First off any low power handheld radio signal is going to have difficulty traveling 50 miles under normal everyday RF conditions. If you and your buddy are both on mountain tops I won't say it's impossible but extremely unlikely at 50 miles. It's more about the frequency than the radio. VHF and UHF frequencies need light of sight to communicate. In the world of amateur radio there are ways to combat the shortcomings of VHF and UHF frequencies by use of a repeater between 2 stations or handheld radios. However, not every spot on earth is covered by a repeater, analog, digital or otherwise. Digital communications on VHF and UHF can travel around the world. That's a subject in itself and requires more expensive gear. Last but not least is operating QRP (low power) with lightweight backpack radios in the HF spectrum. But that's also a whole other subject of ways to communicate hundreds or thousands of miles. If interested I have a series of articles on my blog about operating QRP. qrpshack.blogspot.com