Emergency Frequencies
Edit on GitHubThe frequencies rescue services and amateurs monitor, and where a beacon transmission is most likely to be heard.
Emergency Frequencies
A beacon is only useful if someone is listening. This page covers the frequencies where that is most likely.
What a beacon can realistically do
The beacon transmits on your configured frequencies. For it to help, a receiver must be tuned to one of them. The two realistic listeners are:
- A rescue team carrying an SDR or scanner that they tune to the known beacon frequency.
- Amateur operators monitoring 70 cm simplex or repeater frequencies who hear your CW.
Frequencies worth configuring
| Frequency | Context |
|---|---|
| 433.500 MHz | Common European 70 cm simplex frequency, widely monitored |
| 433.050 MHz | Edge of the ISM allocation, low chance of interference |
| 446.00625 MHz | PMR446 channel 1 (license-free band) |
| 434.000 MHz | Common ISM calling frequency in some regions |
| Your local repeater output | If licensed, transmitting on a repeater output relays your signal |
The coordinated approach
The most reliable scenario: a team agrees on a frequency beforehand. The beacon is configured for it, and the team’s receiver is tuned to it. This is the “emergency communications plan” page’s core idea.
What not to do
- Do not transmit on frequencies used by air traffic, emergency services, or maritime distress unless you are in a genuine emergency.
- Do not hop onto repeater inputs without a license.
- Do not assume “somebody monitors 433.5” - in a quiet area, nobody does. The plan matters more than the frequency.
The honest answer
There is no universally monitored “beacon frequency”. The value of the beacon comes from the search team knowing where to listen. Frequency selection is coordination, not radio magic.