Model DKM3-A
Serial No 188524
The DKM3-A is a variant of the Double Circle Triangulation Theodolite DKM3, the principal changes being those necessary to facilitate the addition of an astronomic micrometer accuracy: The results indicate that the DKM3-A is capable of producing first-order latitude and longitude determinations.
FIELD CHARACTERISTICS: The DKM3-A is an excellent field instrument from the viewpoints of portability, versatility, and observer convenience. The DKM-3 has already proven that the basic mechanical and optical components are sound, and it is likely that the DKM3-A will prove adequate in these respects also. The additions of the astronomic micrometer, weighted striding level, and double Horrebow level add considerably to the weight that the vertical axis system must support, and its effect on the life of the system could prove significant. The DKM3-A appears to have all the necessary ingredients to make it a valuable addition to the geodesists' array of tools. (ref. William E. Carter, Master thesis, "A field evaluation of DKM3-A," Colombus University, Ohio State, 1965).
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