DE1031367B - Circuit arrangement for the coded transmission of identifiers, in particular numbers, in systems of communication technology - Google Patents

Description

In communication technology there is often the task of converting certain identifiers into a code, because there are many Characteristic practically only a few, mostly only two transmission lines are available. That is for example the case when digit values, e.g. B. in the form of certain potential levels, from a memory to a selector setting set or from a keypad for keypad selection to a Register should be transferred.

Solutions to this problem are already known. According to British Patents 398 812 and 684 608 are z. B. positive and negative different potential levels via rectifier branches evaluated with the help of several relays. These known circuits require considerable effort on components both for the evaluation and for the potential reversal.

A circuit arrangement has also been proposed which, with the aid of two series-connected Relay can convert four potential levels into a binary code and when used twice this circuit to transmit four code digits four times over two lines and as a binary code are to be evaluated. However, this proposed circuit has the shortcoming that as a result of the series connection the relays must always meet a certain fault current condition. This fault current condition can not be complied with without further ado, especially if the transmission cores have a have high line resistance. Another shortcoming of this circuit is that one of the two relays is bridged with a directional conductor, so that it is only dependent on a certain Current direction can be excited. Another major disadvantage of this circuit is that - due to the circuit structure - a response delay cannot be avoided. Longing Response times must, however, especially in electronically or partially electronically operated message switching systems be avoided. Even in cases of rapid information, e.g. B. when choosing the keyboard, The fastest possible evaluation is to be demanded in order to avoid that the information is given faster than the information evaluation takes place.

The invention now relates to a circuit arrangement for the coded transmission of identifiers, in particular numbers, via two lines and output of the identifiers or numbers in the form of a dual code, in which four potentials are available per line to represent the numbers and are transmitted in a correspondingly combined manner . Such a circuit arrangement eliminates the deficiencies described according to the invention in that three Ver circuit arrangements are coded
Transfer of license plates,

especially of numbers,
in systems of communication technology

Applicant:

Siemens & Halske Aktiengesellschaft,

Berlin and Munich,
Munich 2, Witteisbacherplatz 2

Dipl.-Ing. Heinz Mertel, Hohenschäftlarn near Munich, has been named as the inventor

stronger, preferably transistor amplifiers, are connected with their control electrodes to each line and that in the output circuit of the first amplifier the winding of a relay and in the output circuit of the third amplifier has a reverse winding of the same relay, while in the output circuit of the second Amplifier a further relay is provided and each amplifier is biased so that it is of a certain potential level is activated, whereby when the first amplifier is activated, the first Relay is energized while both relays are energized when the first two amplifiers are activated, and when all three amplifiers are modulated as a result of the opposing winding of the first relay being excited second. Relay responds alone.

The invention is explained in more detail with reference to FIGS. 1 and 2 of the drawing, namely shows

1 shows a circuit arrangement according to the invention and

FIG. 2 shows a table to explain the dual that can be implemented with the aid of the circuit according to FIG. 1 Codes.

Fig. 1 shows a circuit according to the invention with two analog transmit and receive stages S1, S2 and El, E2. The device pair Sl, El is connected to the wire α of a message switching system, while the device pair S 2, E 2 is connected to the wire & of such a system. Since both pairs of equipment are structured and effective in the same way,

809 529/178

Claims (2)

tion of the invention only the pair of devices Sl, El are described in more detail below. The potential levels are tapped at the transmitter 5Ί and transmitted via wire a, which has the line resistance Ra . In a manner known per se, the transmitter consists here of a voltage divider made up of the resistors Wl, Wl, WZ, Wi, and the potential levels are tapped via contacts fei, k2, k3. The voltage divider is between earth and -60 V. Since the status: »no potential on wire α« ίο is evaluated, the three contacts k 1 to k 3 are sufficient to represent four potential levels. B. can be operated by pressing a button or via relay. On the receiving side, three transistors TAl, TB, TA2 are connected to the wire α via the limiter resistors RA1, RB and RA 2. The transistors are operated here in an emitter circuit and their emitters are connected to different reference voltages. These comparison voltages are taken from a voltage divider from the resistors W5, W6, W1 and W8 . This voltage divider is also between earth and -60 V. All transistors TA 1, TB, TA2 are connected to a common blocking voltage via the resistor W9 when the wire is floating ο. In the output circuit of the transistor amplifier with the transistor TA 1 is one winding A 1 of the relay A. The opposite winding A 2 of this relay A is in the output circuit of the transistor TA 2. In the output circuit of the transistor TB is the second relay B. The other winding end of the above Relay is connected to -60V. The circuit according to the invention now operates as follows: k When the contact 1, the transistor TA 1 is modulated, and thus the winding is energized Al. Is now k 2 is closed and thus the transistor TB Driven of the contact, which is of this level of potential from conducting, thus said in the output circuit of the transistor TB to the relay B. Relays A and B are thus energized when contact k 2 is closed. The further statement represented by the energized state of the relays, namely that relay J5 alone is energized, is achieved in that when contact k 3 is closed, transistor TA 2 is also made conductive, so that opposing winding A 2 of relay A is energized . Thus, the effects of the two windings A1 and A 2 of relay A cancel each other out, and only relay B is energized. The device pair 6 "1, E1 is suitable for evaluating four potential levels in the form of a dual code. Accordingly, it can be used as an independent unit if necessary. However, in order to be able to evaluate more than four identifiers, for example ten digits, in a message switching system, two circuits according to the invention are used which are connected to two lines. Fig. 1 shows such an extension through the pair of devices S2, E2 lying on the wire B. This device pair works in the same way as the device pair Sl, El. The interaction of the two pairs of devices will now be explained in more detail with reference to FIG. Fig. 2 shows in the left column the digits 1 to 16 to be evaluated and in the first row the relays A, B, C, D of the two device pairs Sl, El and S2, E2. In the individual lines of the table, a + sign indicates which relays A, B, C, D are energized for the relevant digit. A —character indicates which relay is not energized for that digit. The numbers 1 to 16 are thus identified by the energized states of the relays A, B, C, D. Relay A has value 1, relay B has value 2, relay C has value 4 and relay D has value 8. From this it follows e.g. B. for the number 11 that the relays A, B and D must be energized (1 + 2 + 8), while relay C is not energized, which can also be seen from FIG. Corresponding combinations can also be found in Table 2 for the other digits. The invention is not restricted to the generation of the potential steps, as described for example, by taking off from a voltage divider. It is also possible to tap the potentials on a chain of resistors of different heights and to select the resistor W9 correspondingly smaller so that the line resistance Ra or Rb is included in the voltage division between the potential levels and the blocking potential. The required voltages can easily be derived from the battery values available in an office. Godfather ta ν saying ε-1. Circuit arrangement for the coded transmission of identifiers, in particular numbers, over two lines and delivery of the identifiers in the form of a dual code, in which four potentials are available to represent the numbers per line, which are transmitted in a correspondingly combined manner, for systems of communication technology, characterized that three amplifiers, preferably transistor amplifiers (TAl, TB, TA2), are connected with their control electrodes to each line (α, b) and that the winding (AT) of a relay in the output circuit of the first amplifier and a counter-winding in the output circuit of the third amplifier (A2) of the same relay, while another relay (B) is in the output circuit of the second amplifier, and that each amplifier is biased in such a way that it is activated from a certain potential level, whereby the first relay is energized when the first amplifier is activated , while both relays are energized when the first two Ve r more are activated, and when all three amplifiers are activated, the second relay responds alone as a result of the opposing winding of the first relay being excited. 2. Circuit arrangement according to claim 1, characterized in that the potentials such be combined that the respective state of the total of four connected to the amplifier Relay represents a dual code. 1 sheet of drawings © 809 529/178 5.