The honest range table (PMR446, 500 mW)
| Environment | Realistic range | What's going on |
|---|---|---|
| Dense town centre | 300 m – 1 km | Buildings absorb and scatter the signal |
| Suburbs / villages | 1 – 2 km | Fewer, lower obstructions |
| Open countryside | 2 – 5 km | Terrain is now the limit — one hill ends the conversation |
| Hilltop to hilltop | 10 km + | True line of sight: the box-figure scenario |
| Inside a large building | 2 – 6 floors / a few hundred metres | Steel and concrete are the hardest test of all |
| Ship-to-shore / water | Good over open water | But use proper marine VHF for safety at sea — different rules |
Why the box number is "true" and useless
UHF signals at 446 MHz travel essentially by line of sight. Give two radios an unobstructed path — up a mountain, across a calm bay — and 500 mW genuinely carries 10 km or more. Put a supermarket between them and the same radios struggle at 400 metres. The marketing figure reports the first scenario; your life happens in the second. As a rule of thumb, divide the box claim by ten for towns, by three or four for open country — and you'll rarely be disappointed.
What genuinely helps (and what doesn't)
Helps: height
The single biggest lever. First floor beats ground floor; a supervisor on a mezzanine covers a warehouse a ground-level radio can't.
Helps: fresh batteries
Transmit power sags with the cells. Half the "range got worse" complaints in the trade are tired NiMH packs.
Helps: outdoors
One exterior wall can cost more signal than half a kilometre of open air. Step outside, watch bars return.
Doesn't: "high-gain" claims on fixed-antenna radios
PMR446 antennas are fixed by law and the power is capped — there's no accessory that changes the physics. Anything promising otherwise is either useless or illegal.
When you need more than the physics allows
Once you've gained height, gone digital and still can't cover the ground, you've hit the standard's ceiling and the fix is a different system, not a better PMR446 radio. Three upgrade paths, in order of ambition: a licensed radio (more power — roughly doubles real range); a licensed system with a repeater sited high (site-wide coverage for difficult buildings); or a network radio, which sidesteps radio range altogether by using the mobile networks — the practical answer when "range" means different postcodes rather than a bigger yard.
Quick answers
How far in a town?
PMR446: 500 m to 2 km, dictated by buildings. Large steel/concrete structures can cut that to a few hundred metres.
Why does the box say 10 km?
It's the hilltop-to-hilltop line-of-sight figure. Divide by ten for urban reality.
How do I increase range?
Height, fresh batteries, get outdoors. Beyond that, change system: licensed power, a repeater, or network radio — which has no range limit at all.