SINS and the Coast Guard Navigation Standards

What does this mean: it means that an RD-30 alarm uses the RD-30 offset and the Radar/Video Plotter alarm uses the Radar/Video Plotter offset. The Defender Class Bravo (RB-S) is set to read "True Bottom" with a -1 ft offset. The 41’UTB has a -2ft offset. RD-30 Depth Alarm … ................
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