Section XII. HORIZONTAL CIRCLE ILLUMINATION PRISM AND HOUSING COVER,
HORIZONTAL CIRCLE PRISM CARRIER, AND ILLUMINATION CABLE CONNECTOR
109. General
b. Disassembly.
Refer to figure 59 and
The horizontal circle housing cover encloses the bottom
disassemble the horizontal circle housing cover and
of the horizontal circle housing and serves as a mount
horizontal circle illumination prism.
for the horizontal circle illumination prism.
The
c. Cleaning, Inspection, and Repair.
illumination prism directs light to the horizontal circle
(1) Clean all metal parts with an approved
prisms. The horizontal circle prisms transmit the circle
cleaning solvent and dry thoroughly.
image to the microscope window and also provides light
(2) Clean the prism and lens with a lens cloth
for reading the micrometer circle. The cable connector
or lens tissue.
provides a means for connecting the electrical cable
(3) Inspect the horizontal circle housing cover
from the contact ring to the socket.
for dents, cracks, or other defects.
Inspect all threaded parts for damaged or
110.
Horizontal Circle Housing Cover and
worn threads.
Horizontal Circle Illumination Prism
(4) Inspect the prism and lens for cracks,
a. Removal.
chips, etchings, and other damage.
(1) Remove the leveling screws (par. 117).
(5) Replace all damaged or worn parts.
(2) Refer to figure 58 and remove the
d. Reassembly. Refer to figure 59 and reassemble
horizontal circle housing cover and
the horizontal circle housing cover and horizontal circle
horizontal circle illumination prism.
illumination prism.
e. Installation.
(1) Refer to figure 58 and install the
horizontal circle housing cover.
(2) Install the leveling screws (par. 117).
111. Horizontal Circle Prism Carrier
a. Removal.
(1) Remove the horizontal circle housing
cover (par. 110).
(2) Refer to figure 60 and remove the
horizontal circle prism carrier.
b. Disassembly.
Refer to figure 61 and
disassemble the horizontal circle prism carrier.
c. Cleaning, Inspection, and Repair.
(1) Clean all metal parts with an approved
cleaning solvent and dry thoroughly.
(2) Clean the lenses and prisms with a lens
cloth or lens tissue. Inspect the lenses
and prisms for cracks, chips, etchings,
and other damage.
(3) Inspect all lens, mounts, and the prism
carrier for bends, wear, and other
damage.
Figure 58. Horizontal circle housing cover and
(4) Clean all threaded surfaces with a brush
horizontal circle illumination prism, removal and
dipped in an approved cleaning solvent.
installation.
73
AGO 5078A
