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ARINC 424 contains 2 dedicated record types for NDB. One for NDB NAVAID (DB) containing all LF and MF NDBs and selected Marine Beacons defined in the enroute structure and one for the Terminal NDB (PN). Both record types contain the data field NAVAID Class (CLASS), that, inter alia, is used to distinguish between NDB, Locator and Marine Beacon (additional classification elements are part of this data field which do not fully coincide with AIXM 5 concept, e.g. codes for high powerd NDB , low powered NDB, etc.).
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NDB Designator & Name
In general, enroute NDB will carry a three letter character identifier. Locator may have 2 or one character.
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In case a NDB (Locator) is collocated with a Marker and the position of the NDB is different from the position of the Marker, some restrictions have to taken into account (see coding rules for Marker Beacon).
For mor edetails see topic Navaid Position & Elevation.
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