Dublin Core
Identifier
1555
Title
Videograph B Fog Signal Detector
Description
As the Coast Guard automated their lighthouses and removed Keepers who visually sighted fog and turned on the signal, a means to detect fog electronically was invented. This device became the standard sensor used by the US Coast Guard to detect fog and turn on the signal.
The detector consists of two parts, a projector, and a receiver. The projector sends out stereo-type flashes of light which hit air particles of fog, which are retracted back to the receiver as "back scattered light." The receiver's threshold is adjusted to turn on the fog signal at a specified density level.
This device was located in the electrical/battery room adjoining the light tower here at Beavertail.
The detector consists of two parts, a projector, and a receiver. The projector sends out stereo-type flashes of light which hit air particles of fog, which are retracted back to the receiver as "back scattered light." The receiver's threshold is adjusted to turn on the fog signal at a specified density level.
This device was located in the electrical/battery room adjoining the light tower here at Beavertail.
Physical Object Item Type Metadata
Storage Location
Oil House