How the estimator works
The numbers come from our radio range model. It uses the international rules for short outdoor radio paths, the power limit of each radio and the sensitivity from its datasheet.12 The first number is the distance where nearly every call gets through. The second is where about half of them do.
Both people hold the radio at head height. That is why the numbers are far below the "up to 10 km" on the box. Makers quote the best case: from one hill to another, with nothing in between.3 The Latvian spectrum office gives the same picture for PMR446. It expects a few hundred meters in a city and up to a few kilometers in the countryside.4
Sources
- PMR446 guide · Elektroniskie sakari
