Operational Characteristics of the 175-GHz Continuous-Wave Clinotron

The operational characteristics of a watt-level water-cooled 175-GHz continuous-wave (CW) clinotron are studied experimentally and discussed in this article. The oscillator is designed to work either in the broad frequency range (161–175 GHz) and moderate output power (10–200 mW) or in a high-power regime, which has a maximum power of 0.85 W at 174.6 GHz and up to 1.2 W at 171.4 GHz. The radiation power and the frequency can be tuned by changing an acceleration voltage and a beam current. The studies are focused on the long-term drifts of the output power and frequency during a free-running operation of the clinotron. In particular, the influence of a beam current and a cooling water temperature on the frequency is considered and the contribution of both effects is discussed. The maximal variations of a power level and an oscillation frequency observed within 1 h are less than
$3\times 10^{-{2}}$
and
$5\times 10^{-{5}}$
, respectively.