Experimental research of frequency tuning of power pulse orotron

The well-known mechanism of frequency tuning in orotron needs to be corrected where the power devices are concerned. The first peculiarity is connected to the use of a two-row open periodic structure (OPS) that may be considered as a coupled-cavity chain having narrow (resonance) passbands. The condition of a double resonance when the proper frequency of open resonator (OR) coincides with the resonance of OPS may produce break elevation of output power and efficiency of orotron. The second effect is connected to the construction of OR in power orotrons where the length of OPS is chosen to be of the order of spherical mirror aperture. In such a case when the beam voltage augments (for given OPS period) the radiation angle is changed too increasing so-called "dynamic" diffraction losses that limit the range of orotron frequency tuning.