Ukraine and Azerbaijan signed a contract for the supply of products manufactured at the Donetsk defense plant "Topaz." We are talking about electronic intelligence station "Mail."
A brief note on "Mail" to those who are interested.
This technique is designed to detect and recognize the land, air and surface targets, while she remains unnoticed. "Mail", working on the principle of tropospheric propagation, can not only detect but also to recognize the ground (the-horizon) and air targets. Since the system is exploring in a passive mode, that is itself does not emit radio waves, it is difficult to detect. Complex "Mail" consists of three stations. It is able to accurately determine the coordinates of ground and surface targets, trace their movement to a distance of 600 km area and 150 km on the front, and air targets at an altitude of 10 km — 800 km. Radio sensitivity ranges from 110 to 155 dB / W in a panoramic view of the strip. It is provided with five antenna systems designed for different (meter, decimeter and centimeter) wavelength. The system is in service with Ukraine, Russia, Vietnam, Georgia, Turkmenistan, China and Ethiopia.