DE2005312C - Electronic receiving circuit within a teleprinter - Google Patents

Description

In the case of teletype operation in the telex network, the receiving subscriber is informed about the release of the connection signaled by continuous start polarity. The machine, which then runs out, prints after it has detected it Closing sign by undefined creation of a holding circle from a missing sign. This missing character is perceived as annoying in many cases.

Such missing characters arise from the fact that the triggering of the mechanical printer after termination the reception process takes place automatically. With a continuous machine with mechanical In the reception converter, it is very difficult or imperfect to print these missing characters impede. So far such misprints have been accepted as a rule.

The invention is based on a teleprinter with electronic circuitry for the serial parallel converter of the receiver that works together with an electromechanical printing unit, the clock signals generated by a clock generator controlling both the load on the start-up step and the cycle time of the receiver designed as a shift register with a whole multiple of the frequency of the step clock and store the information in each case from the middle of the last characteristic step by means of a blocking circuit for a predetermined time, as it is e.g. B. is known from the German OfTenlegungsschrift 1907013, wherein a receiving switch is provided which converts the receiving teletype steps into logical signals. In such a teleprinter the impression of Fthlzeichen this origin according to the invention dadu ^r ch avoidable that between the receiving switch and forming a shift register series-parallel converter, a bistable flip-flop nu Vorbereitungseinsanc is cased so that associated with the Verbindunesabbau change of the potential conditions on the input line of the Serienparallelumseuer is blocked until one is assigned to the transition from stop to start polarity = control edge is received.

An exemplary embodiment of the subject matter of the invention is described below and in Drawing shown. It shows

Fi g. 1 is a basic circuit diagram of a Empfangsu, setter for five code characters with start and Spe ^r rschritt in a teleprinter with additional -. Chaltmitteln for preventing the impression of incorrect characters of said source, Figure 2 is a time chart at Figure 1...

The incoming in series teleprinter characters from reaching the Femschreibmaschine a ^c:; Telegraph relay simulating electronic receiving circuit E as so-called logical signals:., Ie separation step = 1st character step = 0, in there shift registers formed by flip-flops KS, K4, Ki, Kl, Kl, KAn ur, ' KSp , with the flip-flop - Kl to A'5 the five characteristic steps of the telex character, the flip-flop KAη is assigned to the start-up step and the flip-flop ^ p is assigned to the locking step. An additional circuit consisting of two flip-flops K 11 and KU and two NAND gates Gl and Gl is switched on according to FIG. Between the input switch ES and the a: shift register designed electronic serial converter with the first-mentioned flip-flop. This will make the recipient be ^; Permanent character stream blocked until a new ■ edge from Stop to Siart Pularity is received. When the connection is established, there is stoppage (= log 1) at the receiver input £ in pauses in writing. A bistable multivibrator XIl with preparatory input ensures the correct phase transfer of the polarity relationships at the time of the generator cycle (24 kHz), but is of no significance for the logic. With log 0 at the output £ ', there is also log 1 at the input E * of the shift register, i.e. the same signal! as at the input E. The blocking of the information at a NAND logic element Gl is taken over by another such trigger stage if the criterion S briefly changes from log 0 to log 1 in the blocking step and the input E is at log 0. In the case of flip-flop K 12, it must be taken into account that the NAND logic element G 2 is connected to the static input, which has a priority over the preparation input and sets the output Q to log 0. The starting position is set by log 1 at the preparation input of this stage after a positive edge on the clock supplied by the trigger stage All. The shift clock for the shift register is denoted by St.

From Fig. 2 shows the time dependency of the recipient release or recipient block Eg on the type of incoming characters, ie on the fact whether any telex characters Z1, Z 2 or Z 3, final characters SZ or no characters are received. The 32nd combination of the international CCITT alphabet No. 2 is also designated with K32 , which, as is well known, does not result in an imprint.

1 sheet of drawings

Claims (1)

Palent claim: Electronic circuit arrangement within a teleprinter machine for the serial parallel converter of the receiver that works together with an electromechanical printing unit. wherein the clock signals generated in front of a clock generator with a whole multiple of the frequency of the S1. ittaktcs control both the scanning of the start-up step and the cycle time of the receiver * designed as a shift register and store the information from the middle of the last characteristic step by means of a blocking circuit for a predetermined time, as well as with a receiving switch that converts the received transcripts into logical signals, characterized in that a bistable multivibrator (K 12) with a preparation input is switched on between the receiving switch (ES) and the series-parallel converter forming a shift register so that when the connection is disconnected, the change in the potential ratio * on the input line of the series-parallel converter is blocked until one Control unit assigned to the transition from stop to start polarity is received.