Product Overview: Azimuth Test Fixture
NSN: 4931-00-769-1596
P/N: 7691596

General Description The azimuth test fixture consists of a base, azimuth ring, vernier scale, adapter support plate, and column. It uses various mounting adapters to accomodate different fire control instruments and uses a projector collimator for a test target. The base is cast iron and has three leveling screws. It mounts and supports the other components of the fixture. The azimuth ring is precisely machined and graduated into 6400 mils by six hundred forty engraved lines, each of which represents 10 mils. The ring can be set at any position and locked in place with a clamping arm which is mounted under the base. A spring loaded plunger and adjustment screw provides for fine adjustment of the azimuth ring. Shown with optional "Seiler Digital" system

3. The vernier scale mounts on the base in a machined track. It has an engraved scale consisting of fifty one graduations. Each graduation represents 0.2 mil. Every tenth line is numbered progressively by increments of two from 0 to 10. It is possible to estimate readings as small as 0.1 on the vernier scale.
4. The column clamps to the base and supports the projector collimator.
5. The adapter support plate is fastened to the spindle of the azimuth ring, concentric to the ring. A machined surface perpendicular to the axis of the spindle, provides the mounting surface for the test fixture adapters. Three cam-head screws in the plate permits easy clamping of the adapters on this surface.

Application
The azimuth test fixture is used for adjusting and inspecting panoramic and azimuth indicating, fire control instruments such as the M-2 Aiming Circle, M117 Panoramic Telescope and the M12A7 Panoramic Telescope. Parameters that can be checked with this test fixture are: backlash in azimuth and elevation gears, level travel, azimuth and micrometer scale accuracy, and counter accuracy.