JPH0479128A - Multi-stage depressed collector for microwave tube - Google Patents

Abstract

PURPOSE:To realize a multi-stage depressed collector in which the number of electrons returning to interaction portion is small by connecting at least one electrode to a lead wire through a resistor. CONSTITUTION:A voltage Vh is applied to a helix 1 through a helix lead wire 6, a voltage Vcl to a first collector electrode 2 through a first collector wire 7 a voltage Vc2 to a second collector electrode 3 through a resistor 9 by a second collector lead wire 8. At that time, the electric potential of a second collector electrode 3 in which the number of electrons returning to the helix 1 is small is lower than the constant voltage Vc2 of the second collector electrode 3 which is generated in a power supply. In that case, the appropriate resistor 9 is interposed between the second collector electrode 3 and the second collector lead wire 8, and the actual voltage applied to the second collector electrode 3 is a voltage V'c2 lower than the voltage Vc2 of the power supply by a voltage drop which is determined by the resistor 9 and a current flowing therethrough and the return electron at the multi-stage depressed collector enter into the first collector electrode 2 like electron beams 10d thereby being able to realize the multi-stage depressed collector in which the number of return electrons is small.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a multi-stage potential drop collector for a microwave tube.

[Conventional technology]

Among the methods for improving the overall efficiency of microwave tubes such as helical traveling wave tubes, it is well known that a method of operating by setting the collector potential lower than the helix voltage is particularly effective. In particular, in recent years, there has been a strong demand for helix-shaped traveling wave tubes to improve overall efficiency due to demands for smaller, lighter weight, and lower power consumption of devices that use traveling wave tubes. A multi-stage potential collector is employed that captures electrons according to the velocity distribution of the electrons that have completed the interaction between the electron beam and the circuit wave at the interaction section with the circuit wave.

Next, the conventional technology will be explained using a two-stage potential drop collector of a helical traveling wave tube as an example.

FIG. 2 is a sectional view of a main part of an example of a conventional two-pronged potential drop collector for a microwave tube.

In Fig. 2, 1 is a helix, 2 is a first collector electrode, 3 is a second collector electrode, 4 is a vacuum envelope, 5 is a case, 6 is a helix lead wire, and 7 is a first collector lead. 8 represents the second collector lead wire, 10 represents the electron beam, and 11 represents the central axis.

As shown in FIG. 2, in this configuration, the first collector voltage 8i! 2 and the second collector electrode 3, the first collector electrode voltage ■ is applied to the helix 1 via the helix lead wire 6, and the voltage ■h is such that Vh>Vcl>Vc2 holds true. 1 and 2nd collector electrode voltage ■. 2 is applied via the first collector lead wire 7 and the second collector lead wire 8. The electron beam 10 that has completed the interaction with the high frequency at the helix 1 has various velocity components, and depending on this velocity, the electron beam 1 has a slower velocity.
The electron beam 0a is distributed to the first collector electrode 2 having a high potential, and the fast electron beam 10b is distributed to the second collector electrode 3 having a low potential.

The basic requirements for this multi-stage potential reduction collector for microwave tubes are that the potential of each collector electrode is determined so as to minimize the power consumption of the entire collector, and that the high-frequency characteristics of the microwave tube It is desirable to minimize the number of return electrons that have an adverse effect on the electron beam, that is, electrons that once enter the collector and return to the helix l side, as in the electron beam IOC shown in FIG.

[Problems to be Solved by the Invention] However, in this conventional multi-stage potential reduction collector for microwave tubes, the potential of each collector electrode depends on the velocity component of electrons at interaction parts such as hesocks, and therefore, The optimal collector potential for reducing the power consumption in the collector as much as possible and reducing the number of return electrons to the interaction part varies considerably from one tube to another.

On the other hand, in a power supply for applying a potential to a multistage potential drop collector, it is easier to fix the generated voltage rather than making it variable. Further, even when using a microwave tube, the work of adjusting the voltage is troublesome, which is not preferable from the viewpoint of maintenance of the device.

Therefore, as a microwave amplification device including a power supply, it is preferable that a multistage potential collector operates at a fixed constant operating voltage. However, there was a problem in that the electrode could not be operated at the optimal electrode potential with respect to the return electrons.

An object of the present invention is to provide a multi-stage potential reduction collector for a microwave tube, in which the multi-stage collector can operate at an optimal electrode potential with respect to return electrons.

[Means to solve the problem]

The present invention provides a multi-stage voltage drop collector for a microwave tube comprising a plurality of electrodes each connected to a lead wire, in which at least one of the electrodes is connected to the lead wire via a resistor.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view of a main part of an embodiment of the present invention.

In FIG. 1, 1 is a hexock, 2 is a first collector electrode, 3 is a second collector electrode, 4 is a vacuum envelope, 5 is a case, 6 is a helix lead wire, 7 is a first collector lead wire, 8 denotes a second collector lead wire, 9 a resistor, 10 an electron beam, and 11 a central axis.

As shown in FIG. 1, in this configuration, helix 1
A voltage V is applied to the first collector electrode 2 through the helix lead wire 6, a voltage Vcl is applied to the first collector electrode 2 through the first collector lead 7, and a voltage Vcl is applied to the second collector electrode 3 through the resistor 9. . 2 is applied by the second collector lead 8.

At this time, in this multistage potential reduction collector, the potential of the second collector electrode 3 with the least number of return electrons to the helix 1 is lower than the constant potential V(,2) of the second collector electrode 3 generated by the power supply. In this case, a suitable resistor 9 is placed between the second collector electrode 3 and the second collector lead wire 8, and the voltage actually applied to the second collector electrode 3 is lower than the potential VC2 of the power supply. A voltage V'e2 that is lower by the potential drop determined by the current flowing therein is applied, and at this time, the returning electrons such as the electron beam 10c in the multi-stage potential drop collector shown in FIG. Since the electrons enter the first collector electrode 2 as shown in 10d, a multi-stage potential drop collector with few return electrons can be obtained.

In this embodiment, the resistor 9 is built into the case 5, but this has the advantage that the heat generated in the resistor 9 can be easily cooled by using collector cooling air or the like.

Here, considering a helical traveling wave tube that employs a two-stage potential drop collector that operates in the 14GH2 band, the helix voltage ■□ is 8 kV and the operating current is 200 mA, and the potential VCI of the first collector electrode 2 determined by the power supply is 4kV
, the potential of the second collector electrode 3 is 2 kV. At this time, the current ■cl flowing through the first collector electrode 2 is 50
mA, the electrode current flowing to the second collector electrode 3. 2 is 150
Let it be mA. However, in reality, the optimum operating condition in which fewer electrons return to the hexock 1 of the collector is that when the voltage of the second collector electrode 3 is 1900V, which is 100V lower than 2kV, the second collector electrode 3 and the collector of the second collector If a resistor 9 with a resistance value of 0 and 15 is placed between the lead wires 8, the potential V' is actually applied to the second collector electrode 3. 2 is 1900V and can operate with the least number of return electrons.

In this embodiment, a two-stage potential drop collector of a helical traveling wave tube was explained as an example, but it is clear that the present invention can be applied to a multi-stage potential drop collector having two or more stages.
Furthermore, it is clear that the same effect can be expected by arranging the resistor between a plurality of electrodes and the lead wire instead of one electrode. Further, it can be easily inferred that the resistor is a variable resistor.

〔Effect of the invention〕

As explained above, the present invention provides a multi-stage potential reduction collector for a microwave tube, by arranging a resistor between at least one electrode and the lead wire, even when using a power supply with a fixed voltage applied to the collector. By selecting the values of the resistors so that the multi-stage potential-dropping collector operates at a collector potential at which the multi-stage potential-dropping collector operates under optimal conditions, it is possible to obtain a multi-stage potential-dropping collector with fewer electrons returning to the interaction part.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a main part of an embodiment of the present invention, and FIG. 2 is a sectional view of a main part of an example of a conventional bifurcated potential drop collector for a microwave tube. 1... Helix, 2... First collector electrode, 3...
- Second collector electrode, 4... Vacuum envelope, 5... Case, 6... Helix lead wire, 7... First collector lead wire, 8... Second collector lead wire, 9・・・
・Resistor, 10... Electron beam, 11... Central axis.

Claims (1)

[Claims] A multi-stage potential drop collector for a microwave tube consisting of a plurality of electrodes each connected to a lead wire, characterized in that at least one of the electrodes is connected to the lead wire via a resistor. Multistage potential drop collector for wave tubes.