Module 2 - VHF Radio Basics
Controls You Must Know Without Hunting
What you will learn
Locate and operate the essential controls on the vessel's actual fixed and handheld radios before stress makes a menu search unsafe.
SRC knowledge must transfer to the set in front of you. Know how to power it, select a channel, set volume and squelch, choose transmit power, operate PTT and return to the required watch channel.
The CEPT SRC syllabus explicitly includes channel selection, dual-watch or scanning facilities, power connection, on/off, PTT, high/low output, volume, squelch and dimmer controls. Layouts differ: a function that has a labelled knob on one set may sit behind a soft key or menu on another.
Familiarisation should be deliberate and non-transmitting. Use the manual, simulator, training mode or a powered-off walk-through; do not press the distress control or make an unnecessary live transmission to discover what a button does.
A helm briefing should identify the channel being monitored, the way back to Channel 16, the vessel call sign and MMSI card, the location of the handheld, and the person controlling routine radio use. Familiarity reduces delay, but it does not replace correct priority or procedure.
Run a two-minute control handover
A relief skipper joins a charter yacht whose VHF menu is different from the set they normally use.
1. Locate
Point out power, channel selection, volume, squelch, low/high power, PTT, Channel 16 return and display dimmer.
2. Confirm state
Read the displayed channel, power level, watch facility and position status rather than assuming the last crew left them correctly.
3. Rehearse safely
Talk through a routine call and a return to the watch channel without creating live traffic.
Sense check: If a crew member cannot return the radio to receive mode after a practice explanation, PTT operation is not yet secure.
Common mistake or limitation
- Assuming every radio uses the same button names and menu path.
- Testing unfamiliar controls with a live distress alert or unnecessary transmission.
- Briefing only the channel number and omitting radio identity, PTT release and the watch-channel return.
Recap
- Learn the installed radio, not only generic control names.
- Use the manual or non-transmitting practice for unfamiliar controls.
- Confirm the displayed state at handover.
- Keep vessel identity and emergency information beside the radio.
Optional quick check
Section 4 of 9
On an unfamiliar radio, what is the safest way to learn the distress-control cover and cancellation route?
Sources and factual review
Reviewed 20 August 2026 - Compass Revision editorial review.
Continue studying VHF Radio Basics
This public lesson is part of Revision Module 2. Full revision access adds the guided Learn, Practise and Test flow, flashcards and revision progress.