Does the compass card of a Radio Magnetic Indicator (RMI) point to true north or magnetic north ?

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    $\begingroup$ RMI (radio magnetic indicator) displays a magnetic direction, like the compass and a lot of things in aviation The RMI magnetic bearing leads to the navaid which is usually what the pilot wants. Navigating using magnetic north is also done by a walker with a compass. The magnetic declination describes how magnetic north and true north differ. $\endgroup$ – mins Aug 13 '16 at 11:10
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    $\begingroup$ I removed your second question about using true vs magnetic because it looks like it's been answered here. If that answer doesn't help you, then you can just edit this question again, or ask a new question. $\endgroup$ – Pondlife Aug 13 '16 at 14:24

In a typical installation, the compass card of an RMI indicates magnetic north.

While it is possible to switch that reference on an EFIS display to true north by applying the local variation, that is not the common practice. If you see a "steam gauge" RMI (i.e. not a digital display, but a mechanical compass card) in a panel, chances are excellent that the compass card is slaved to the same heading source as everything else -- magnetic north. In the exception cases, that source can be switched between true & magnetic, but that's uncommon.

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