Description:
- Object ID: ALSA 2006.24.01
- Made by: AGA, Sweden
- Model: 6
- Serial Number: 6571
- Date Made: Circa 1964.
- Approximate size: 53.3 cm height with scope in vertical position, 35.6 cm width, 21.6 cm depth
- Accessories: The instrument comes with a tan colored fiberglass backpack carrying case. The case contains a calibration table and two cables one of which is a battery cable.
- Condition: Good
Commentary:
The Geodimeter applies the speed of light to measure distances. By measuring the time required for a beam of light to travel to a reflective prism and back the distance between the two points could be accurately determined.
The Model 6 has a range of 1-2 miles in daylight and 10 miles in darkness. It had a standard accuracy of 5mm +/- 1mm/km. Without a case or tripod it weighed only 35 pounds. It cost approximately $10,000 and could be powered with a 12 volt car battery.
The Geodimeter (acronym for geodetic distance meter) was the invention of the Swedish Physicist Dr. Erik Bergstrand who designed it. He applied it to the measurement of the speed of light over measured distances in 1947. His original geodimeter, introduced in 1949, weighed more than 100 kilograms and was the first EDM instrument ever made.
Source of Object: Donated by J.B. Underwood & Associates Ltd.
Notes: The Society has only one in their collection.
References:
- Visit article Measuring by Speed of Light – The Geodimeter for additional information.
- R. Smith “The History of Geodimeter, 1947-1997, http://www.geotronics.it/public/geodimeter_story.pdf
- James Smith Murphy, Electronics Based Innovation in a Niche Market: Distances Measured By The Speed Of Light, Thesis submitted to the Graduate Faculty of North Carolina State University. 2004: https://repository.lib.ncsu.edu/bitstream/handle/1840.16/961/etd.pdf?sequence=1
- 100 Years of Geodetic Surveys in Canada. https://www.nrcan.gc.ca/maps-tools-publications/maps/100-years-geodetic-surveys-canada/9110
- Spectra Geospatial, About Us: https://spectrageospatial.com/about-us/
Description by: Ed Titanich, October 3, 2024.