Radar Observer · Controls — VRM and EBL
The variable range marker (VRM) and electronic bearing line (EBL) are used to:
- AStabilize the picture to north
- BIncrease the transmitter power
- CRemove sea clutter
- DMeasure precise range and bearing to a target without the parallax error of the fixed range rings or a mechanical cursor✓ Correct
Explanation
The VRM is an adjustable ring set tangent to a target to read its exact range; the EBL is a rotatable line laid through a target to read its bearing. Both are read electronically, avoiding the parallax and interpolation errors of estimating between fixed range rings or using a parallax-prone cursor.
Authority: Bowditch (Pub. No. 9), Radar Controls
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Related Radar Observer questions
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- Controls — EBL
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