I don't have a 'traveling' advice, but am in an LDR. Don't talk on the phone daily. Which works well, for both, what's brought forth to table. For instance, talked yesterday, probably won't tonight, may tomorrow or Wednesday, however. Lots of texting involved, use a couples website, where we can post private notes, links, cutesy stuff.
I feel, it's OK, for you to say, you'd really like to speak, at least once during this vacation, over the phone. There is a certain connection to hearing one another's voice. It's OK, to say, that though you recognize you both have varying needs in this department, a conscious effort to meet you half-way/part-way/some of the way would go a long way to leaving you feeling valued.