Should I use a handheld or the fixed VHF set in a marina?

Near a harbour, use the fixed (mounted) set on low power in preference to a handheld. Marine VHF is line-of-sight: the fixed set transmits through the masthead antenna, which is typically 12-18 m up and clears the breakwater and the forest of other masts around you. A handheld held at deck level is low down and easily blocked by the mole and surrounding hulls and masts, so even a "stronger" handheld often gets through worse than the fixed set on 1 watt.

Why use 1 watt instead of 25 watts near the harbour?

At close range you do not need the extra power, and low power is good manners: 25 watts blasted across a packed marina can overload and desensitise nearby receivers and reaches far beyond the boats you are actually talking to. On 1 watt the masthead antenna still has the height to clear the breakwater and reach the marina office or a nearby boat cleanly. Marine VHF radios have a dedicated 1 W / 25 W power switch for exactly this reason — drop to 1 W in and around the harbour, use 25 W offshore.

Does a breakwater or mole block VHF radio?

It can block a low antenna. VHF travels in a near-straight line and does not bend around solid obstructions well, so a handheld held near the water behind a stone mole may be shadowed from the station on the other side. A masthead antenna sits above the mole, keeps line-of-sight to the far station, and gets the signal out even on low power. This is why height, not power, is usually the deciding factor close to shore.

Is antenna height or transmit power more important on VHF?

Height, in most situations. Because VHF is line-of-sight, your range is limited by how far the horizon is from your antenna, not by how many watts you push. Raising the antenna extends that horizon far more effectively than increasing power. A masthead antenna on 1 watt will often outperform a deck-level handheld on 5 or 6 watts — the taller antenna simply "sees" further and over obstructions.

Fixed VHF vs Handheld: Why the Mounted Set Wins Close to Shore

Coming into a harbour to call the marina office or a nearby boat, the instinct is to grab the handheld — it's right there in the cockpit. In most marinas that's the wrong choice, and understanding why tells you something fundamental about how VHF actually works.

Last updated: 7 July 2026 · By Askolds Hermanis, Founder & Sailing Instructor (SkipperCheck / Nautica SIA, since 2008)

Quick answer: Near the harbour, use the fixed set on 1 watt, not a handheld. The masthead antenna sits above the breakwater and the surrounding masts, so it keeps a clean line of sight and reaches the far station even on low power — while a handheld at deck level is shadowed by the mole. On VHF, height beats power.

Watch: sample VHF radio lessons from the SkipperCheck SRC course (6 min).

VHF is line-of-sight

Marine VHF travels in an almost straight line. It does not follow the curve of the earth and it does not bend well around solid obstructions. Your range is set, above all, by how high your antenna is — because a taller antenna can "see" over a more distant horizon and over obstacles in the way. Power gets you a little more reach in open water, but close to shore it's height that decides whether the signal gets through at all.

The breakwater is in the way

A handheld is held at deck level — roughly a metre or two above the water. Behind a stone breakwater or mole, that low antenna is in the radio "shadow" of the wall: the mole blocks the direct line to the station on the other side. You key up, you push out your watts, and the signal simply runs into the concrete. Add the crowd of hulls, pontoons and other masts in a busy marina, and a deck-level handheld is fighting obstructions on every side.

Height beats power. A masthead antenna sits 12–18 m up — well above the breakwater and most of the surrounding masts. From up there it keeps a clean line of sight to the marina office, so it reaches the far station even on 1 watt, while a "stronger" handheld a metre off the deck is still shadowed by the mole.

So why 1 watt, not 25?

Every marine VHF set has a 1 W / 25 W power switch, and it's there for exactly this moment. Close in, you don't need 25 watts — the masthead antenna already has the height to do the job. And low power is good radio manners:

25 watts blasted across a packed marina overloads and desensitises the receivers on nearby boats, making it harder for everyone else to hear their own calls.
It reaches far beyond the boats you're actually talking to, adding needless traffic to channels other crews are trying to use.
On 1 watt through the masthead antenna you get a clean, strong call to the office or the next pontoon — and nothing more, which is exactly what you want.

The rule of thumb: drop to 1 watt in and around the harbour, switch to 25 watts once you're offshore and reaching for distant stations.

Understand your radio, not just the exam

Our online VHF (SRC) course covers how VHF really works — channels, power, DSC and the full distress procedure — with a realistic VHF/DSC simulator to practise on. Study at your own pace, take the exam online, get your certificate.

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Frequently asked questions

Handheld or fixed set in the marina?

The fixed set, on low power. It transmits through the masthead antenna, which clears the breakwater and surrounding masts. A handheld at deck level is easily shadowed by the mole — so the fixed set on 1 watt usually gets through better than a handheld on higher power.

Why 1 watt instead of 25 near the harbour?

At close range you don't need the power, and 25 watts overloads nearby receivers and clutters channels others are using. The masthead antenna's height means 1 watt is plenty to reach the office or the next pontoon. Use 25 watts offshore.

Does a breakwater block VHF?

It can block a low antenna. VHF is line-of-sight and doesn't bend around solid walls, so a handheld behind a mole may be shadowed. A masthead antenna sits above the mole and keeps line-of-sight, getting through even on low power.

Is antenna height or power more important on VHF?

Height, in most situations. A taller antenna reaches a more distant horizon and sees over obstructions — which extends range far more than adding watts. A masthead antenna on 1 watt often beats a deck-level handheld on 5–6 watts.