TM 9-1556
1-2
INTRODUCTION
SCOPE.
a. This manual is published for the information and guidance o f
ordnance personnel. It contains detailed instructions for inspection,
d i s a s s e m b l y , reassembly, maintenance, and repair of the Observation
T e l e s c o p e s M48 and M49. These instructions are supplementary to
those in Field and Technical Manuals prepared for this using arms.
Additional descriptive matter and illustrations are included to aid
in providing a more complete working knowledge of the materiel.
2.
CHARACTERISTICS.
a.
The telescopes discussed herein are used for observaaton by
the cavalry and infantry. Their chief purpose is to assist in observing
the effectiveness of artillery fire.
b. Both Telescopes M48 and M49 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.
Figure 1-Observation Telescope M48