the dark room. Gradually raise the level of illumination to where
the pattern becomes indiscernible. Place a fixed stop having an
aperture of onehalf inch over the objective window and observe
that the reticle pattern is again clearly discernible by means of
the self-illumination to 10 foot candles, remove the fixed stop,
and observe the reticle pattern.
4.8.32 Counter illumination. Follow 4.8.22 to acquire
proper dark adaption. The unaided eye shall be capable of
determining the counter numerals and numeral alignment at various
light levels that simulate dusk into darkness.
contamination. Contamination test
shall be performed by wiping the telescope with filter paper
moistened in distilled water. The wiping shall be performed with
moderate finger pressure. The damp filter paper shall be placed
in a container with the proper portion of scintillation liquid.
The scintillating system used to measure contamination must be
calibrated and be within 10% of the known standard value when
counted to a total of 2000 disintegrations. The actual test for
determining contamination is performed by placing the container
into the scintillation system. The measured contamination shall
be within the limits specified in 3.13.3.
4.8.25 Cleanliness. The unit under test shall be subjected
to the test procedures outlined in MIL-O-13830 for conformance to
the requirements outlined in 3.9.1.
4.9.1 Storage and operating temperatures. The telescope
shall be subjected to one cycle of temperature variations in
accordance with Table III. Upon completion of Sequence 1 and 4
soak periods (Storage) , the telescope shall be visually and
tactually examined to insure conformance with the requirements of
3.7.1. Upon completion of Sequence 2 and 4 soak periods
(Operating), the telescope shall be visually and tactually
examined to assure conformance with requirements of 3.12.
Following completion of Sequence 3 and 5 soak periods (Room
temperature) the telescope shall meet all the requirements of
3.7.6 through 3.13.1.
TABLE III. Temperature Cycle
+160°F(71°C) 4 hrs
+150°F(65°C) 2 hrs
+60°F to +90°F 3 hrs
(+16°C to 32°C)
-50°F(-46°C) 4 hrs -50°F(-46°C) 4 hrs*