My local radio group has a formal agreement to provide emergency communications for our County Health Dept.
We have conducted drills using our repeaters to cover various locations in our County.
Yesterday another operator and I conducted a test using 2 meter PSK31.
He was at a fixed location and I was mobile. I "worked" him from 4 different locations at a power ouput of only 1/2 watt. The antenna used was a 1/4 wave mag mount on the roof of our vehicle.
The test shows that digital communications, using very low power and compromise antennas are a reliable means to pass information.
Conservation of available power is another reason to use low power methods as well.
Overall a very successful test!