Magnetometers began to be found in the Russian "Geranium" - and the instruments are placed in the tail part or in the vertical stabilizer (keel) of the UAV. "I was again at one of the research sites for Russian weapons and their components. Constant systematic work on their research continues. I will then take this information to sanction work. Interestingly, it's a magnetometer that they started putting in the tail/keel of Geranium," wrote the President's authorized officer for sanctions policy Vladislav Vlasyuk. A magnetometer is specifically used to measure the strength, direction, or other characteristics of a magnetic field. It can also act as a digital compass and help the UAV navigate the Earth's magnetic field. More details - in the link.