“You—complete—arse—Ronald—Weasley! You—crawl—back—here—after—weeks—and—weeks—oh, where’s my wand?”
-- Hermione Granger, not pleased to see Ron (DH19)
Ron used the Deluminator to magically travel to where Harry and Hermione were camping once they said his name aloud. Ron arrived just in time to rescue Harry from drowning in the icy pond where the Sword of Gryffindor had been placed, and then used the Sword to destroy the locket horcrux. Despite these heroics, Hermione was, well, somewhat cool toward Ron when he and Harry went back to the tent.
One possible influence on the whole camping portion of DH, including the trio's interactions and the influence of the locket, is the 1999 horror film The Blair Witch Project, which is about three young people who spend night after night in a tent in the woods while trying to reach safety and having extremely intense interpersonal conflicts - all while under the shadow of (what can at least be interpreted as) an evil magical force or presence of some sort. -BB