(АКС74Н), АКС74УН, АСС, RPKN-1 (RPKSN-1), RPK74N (RPKS74N) machine guns, PKMN-1 (PKMCH-1), SVDN-1, VSS sniper rifles, RPG-7N1 (RPG-7N1 manual anti-tank grenade launcher) ) and observation of the battlefield in natural night light.
The night sight NSPU-3 is operated at an ambient temperature of plus 50 to minus 50 degrees and a relative humidity of not more than 98% at a temperature of 40 degrees. Provides on a clear moonless night with natural night illumination and a transparent atmosphere, when the targets are located on the background of an open green meadow, the detection of targets and direct fire at direct ranges of all types of weapons indicated above.
The recognition range provided by the NSPU-3 sight depends on the amount of natural night illumination, the transparency of the atmosphere, and the contrast between the target and the background. With increased illumination, on a moonlit night, if there are external lights, if the target is located on a light background (sand, snow), the recognition range increases.
In low light, low cloud cover, low atmospheric transparency, if the target is located on a dark background (arable land, tree trunks, etc.), the recognition range is reduced. The following types of power sources were used to power the NSPU-3 sight: five D-0.55S GOST 11258-79 batteries, section 5РЦ83Х ФШ0.351.929ТУ.
The general device of the sight of the unified night NSPU-3.
The main components of the NSPU-3 sight are a lens, an electron-optical transducer (EOP) U1, an eyepiece, and alignment mechanisms in height and direction. The sight has the following controls: handwheel BRIGHTNESS OF THE GRID OFF turning on the sight and adjusting the brightness of the grid, handwheel DOWN STP UP of the alignment mechanism in height, handwheel LEV STP RIGHT of the alignment mechanism in the direction, focusing ring of the image intensifier tube.
A desiccant, a nipple closed by a lid, a lid covering the accumulator battery, and a clamping device are fixed on the sight body. A plug is located in the ocular part of the body, and an eyecup is fixed. The dehumidifier is designed to dry the air inside the sight during operation. Unsaturated silica gel desiccant has a bluish color. When fully saturated with moisture, the silica gel acquires a pale pink or off-white color, which indicates the unsuitability of silica gel for further use.
The nipple serves to purge the internal cavity of the sight with dry nitrogen or air. Nitrogen or air, when purging, exits through a hole closed by a plug. The NSPU-3 sight is mounted on a weapon using a clamping device consisting of a bracket, a clamping screw, a latch, a handle, and a handle. The eyecup facilitates the orientation of the eye relative to the exit pupil of the sight and protects the eye from accidental damage.
The focusing ring of the image intensifier tube is designed to obtain a clearer image of the target at different recognition ranges, when reconciling the alignment target and to compensate for the defocusing of the image intensifier when the temperature changes from minus 50 to plus 50 degrees. The main power source for the NSPU-3 sight is a rechargeable battery consisting of five D-0.55C GOST 11258-79 batteries, connected in series. The backup power source for the NSPU-3 sight is the 5РЦ83Х ФШ0.351.929ТУ section installed in the container.
Sight reticle of the sight of the unified night NSPU-3.
In the field of view of the NSPU-3 sight (with angular dimensions in thousandths), sighting marks are applied to the reticle, the top row of which is used to aim up to 300 meters when shooting from an RPG-7N (RPG-7DN) grenade launcher and when firing from other types of weapons, specified in section 2 of this manual for all ranges according to the scales of aiming angles.
The dashes indicated by the number 4 serve for aiming when firing from a grenade launcher at a range of 400 meters. The bottom line is 500 meters. When firing from a grenade launcher with a PG-7L grenade, the top row of sighting marks serves to aim at a range of 150 meters. Strokes marked 2L – for aiming at a range of 200 meters and the bottom stroke – at 300 meters.