How do I perform a proper VHF radio check from my boat?
I've got a fixed VHF at the chart table and a handheld in the cockpit. Before leaving the marina, how should I check that they're transmitting properly, which channel should I use, and what exactly should I say?
Answer
Arrange a short call with a nearby boat or marina on an appropriate working channel, ask for a radio check, and listen for a report on signal strength and speech clarity. Check the channel, volume, squelch and power supply first, as a wrong setting can make a working radio seem faulty.
Set up before transmitting
Test the radio as you normally use it: the fixed set with its installed aerial and microphone, or the handheld from the cockpit. Testing a handheld inside the cabin can give a misleading impression of its range.
- Power: switch on the fixed radio's supply and charge the handheld. A lit display does not prove that the battery or wiring can support transmission.
- Channel: select the agreed channel and correct regional channel group, usually INT or International in UK and European waters.
- Volume: turn it high enough to hear speech over the engine and wind.
- Squelch: turn SQL down until you hear background hiss, then increase it just until the hiss stops. Too much squelch cuts out weaker replies.
- Transmit power: start on LOW for a nearby station. Fixed sets commonly offer 1 W and 25 W; handheld maximum output varies by model, commonly around 5 to 6 W.
Connect the aerial before transmitting. Keep people clear of it by the separation distance specified in the radio's installation manual.
Choose your station and channel
Arrange the check with a neighbouring boat whose skipper has agreed to listen, or a marina that accepts checks on its published working channel. Use a channel authorised for the purpose locally; marina, port and intership channel arrangements vary between countries and harbours.
Keep routine checks off Channel 16 wherever a suitable working channel is available. Channel 16 is the international distress, safety and calling channel, and prolonged testing takes up valuable airtime. Do not assume the coastguard provides routine checks. If you specifically need to contact it, follow its locally published arrangements.
Never make a voice check on Channel 70. It is reserved for digital selective calling, or DSC. The red DISTRESS button is not a test button; any DSC test must use the set's dedicated test-call function and an appropriate receiving station.
Make a short call
Listen first. If someone is speaking, wait until the exchange has finished. Hold the microphone roughly 5 cm from your mouth, or follow its manual. Shelter it from wind without covering the microphone opening.