Sensor incorporating a circular spirit level, electrical lamp and two pairs of photocells, provides an electrical indication of flat surface level deviation.
Sensitive level sensor made with spirit level, gives electrical output
1965-03-01
Miscellaneous
No indication
English
Plane-level gives electrical output.
NTRS | 1965
|Understanding the process that gives rise to household car ownership level changes
Online Contents | 2016
|Sensitive clinometer and level
Engineering Index Backfile | 1945
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