Laser Infrared Observation Device MX-9838/GVS-5

This is an infrared laser range finder.  By using IR the flash is not visible to someone down range.  There are two problems with this unit from my point of view.  First, the Neodymium YAG laser emits IR with a wavelength of 1064 nm.  This penetrates a thin layer of skin, like an eyelid and so is not eye safe.  I think that's the main reason this model is now obsolete.  The other thing is that it doesn't have a data output port to allow connection of a military GPS (PLGR, DAGR) that accepts azimuth, elevation and range data and computer the target coordinates.

This device only measures distance, i.e. it does not contain a magnetic compass function.

NSN: 5860-01-062-3543

The AN/GVS-5 is a lightweight hand-held laser rangefinder that an accurately determine the range to a target within 1 second after the FIRE button has been pressed.   The device emits a laser burst and detects its return when the burst is reflected from a distant object.  The time lapse between emission of the beam and its return is converted to meters and displayed in the eyepiece on the range-to-target display.  The entire AN/GVS-5 provides a range to the target that is accurate to within +/- 10 meters.

To use the AN/GVS-5 an observer simply aims the device by superimposing the circle at the center of the reticule pattern over the target and presses the FIRE button.  The range is displayed in the range-to-target window and remains there as long as the FIRE button is pressed.   The observer should not automatically consider the displayed range to be the correct range to the target.  On the contrary, clutter in front of or behind the target may, at times, produce false ranges.  The observer must continually associate the displayed range with a terrain-map analysis and his own range estimate to decide whether the reading is accurate.   If, in the observer's opinion, all of these figures do not correlate, he should consider the information below.

Multiple Firings

To ensure that the observer is aiming at the correct target, he should take a series of readings on the same target.  These consistent readings generally indicate that the observer has aimed in the same place each time.

Minimum Range Set

Although the emitted laser beam is relatively narrow, it is wide enough to reflect from more than one target or object.  The AN/GVS-5 has a multiple target warning light inside the eyepiece that lights when more than one return signal is received.  When multiple target readings are indicated, the range displayed is the range to the first object from which the beam is reflected.  To prevent obtaining a false reading from an intermediate object between the observer and the target the AN/GVS-5 i.e. equipped with a minimum range set (MIN RG SET).  Ranges to the nearest 10 meters and up to 5,000 meters may be set on the IN RG SET by using the variable control.  The MIN RANGE SET indicates the minimum range at which the AN/GVS-5 will register a return, thereby eliminating false readings from intermediate objects.  The observer can continue a trial-and-error process of eliminating false ranges by adjusting the MIN GR SET until the range read in the display correlates with the observers own range estimate based on map and terrain analysis.  The observer can save time in this process by establishing on the MIN RG SET the range beyond which he is certain the target lies before he begins ranging a target.  Upon completion of a mission, the MIN RG SET should always be set back to zero.

3 Jan 2011 - the minimum range appears to be 170 Yards/Meters.  That makes it harder to test the unit.  There's no solid target that far away.

Self-Location

The AN/GVS-5 an help the observer locate himself by giving him accurate distances to known points.  The observer can report these distances to his FDC, which will in turn, using graphical or computer means, give him his location.  Self-location also may be obtained by giving the FDC distances to, two burst locations of rounds that have been fired after the unit has complete4d registration.  A combination of one round and one known point may also be used for self-location.  The two points or bursts should be separated by at least 300 mills.

Adjustment of Fire

Lateral and vertical shifts in the adjustment of fire are computed by using the mil relation in the same way as adjustment of fire by using binoculars.  Range between the target and the bust and making the correction in the appropriate direction.

Target Location

The distance provided by the AN/GVS-5 should always be used with the most accurate direction to the target available and a quick, but thorough, map analysis.  The observer should remember that the AN/GVS-5 is designed to help him refine distance.  The distances determined by the device should always be correlated with known information before a target location is produced.

The PVS-6 (MELIOS) Mini Eye Safe Laser Infrared Observation Set uses the same battery as the GVS-6. 

BB-516/U

 (NSN: 6140-01-419-8191) which used Ni-Cad chemistry.

BB-326/U

 (NSN: 6140-01-533-7674) which is a Ni-MH chemistry.  300 mAh with a 3 Amp load (is this correct?)

BA-6516/U

(NSN: 6135-01-231-3498 which is a Lithium Thionyl Chloride chemistry

TS-3620

Contains a battery eliminator that is a new battery compartment cap with wires to supply DC power.

GVS-5

TM-11-5860-201-10-HR Hand Receipt
TM-11-5860-201-10 Operator's
TM-11-5860-201-20 Maintenance
TM-11-5860-201-20P 2^nd echelon parts
TM-11-5860-201-30P 3^rd echelon parts

TS-3620

TM-11-6625-2684-12  TEST SET, LASER INFRARED OBSERVATION DEVICE, TS-3620/GVS-5 (NSN 5860-01-052-9477)
TM-11-6625-2684-12HR
TM-11-6625-2684-20P
TM-11-6625-2684-30P

Range Finders -
PAS-6 - Varo Metascope Model 9902E
EOG - Electro Optical Gadgets