result a night vision riflescope is activated and the time of its active work i e the time during which it is switched on is measured and added to the previously accumulated total time of the active work which is stored in the nonvolatile memory unit 48 at the same time the data processing unit 46 of the first set of the elements sends a command to the data processing unit 56 of the second set of the elements for separately counting and storing in the nonvolatile memory unit 64 the number of shots produced from the firearm irrespective of the operation of the night vision system and in the nonvolatile memory unit 66 the number of shots produced during the working time of the night vision system i e with muzzle flashes that can affect the light sensitive elements of the night vision system when it is necessary to display the information about the total number of shots the accumulated time of active work of the night vision system and about the number of shots produced during operation of the night vision with the damaging effect of the muzzle flashes first the push button 88 of the data receiving unit 74 is pushed on for activating the elements of this unit then data processing units 56 and 46 are activated by pushing on the button 31 fig3 for retrieving the aforementioned information from the respective memory units 64 66 and 48 and for transmitting the retrieved data via the transmitters 72 and 44 to.