What is a remote pointer in C.

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Telecommunication apparatus

[435]Telecommunication apparatus (Telecommunication device), device by means of which a process at a remote point can be made recognizable, usually using electrical current (electrical telecommunication device). Where the shouting or the gesture is no longer sufficient, the signal is used in industrial plants, in traffic systems, in the army and navy, especially the optical sign, which is provided mechanically or electrically.

Fig. 1. Schematic representation of the electrical remote pointer.

In the very practical electrical remote pointer from Siemens and Halske, a number of positions on the transmitter are connected to an equal number of positions on the receiver in such a way that each position on the first corresponds to one position and only one position on the other causes corresponding recipient position. A commutator in the form of a crank contact K (FIG. 1), the crank d of which is connected to one pole of a power source B, and any one of the three contact pieces serves as the transmitter a, o, c.

Fig. 2. Electric remote pointer. Layout.

The receiver M consists of three electromagnets a1, b1, c1whose windings are led through a common line to the second pole of battery B. The three outermost ends of the electromagnetic coils are each connected by a line to a contact piece of the transmitter. If the transmitter is now placed on a contact piece, the current is passed through the electromagnetic coil connected to this piece, so that the electromagnet in question and only this is excited. A small iron pointer rotating above the electromagnet is placed parallel to it by the attraction of the energized electromagnet, thus making the setting of the transmitter visible on the receiver. So that the signal can be given not only from one point to the other, but also from the latter to the former, in order to e.g. B. to confirm the correct receipt of the character or the execution of the order, two arrangements of the type described are merged so that each is used for one of the two directions. Electric bells W are placed in the back division at both places1, W2 switched on, which respond when the device is activated and indicate to the sender that power is available, but call the recipient.

In carrying out the principle discussed, an arrangement is used which creates a more perfect magnetic circuit. The electromagnetic coils E are on a base plate (Fig. 2 and 3)1 to E6 set up in a circle and equipped with radial, inward-pointing pole pieces. In the central space that remains free, a small armature, an equal-armed lever, rotates around an axis parallel to the magnet cores.

Fig. 3. Electromagnet with armature.

The lower ends of the electromagnets are connected in the same way and comprise a second same armature which is connected to the upper one by a shaft. Two diametrically opposite electromagnetic coils are connected in series in such a way that they face opposite poles at the top and at the bottom. If a current now passes through such a pair of coils, a strong magnetic field is created between their pole pieces at the top and bottom, and the rotatable armatures are positioned in the pole connection line. If, therefore, the crank switch is operated, it energizes the coil pairs in rows, and the armature follows its movement by always making contact between the poles concerned. In this way, six armature positions are achieved, to which six signals correspond.

Fig. 4. Ship command apparatus.

However, in order to be able to give more signals, as is usually necessary, each anchor position is not only allowed to correspond to one but several positions on the scale, each of which belongs to a special group, so that anchor position I is not just the Scale position 1, but also 7, 13, 19 etc. corresponds. The position 7 only appears when the anchor has made a full turn and begins the new turn with 7. According to this principle, the scale of the positions can be made as large as desired, because each position corresponds to a certain group and a certain anchor position in the group.

With the multiple uses of which the principle described is capable in practice, the respective form of the transmitter and the receiver will be very different. After all, the ship's command apparatus can be regarded as typical in a certain way because of its practical arrangement and its compact shape. Fig. 4 (p. 435) shows a wall mounted apparatus of this type; you can recognize the setting lever by which the commutator is operated, and the pointer of the receiver, which plays with the signal information behind the glass pane above the scale. The transmitter and receiver are thus combined into one device. Battery or machine current can be used to operate the remote pointer. In the case of the latter, the high voltage must be reduced by adding resistors. When machine power is used, two light bulbs are used to illuminate the apparatus, and they can be switched on alternately so that there is always support. See telemetry inductor.