Product Overview: M49 Observation Telescope W/E
NSN: 6650-00-678-5627
P/N: 6785630

Characteristics
The telescopes discussed herein are used for observation. Their chief purpose is to assist in observing the effectiveness of artillery fire.

The M48 and M49 Observation Telescopes are basically the same. Each is an erect-image instrument, the image being erected by means of two porro prisms and magnified by the lenses in the eyepiece. Both telescopes are the "prism-offset" type and are tubular in shape. The arrangement of the optical elements is the same in both instruments.

The equipment for each telescope includes a carrying case and tripod with carrying case. Telescope M48 uses Carrying Case M26, and Tripod M14 with Carrying Case M31. Telescope M49 uses Carrying Case M27, and Tripod M15 with Carrying Case M42.

Differences Between Models
Despite their similarity in many respects, there are some differences between these models, as shown by the following comparative specifications.

Description
Observation Telescope M48
a. Observation Telescope M48 is a 19.6 power telescope having a field of view of 2 degrees 8 minutes and an exit pupil diameter of 0.100 inch. The image is erected by a porro prism system. The over-all length of the telescope with the sunshade closed is approximately 13.5 inches.

b. The major units of Observation Telescope M48 are the objective assembly, body tube, prism housing assembly, and focusing mechanism with eyepiece assembly.

c. The front of the telescope has a sliding sunshade which can be extended approximately 2 inches as the need requires.

d. The telescope is furnished with an objective cover and eyepiece cap. These are screwed into place to protect the lenses when the telescope is not in use.

e. The telescope is focused by pushing or pulling the eyepiece in or out until an approximate focus is reached, and then turning the knurled focusing sleeve to obtain exact focus. This arrangement is made possible by a spring-loaded ball which either rides over the threads of the focusing nut, when the eyepiece is pushed or pulled, or engages the threads when the eyepiece is turned.

Observation Telescope M49
a. Observation Telescope M49 is a 20-power telescope having a field of view of 2 degrees 12 minutes and an exit pupil diameter of 0.108 inch. The image is erected by a porro prism system. The overall length of the telescope is approximately 14.5 inches.

b. The major units of Observation Telescope M49 are the objective assembly, the body tube, the prism housing assembly, and the focusing mechanism with eyepiece assembly.

c. Observation Telescope M49 does not have an adjustable sunshade. Instead, the front end of the body tube extends approximately three-quarters of an inch beyond the objective, thereby providing a permanent sunshade.

d. The telescope is furnished with an objective cover and an eyepiece cap. These are screwed into place to protect the lenses when the telescope is not in use.

e. The telescope is focused by turning the knurled focusing sleeve.

Accessories
a. Accessories for Observation Telescopes M48 and M49 include a carrying case for each telescope, a tripod for each telescope, and a carrying case for each tripod.

Tripod M14 (For Telescope M48)
The M14 Tripod provides a rest for the Telescope M48 and steadies it when in use. The telescope rests in the cradle of the tripod and held securely. A socket and ball connection between the tripod cradle and the leg assembly permits movement of the telescope. A clamping nut holds the telescope at any required angle. With the folding legs of the tripod fully extended, the eyepiece of the mounted telescope stands approximately 11 inches above the surface upon which the tripod rests. The telescope can be raised or lowered, and can be held at any position by tightening the clamping thumbscrew. The tripod folds into a compact unit which fits readily into the carrying case. The principal assemblies of the Tripod M14 are the cradle assembly and the leg assembly.

Tripod M15 (For Telescope M49)
The M15 Tripod provides a rest for the Telescope M49 and steadies it when in use. The telescope rests in the cradle and is held in place by a clamp assembly. With the folding legs of the tripod fully extended, the eyepiece of the telescope is approximately 11 inches above the surface upon which the tripod rests. With this tripod, the telescope can be swung around to any desired position. An elevating screw is also provided for elevating or depressing the forward end of the telescope as necessity requires. The main assemblies of Tripod M15 are the cradle assembly and the leg assembly. These two assemblies are joined by means of the cradle support shaft which extends through the collar in the leg assembly. The Tripod M15 folds into a compact unit and fits into its carrying case for ease and convenience in transportation.