Defect Detector with Audio
The photos are of the defect detector on the FEC mainline in S. Lucie County, Fl. at Walton Road, north of Jensen beach.
The audio was recorded online listening to the Broadcastify Folkston, Ga. area feed. The detector is on the dual CSX mainline mile A610.6 between Boulogne and Callahan, Fl. Listen to the end.
More information at the Trains Magazine website. Always a good source.
Several other videos on YouTube.
EDIT March 20, 2016 to add some still photos
Hotbox or Hot Bearing Detector
Dragging Equipment Detector
Lasers shine down on each side of the passing train. Anything that cuts through the beam will be counted as a defect.
Control box and VHF Antenna
Overview of hotbox and dragging equipment detectors with one leg of bridge that holds laser detectors.