Except for flying an approach at the alternate:

Nope. Except for determining a legal alternate. Once you are in the
air, if you need to go to =an= alternate, it doesn't have to be your
filed one, and even if you decide to go to your filed alternate, there
are no special GPS rules. You can use the approach-certified GPS as a
substitute for NDB and DME, except for an NDB approach, just like your
original destination.

Jose
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