Choosing a cut frequency
Both of these measures lead to a decrease in sensitivity, or, in other words, a larger number of plates are required to maintain sensitivity. In the practical structures of the tubes, the cut frequency in accordance with the requirements for the form of the deployed voltage is selected as low in order to obtain the highest sensitivity with minimal complications.
The choice of cutting frequency determines the delay time of the T of each section, and, therefore, for this value of impedance Z0, the container from the section can be determined. The characteristic impedance Z0 is usually selected in such a way as to achieve coordination with the impedance of the coaxial cable; Inputs to the deflecting system are performed in the form of coaxial nests or chips welded into the glass balloon of the tube.
The electronic beam described by the pier was designed to obtain the maximum possible sensitivity in combination with an acceptable bandwidth strip. The tube had the following data:
To obtain a very small diameter of the spot, a small beam current was taken. Therefore, due to insufficient brightness, only periodic signals could be investigated.
In such deviant systems, it is necessary to load the filter of low frequencies with a resistance equal to its characteristic impedance. Otherwise, the running wave will affect the end of the filter and cause a false deviation of the spot on the pipe screen. The load resistance can be mounted inside the tube cylinder.
Deflecting system with a running wave with distributed constant. Above, an analysis was carried out for the case when the connecting conductors between the neighboring pairs of the deflecting plates were presented in the form. concentrated inductances. You can make a simple transition from such a system to a deflecting system in the form of a transmission line consisting of two parallel flat stripes, the length of which and the distance between them are selected so as to obtain the necessary characteristic impedance.