SU49758A1 - Modulator of the magnetron generator - Google Patents

Description

The device proposed in accordance with the invention is based on the principle of combining the functions of generator and modulator lamps in one object.

It is known that oscillations in magnetrons occur when the so-called critical field is determined from the equation

6,

I r

The specified magnetic field H remains critical if the ratio

Kka

remains constant.

In other words, for different anode diameters located around a single filament, for a given magnetic field, the critical conditions will be maintained at a constant ratio

to,

i.e., having reduced, for example, the anode radius by a factor of ten, we must reduce the anode voltage by a factor of a hundred (in order to maintain critical conditions).

Based on the above, a magnetron oscillator design is proposed that combines a modulator lamp simultaneously.

In FIG. 1, 2 and 3 depict the proposed device in three versions.

The magnetron consists of a filament K (Fig. 1), covered by a cut anode A, both half rings of which are interconnected by a loop L, and two modulating cylindrical electrodes t and t, covering the cathode coaxially with the anode. The electrodes t and / I2 are connected to one of the clamps of the modulation transformer, the other clamp of which is connected to the cathode. The letters M and B in the drawing show, respectively, a microphone and an amplifier connected to the primary winding of the modulation transformer.

The modulating electrodes can be switched on in a push-pull pattern, as shown in FIG. 2 and 3. In this case, the electrodes t and t are connected to the ends of the secondary winding of the modulation transformer, and the midpoint of this winding is connected to the filament of the magnetron.

In order to correct the modulation characteristics, the modulating electrodes can be made in the form of truncated cones, with their bases directed toward the anode of the magnetron (Fig. 3).

While the microphone M is not working, the magnetron oscillates normally. When the microphone is turned on, electric fields are imposed between the modulating electrodes t and t, as well as between the latter and the filament of the magnetron.

These electric fields, for which the magnetic field of the generator may be less critical, affect the flow of electrons and, thus, the oscillating power of the magnetron. Thus, the magnetron oscillator is modulated.

As shown by the tests performed, the proposed device achieves the necessary linearity between the current on the modulating electrode and the anode current, i.e., the oscillating current.

The subject of inventions.

Claims (3)

1. A magnetron generator with a cut-off anode, characterized in that the magnetron is provided with one or two cylindrical modulating electrodes covering the cathode coaxially with the anode and connected to one of the terminals of the modulation transformer, the other clip of which is connected to the cathode. 2. The use of modulating electrodes of conical shape in the modulator according to claim 1 in order to correct the modulation characteristic. 3. The use of modulator in PP. 1 and 2 push-pull circuit for switching modulating electrodes. FIG. 1 yes FIG. 2