DE741184C - Electrical discharge vessel for short waves with capacitor to balance the mutual capacitance of the electrodes - Google Patents

Description

Electric discharge vessel for short waves with capacitor for Balancing the Mutual Capacitance of the Electrodes The invention relates to to an electrical discharge vessel - for short waves with a capacitor for balancing the mutual capacitance of the electrodes.

For the use of electrical discharge vessels for short waves it is important that the capacity between , the electrodes, especially the capacitance between control grid and cathode, is exactly the same size. This is especially important when the capacity is between Control grid and cathode should be used directly as grid circle capacitance. The size of the electrode capacitance is significantly influenced by the arrangement the electrode carrier and the supply lines. The capacity values are particularly strong by routing all wires through a common cable, which is normally the practice Pinch foot and base affected. It is known that the bushings are removed from the socket to diminish. Furthermore, the grid wires and the cathode wires are spatially available Melts that are far apart from one another are led to the outside.

It is also already known to have a capacitor in the base plate to accommodate the base, but it is with these known discharge vessels not possible, the capacitance of the capacitor after the discharge vessel has been assembled to change with the socket.

Despite the most careful dimensioning and arrangement of the electrodes, it is such an equality of capacities, as is particularly the case for tubes of one type of great importance has not been reliably achieved. The values fluctuate for tubes of the same type up to 15%. The task at hand for all tubes of the same Design same capacities to get the electrodes against each other, is achieved by the invention in a simple manner.

It is also already known within the base of discharge vessels to arrange adjustable capacitors. However, such a tube is only extreme difficult to manufacture. In addition, the arrangement requires considerable space as well an extension of the supply lines and thus an increase in capacities, what however, it is undesirable for shortwave tubes.

According to the invention, electrical discharge vessels for short Waves for balancing the capacitance of one or more of the electrode leads with metal coverings attached to the base plate made of insulating material connected and these metal coverings by mechanical processing to the desired Brought value. By this measure, balancing capacitors are obtained. To match the capacitance of such a capacitor to a desired value are now the metal coverings by simple mechanical processing, such as grinding chemical treatment or otherwise brought to such a size that the Total capacity of the tube is the same in each case.

If necessary, with the arrangement according to the invention, assignments, which should together form a capacitor, on different sides made of insulating material attach the existing base plate.

In most cases, the capacitor surfaces do not need to be cover, since the required adjustable capacity is only very small. It is sufficient, for example when moving from one connector pin towards the other one provides a small metal surface. Under certain circumstances, however, it is advantageous that also from the other connector pin in the direction of the former a corresponding metal assignment is provided.

If necessary, the assignments, preferably after matching, are provided with an insulating varnish coating to increase the creepage distance.

In the drawing, an embodiment is schematically shown in FIG Invention shown. In the insulating plate z of an electrical, not shown Discharge vessel, for example made of a low-loss ceramic material can exist, contact pins of the control grid G1 and the cathode K are in per se used in a known manner. The metallic base plate carries on the contact pin G1 of the control grid on the upper side and on the contact pin 1i of the cathode on the lower side metallic coverings 2, which are based on one of the known methods the ceramic body can be applied.

For the final and exact adjustment of the capacity to a desired one These metallic coverings can add value, for example, by grinding off part of them Surface can be reworked. The grid entrance circle is now shown in the Figure indicated circuit through the inductance L1 and through the capacitance formed between the grid and cathode on the one hand and the coverings 2 on the other hand. A precise balancing of the various tubes of the same type is possible through the provision of the additional adjustment capacitor, which is easily accessible from the outside, in a simple way Way possible.

Claims (1)

PATENT APPEAL: e.g. Electrical discharge vessel for short waves with a capacitor for balancing the mutual capacitance of the electrodes, characterized in that, to balance the capacitance, one or more of the electrode leads are connected to metal coverings attached to the base plate made of insulating material and these metal coverings are mechanically processed to the desired value are brought. Electrical discharge vessel according to Claim r, characterized in that those coatings which together form a balancing capacitor are arranged on different sides of the base plate. 3. Electrical discharge vessel according to claim z and 2, characterized in that the assignments, 'preferably after the balancing, are provided with an insulating varnish coating. 1 To distinguish the subject of the application from the state of the art, the following publications were considered in the granting procedure:. Austrian patent specification. . ; 1r. 145,989; British - 285799, 470 685, 466 54 2 , 473 574; American patent \ r. 1,923,552, 1,683,202; Issue 5 Condensa-Tempa of the Hermsdorf-Schomburg Isolatorengesellschaft, July 1935, p. 18, 19. -