If you use Calibre it is possible to recalibrate the base font size to make it larger. This requires a reflowable format (like ePub, so use Calibre to convert PDF to ePub if necessary), and I don't know for sure that this has the desired effect on a Nook - but it should.
Note that Calibre only works with DRM-free ebooks, so you first need to strip DRM, if any. Apprentice Alf's Blog has a good summary of DRM stripping tools and issues.
|