Altimeter

QNH

QNH is a sea-level pressure setting. With an appropriate local QNH, the altimeter indicates altitude above mean sea level.

QFE

QFE is a station/reference-location pressure. It is useful when you want altitude relative to a particular reference level rather than mean sea level.

QNE

QNE uses the standard pressure setting of 1013.25 hPa / 29.92 inHg. In Marine Barometer it is an explicit fixed standard-pressure mode.

Linked and Unlinked

LINKED lets Marine Barometer manage the effective altimeter reference from the selected mode and available reference information. UNLINKED lets you control the setting manually. QNE is fixed by definition and is used unlinked.

Changing the altimeter setting changes the altimeter indication; it should not change the Barometer pressure reading.