Krier, L., Avramidis, K., Braune, H., Gantenbein, G., Illy, S., Jelonnek, J., et al. (2022). Progress on the Frequency Stabilization of MW-Class 140 GHz Gyrotrons at W7-X with a Phase-Locked Loop. Talk presented at 21st Joint Workshop on Electron Cyclotron Emission (ECE) and Electron Cyclotron Resonance Heating (ECRH) (EC-20). Saint-Paul-lez-Durance. 2022-06-20 - 2022-06-24.