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Docs Frequencies & Regulations PMR446 Deep Dive

PMR446 Deep Dive

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The license-free European radio service, its 16 channels, the 500 mW ERP limit, and how to configure the beacon for it.

PMR446 Deep Dive

PMR446 is the European license-free radio service at 446 MHz. It is the most legally straightforward band for a European beacon user.

The basics

  • Frequency: 446.0-446.2 MHz (16 channels, 12.5 kHz spacing).
  • Power: max 500 mW ERP.
  • License: none required in most European countries (CEPT countries).
  • Antenna: the rules historically required an integral (non-removable) antenna for PMR446 equipment. A removable SMA antenna is not compliant with the original spec, which is a real consideration for a beacon with an external antenna.

The 16 channels

ChMHzChMHz
1446.006259446.08125
2446.0187510446.09375
3446.0312511446.10625
4446.0437512446.11875
5446.0562513446.13125
6446.0687514446.14375
7446.0187515446.15625
8446.0437516446.16875

Configuring the beacon for PMR446

  1. Set the frequency to a PMR446 channel (e.g. 446.00625 MHz).
  2. Set TX power to 500 mW ERP or less. The beacon’s +17 dBm (50 mW) is comfortably under the limit.
  3. Keep the antenna compliant with local rules; a quarter-wave whip on 446 MHz is about 16.8 cm.

Why PMR446 matters for the beacon

  • It is the legal path for unlicensed European use.
  • Any PMR446 walkie-talkie can hear the beacon’s CW if it has an SSB/CW-capable mode, or via an SDR.
  • The 500 mW ERP ceiling still gives useful range: a few kilometers line-of-sight.

The honest caveats

  • A beacon transmitting Morse on a PMR446 channel is a legitimate use of the service for distress signaling, but check the specific national rules about non-voice emissions.
  • The integral-antenna rule conflicts with the E22’s SMA; some operators interpret emergency use as overriding this. Know your local position.

Also see

The frequency planning examples page has a full EU configuration walkthrough with a PMR446-compliant setup.