We study the oscillation regimes for the model of a gyrotron with a fixed Gaussian longitudinal field structure and three modes of an equidistant spectrum (an operation mode and two satellites symmetrically spaced by frequency) during autonomous operation and under the action of an external monochromatic signal. The two-parameter (dimensionless current and the cyclotronresonance mismatch for an operating mode) plane is partitioned into the regions corresponding to various regimes. It is shown that the presence of a maximum at the leading edge of the voltage pulse can lead to excitation of the parasitic modes in the process of the power-source switch-on and to quenching of oscillation of the operating mode. These undesirable effects can be suppressed by locking the operation-mode frequency by an external monochromatic signal, which provides oscillation at the operation mode.

我们研究了在自主运行和外部单色信号作用下，具有固定高斯纵向场结构和等距谱的三种模式（一种工作模式和两颗频率对称间隔的卫星）的旋流器模型的振动状态。将两参数平面（对于工作模式，无因次电流和回旋共振失配）平面划分为与各种状态相对应的区域。结果表明，在电压脉冲的上升沿处存在最大值会导致在电源接通过程中激发寄生模式，并导致工作模式的振荡猝灭。通过使用外部单色信号锁定工作模式频率，可以抑制这些不良影响，