Avramidis, K. A., Ioannidis, Z. C., Aiello, G., Chelis, I., Dinklage, A., Gantenbein, G., et al. (2019). Progress in the Development of a 1.5 MW, 140 GHz Gyrotron for the Upgrade of the ECRH System at W7-X. Talk presented at US-EU-JPN RF Heating Technology Workshop: Workshop on RF Heating Technology of Fusion Plasmas 2019. Freiburg. 2019-09-09 - 2019-09-12.