USSR Survey Heliograph
Product details: USSR Survey Heliograph | | Targets and prisms | |
The heliograph is used to create a long distance signal during day times. Using the heliostat a very bright target can be created. It needs to be targeted towards the theodolite requireing an assistant to be in place. This heliograph is mounted on a wooden board which can be set up and adjusted for heigh. The mirror can be rotated and via the small hole in the mirror the bundle of light can be sighted on the crosshairs at the end of the board. Aligning the two with the theodolite (far away) allows a beam of light to be send in that direction. Using the red filter it can even be coloured.
It could have been that there was a second box with a shutter originally, however I do not have that and it would not be necessary for survey work either.
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