Circuitron 800-5521 BD-1HD Optical Detector Ballast - Medium 5 - Clear Styrene -

5 - Clear Styrene - 5" x 5" (12

make that one worker

easy-to-read display

3 Motorcycle Body

Circuitron 800-5521 BD-1HD Optical Detector Ballast - Medium 5 - Clear Styrene -Circuitron 800 5521 BD 1HD Optical Detector The Circuitron BD 1 is an advanced, integrated circuit design Block Occupancy Detector utilizing our proven Opto Electronic design which provides positive indication when ever a block section of a layout is occupied by any piece of rolling stock. The BD 1HD is identical to the BD 1 but includes heavy duty output transistors to power lamps in large scale signals. Each output on the BD 1HD can control 500 ma.