How do you do a VHF radio check properly?
I've just fitted a new Standard Horizon VHF and want to make sure it's transmitting and receiving properly before heading offshore. What's the correct etiquette and channel for a radio check in UK waters?
Answer
Never use Channel 16 for a routine radio check; instead, call a local marina, a fellow boater on an inter-ship channel, or the National Coastwatch Institution (NCI) on Channel 65. State your vessel's name, your location, and ask for a brief report on your signal strength and clarity.
Choosing the Right Channel
The days of calling HM Coastguard on Channel 16 for a radio check are long gone. Channel 16 is strictly for distress, urgency, and initial calling. Cluttering it with radio checks earns a stern rebuke. In UK waters, your best option is the National Coastwatch Institution (NCI). They maintain a listening watch on Channel 65 and provide accurate radio checks. Check their local operating hours before transmitting.
Inside a marina or harbour, call the berthing master on Channel 80 or the designated port control channel. Marinas are exceptionally busy on summer mornings and weekends, so time your call for a quiet period. Alternatively, arrange a ship-to-ship check with a friend on a working channel like Channel 72 or 77. When testing a newly installed fixed VHF, such as a Standard Horizon GX1400 or an Icom IC-M330, get a response from a station at least five miles away. This proves your masthead antenna performs under load.
The Standard Voice Procedure
Before touching the transmit button, turn your squelch down until you hear white noise. Dial it back up just until the noise breaks. Ensure your radio is set to high power (25W) for a distant station, or low power (1W) when calling a marina office across the pontoon. High power over a short distance causes distortion.
The script follows standard marine radio protocol. Press the Push-To-Talk (PTT) button, pause for one second so the first syllable transmits clearly, and say:
- "National Coastwatch St Alban's Head, National Coastwatch St Alban's Head. This is motor cruiser Sea Spirit, Sea Spirit. Request radio check, over."
When the station acknowledges your call, they will give you a readability report. Finish the exchange with:
- "Many thanks for the check, Sea Spirit listening on Channel 65, out."
Decoding the Response
A proper radio check response uses the readability scale from 1 to 5. A report of "Readability 5" means your signal is loud and clear. "Readability 3" means you are readable but with difficulty, perhaps accompanied by static or background hiss. A simple "Loud and clear" is perfectly acceptable for everyday use.