Sura Ionospheric Heating Facility

The Sura Ionospheric Heating Facility, located near the small town of Vasilsursk about 100 km (60 miles) eastward from Nizhniy Novgorod in Russia, is a laboratory for ionosphere research. Sura is capable of radiating about 80 megawatts at 4.3 MHz, increasing to 260 megawatts at 9.5 MHz.

Source: Wikipedia — Sura Ionospheric Heating Facility (CC BY-SA 4.0)