With the help of the low-pass filter 1219, the undesired high frequencies can be eliminated, no The resulting oscillation is a true-to-life image of the original non-sinusoidal oscillation in the transmitting station after passing through the terminal device and the receiver.

In this explanation, the invention has been described on the basis of special devices. This is over For the sake of clarity, obviously many significant changes can be made in the System without departing from the spirit of the invention. For example, the 12 shows a special arrangement for controlling the conductance values which the diode 1251 and the Includes triode 1257. Another embodiment is shown in FIG. 14, where the triode 1257 is replaced by a second diode 1253 is replaced. The reset pulse,

arriving via transformer 1252 discharges capacitor 1254 as above. A pulse arriving from the pulse generator via the transformer 1256 is polarized in such a way that the diode 1253 becomes conductive if only this pulse is received. The capacitor 1254 can then be charged and a conductance value inserted, which corresponds to a no signal. If a yes signal arrives, it goes via the transformer 1258 to the diode 1253. The transformer 1258 is polarized in such a way that the pulse counteracts the pulse coming from the transformer 1256 at the same time. As a result, the diode 1253 will become nonconductive, the capacitor 1254 will not receive a charge, and the corresponding conductance will be. not inserted. Many other modifications can also be made, e.g. B. the T-pulse channel can be omitted with appropriate simplifications, but also with some damage to the control. In addition, the oscillator in the receiving station can work continuously instead of only being triggered occasionally; for even then it is inactive at the output of the system until the tube 1218 is made operational by the pulse coming from n '. Furthermore, one can obviously omit the modulation and demodulation in the transmitting station, with the amplitude signals from the tube 820 going directly to the input of the tube 835, and directly from the tube 901 to the resistor 907 or to its counterpart, without the interposition of the demodulator in the homodyne detector IV. This also means the omission of the oscillator II. Corresponding changes can be made in the receiving station at the oscillator. In general, however, such omissions and simplifications are carried out to the detriment of the operation and the quality. How far to go with such simplifications is a matter of technical consideration.

The radio frequency or carrier frequency on which the signals are transmitted has not been specifically mentioned. Of course, you can use any suitable value for the radio frequency or carrier frequency, as long as it is high enough that the bandwidth required for the system can be transmitted. For example, this carrier can be in the so-called microwave range, yes this is even excellent and particularly suitable for it, regardless of whether direct transmission or transmission via coaxial cables, waveguides or similar transmission paths is selected.
55

Claims (12)

PATENT CLAIMS: i. Electrical transmission system for non-sinusoidal vibrations, in which the instantaneous amplitudes determined in short time intervals by code groups of pulses are transmitted, with all code groups having the same number of pulses contain, each pulse either a fixed, non-zero magnitude or the Size zero · has, and the various code groups have the instantaneous amplitude values, in Steps divided, represent, the step value stored as a potential of a capacitor connected to the input of an amplification modulator, thereby characterized in that a plurality of conductance values, one for each pulse position the code groups are intended to be provided in such an arrangement that they are under the '75 joint control of the stored potential and one from a pulse generator given Impulszykhis in parallel and in time sequence to the output of the amplifier modulator be connected so that its effective output voltage is reduced to a value above an arbitrary reference value, and that it is from the Parallel connection can be removed - as soon as the effective output voltage is obtained when connected is reduced below the "reference value, so that the sum of the by those in the parallel connection the remaining conductance is reduced, the effective output voltage is reduced essentially to the reference value, and that means are provided which the pulse train of the via the stepwise connection and maintaining the connection or via connection and disconnection of the successive Code groups that provide information are transmitted to a receiving station. 2. Transmission system according to claim 1, characterized in that the successive, Reductions in the effective output voltage caused by the conductance are of such a magnitude that they are multiples represents the reduction caused by the last conductance. 3. Transmission system according to claim 1 t ° 5 or 2, characterized in that each conductance contains a control circuit and the pulse generator is set up so that the pulse cycles emanating from it have an initial pulse which defines the time for the determination "° the momentary amplitude of the vibration to be transmitted, a further impulse, which serves as a polarity impulse when checking the polarity of the specific instantaneous amplitude and contains remaining impulses, which in turn come into effect through the control circuits of the master values and in the Combined with the effective ones existing in the modulator output at the time of the impulse Residual voltages successively connect those conductance values to the output sustained until the end of a pulse cycle, which is the effective voltage on the arbitrary reference value. 4: Transmission system according to claim 3, characterized in that the one with its input output connected to the storage capacitor modulator is set up so that it supplies a current proportional to the storage tank charge that lasts for the duration of the period of time between successive determinations of the instantaneous amplitude constant and im is essentially independent of the load that a polarity and amplitude display circuit connected to the voltage at the ίο takes up load and the same or their The residual value is applied to the control circuits of the individual master values one after the other, and at the same time with the application of the special pulse supplied by the pulse generator the control circuits, and that from each of the control circuits a circuit to the transmission means leads to transmit a pulse of predetermined, non-zero size to the 'receiving station, if the relevant conductance is removed, on the other hand a pulse of size zero, if the relevant conductance remains connected. 5. Transmission system according to one of claims 3 and 4, characterized in that each conductance represents a resistance in the input of a shunt feedback amplifier contains, which controls the size of this resistance and in turn by the assigned control circuit is controlled. 6. Transmission system according to claim 1, characterized in that the modulator is controlled by the capacitor charge and a receiver oscillator whose Frequency is above that of the successive determinations of the instantaneous amplitude, and that of its impulses with one proportional to the capacitor charge and for the time between successive ones Determinations of the instantaneous amplitude gives constant amplitude that a circuit for transmitting the voltage applied to the load to a demodulator circuit and a polarity and amplitude detector is provided, normally switched-off conductance values can be switched in parallel to the load in order to reduce the Demodulator to reduce the voltage occurring, and each conductance a special one Control circuit is assigned, wherein the pulse generator is arranged so that it pulse cycles generated, the number of evenly distributed impulses increased by two Number of conductive circles whose first pulse is the time for determining the Measures the instantaneous amplitude of the vibration to be transmitted, and its second impulse serves as a polarity pulse to determine the duration of the detector operation when testing the Set the polarity of the capacitor charge during the remaining pulses of a cycle one after the other via the individual control circuits of the master values for the purpose of interaction with the amplitude of the determination value or its residual size can be applied to the To introduce each conductance one after the other parallel to the load and to maintain this connection, if the residual amplitude now occurring at the amplitude detector is above of the reference level, or cancel if the residual amplitude is below the reference level, and that each control circuit and the transmission means assigned circle is provided to the receiving station a Pulse of size zero to be transmitted if the relevant conductance is shunted remains switched on, on the other hand a pulse of a predetermined size deviating from zero, when the conductance shunt is broken, the conductance from the largest to the smallest reduction in size caused by them are the reduction that occurs at each stage on the detector, the connected one Conductance is proportional, and the sum of the reductions is proportional to the particular instantaneous amplitude. 7. Transmission system according to claim 1, characterized by being equipped with a pulse generator for the delivery of Pulse cycles consisting of a marking pulse, a polarity pulse and a series there are additional positive pulses, the number of which is equal to the number of conductance values, where every additional positive pulse is immediately followed by a negative pulse, a push-pull modulator to which the marker pulse is applied simultaneously with the to transmitted oscillation is applied to a first potential on the storage capacitor cause a source of superimposed vibrations compared to the one high frequency at the time between successive amplitude determinations have and are applied to the push-pull modulator to a proportional to the first potential and to supply current maintained for the period between successive amplitude determinations, which is applied in turn to each of the parallel conductive circuits, a control circuit for each of the conductance values, which each of the positive and negative additional impulses from the pulse generator is accordingly fed to a homodyne detector which is connected to a polarity and amplitude detector at the end of the conductance values is connected is to a second potential from the current changed by ■ the corresponding conductance to generate, wherein the polarity and amplitude detector the second potential to the relevant Control circuit leads, the positive pulse leads each control circuit according to the sequence actuated to connect the associated conductance for the purpose of changing the current, the following negative impulse den Control circuit operated to disconnect the connected conductance only when the second potential applied to it exceeds the reference level, and each control circuit is set up in this way is that it generates an impulse of a predetermined non-zero size only lets through the transmission means if the relevant conductance is disconnected if necessary is. ίο 8. Transmission system according to claim 7, characterized characterized in that the pulse generator includes an electron discharge device, which has a capacitor and a cathode resistor in parallel to the output Such an arrangement has, - that the capacitor is through the electron discharge device with a speed which is decisive for the period between successive determinations of the instantaneous amplitude discharges to produce a sharp pulse at the cathode resistor, and that in parallel with the cathode resistor there is a delay line along which the sharp pulse travels with the marker pulse directly from the cathode resistor removed the polarity pulse from the first section of the delay line and the additional positive pulses from the subsequent sections of the delay line and the delay line is arranged so that the sharp pulse runs the entire length of the line before the next discharge of the output capacitor takes place. 9- transmission system according to claim 8, characterized characterized in that a series of • electron discharge devices, each of which cooperates with a transformer, actuated by the positive additional pulses to generate the immediately following negative pulses. 10. Transmission system according to one of claims 7 to 9, characterized in that each conductance contains a resistor in the input of a shunt feedback amplifier, which is the size of the input resistance effectively connected in parallel to the push-pull modulator controls that the feedback amplifier is in turn controlled by the associated control circuit, and that each Control circuit: a plurality of two-pole tubes and a capacitor in such an arrangement contains that a positive pulse arriving at the control circuit removes the control circuit capacitor charges to a certain amount, the control circuit capacitor with the feedback amplifier is coupled, after its charging to the certain value, the feedback circuit . of the feedback amplifier closes and shunts the reduced value of its input resistance of the push-pull modulator output. introduces, while the immediately following negative When the pulse arrives at the control circuit, it only discharges the control circuit capacitor if the one applied to the control circuit Determination amplitude is below the reference level to open the feedback circuit and the input resistance of the feedback amplifier from the shunt connection to remove the push-pull modulator output. 11. Transmission system according to one of the preceding Claims, characterized in that the receiver with a pulse generator is equipped, which is triggered by the first pulse in the cycle and a synchronous with the transmitter cycle of pulses, and generates a coincident cycle of pulses that add an additional contains the pulse immediately following the last match pulse, a receiver oscillator, one like the transmitter Number of master values, the size of which is proportional to the corresponding master values on the transmitter is, a control circuit for each conductance to connect the latter in shunt or to separate, with all control circuits' are set up on the receiver so that they an additional pulse of the receiver pulse generator cycle substantially simultaneously received with the first pulse in the cycle to switch off all master values, Means to transfer the connected conductance values with local oscillation current via the control circuits to supply, means to each control circuit and a parallel connected polarity and amplitude detector the received To supply pulses, the received polarity pulse with the polarity pulse The receiver pulse generator works together to adjust the phase of the conductance values applied local oscillatory current to determine the additional received Code pulses in the associated control circuits with the corresponding pulses of the Receiver pulse generator work together to the conductance of the receiver in the same compilation as it exists in the transmitter, to be connected in parallel so that one of the original amplitude of the transmitted vibration proportional current from the local Oscillation frequency flows through the parallel conductive circles, a homodyne detector circuit, which absorbs the current of local oscillation frequency to one of the certain instantaneous amplitude of the vibration to be transmitted proportional display pulse and means for compiling the successive, restored amplitude values to produce a Playback of the transmitted waveform. 12. Transmission system according to claim 11, characterized in that the homodyne detector circuit completes one of the conductance values the resistor and a filter containing the one additional pulse in the pulse cycle of the receiver pulse generator the potential developed at the terminating resistor to the Compilation means leads. References: W. R. Benett: Bell Systems technical Journal (1943) »pp. 446 to 472; U.S. Patents Nos. 2,508,622, 2,464,607, 2,508,622. For this purpose 3 sheets of drawings I 5462 9.53