https://www.cnbc.com/2017/08/17/here-is-where-cellular-carriers-are-increasing-coverage-for-the-solar-eclipse.html >The four largest U.S. cellphone carriers are deploying portable towers to step up coverage for the massive crowds expected to gather during Monday's solar eclipse. >Verizon, AT&T, Sprint and T-Mobile will be sending mobile cellphone units to towns, many of them in rural areas, where they expect networks to be at greatest risk of strain.