The essentials in 30 seconds
- Fixed VHF mandatory: any sailboat venturing beyond sheltered waters (≥ 2 NM from shore) must have a fixed VHF with ASN/DSC + GPS + registered MMSI. This is the regulatory requirement under French Division 240.
- Portable VHF as backup: not mandatory but essential offshore (backup + use in dinghy/raft). The ICOM IC-M94DE (€374) with GPS + AIS-RX + DSC is the workshop standard.
- AIS Class B SOTDMA: premium upgrade vs Class B CSTDMA. 5 W output (vs 2 W), priority channel access, 5 s latency (vs 30 s). Visibility in racing and busy traffic zones.
- Essential 2026 combo: fixed VHF with AIS Class B SOTDMA + integrated GPS (B&G V60-B + GPS-500 = €1,154 ex-VAT) + portable VHF with AIS-RX. More essential than an EPIRB for coastal cruising.
- Workshop verdict: for 80 % of 30-45 ft sailboats, the combo B&G V60-B + GPS-500 (€1,154) + ICOM IC-M94DE portable is our standard. Total budget ~ €1,530 ex-VAT.
The marine VHF is the #1 communication tool. Ahead of satellite phones, EPIRBs, and coastal 4G. It’s the only channel that lets you talk directly to another vessel, a coastguard station, or a CROSS, and triggers a coordinated response within the European SAR chain.
This article distinguishes between fixed and portable VHFs, explains AIS classes (A vs B vs B-SOTDMA), presents the brands stocked by Skysat, and provides a workshop verdict by program. For distress beacons (EPIRB / PLB / MOB), see EPIRB vs PLB vs AIS MOB.
French legal framework — Division 240 and VHF obligations
Under Division 240, for sailboats ≤ 24 m:
- Sheltered waters (≤ 2 NM from shore): no VHF required (exceptionally rare).
- Coastal category (2-6 NM): fixed VHF with ASN (DSC) strongly recommended.
- Semi-offshore category (6-60 NM): fixed VHF with ASN mandatory + registered MMSI with ANFR.
- Offshore category (> 60 NM): fixed VHF with ASN + internal GPS + AIS-RX mandatory + 406 MHz EPIRB.
The MMSI number (Maritime Mobile Service Identity) is free via ANFR and takes 10 minutes to register online. Without a registered MMSI, ASN/DSC is useless — you can call, but no one knows who is calling.
Fixed VHF — functions and brands stocked
A modern 2026 fixed VHF integrates four standard functions: voice radio, ASN/DSC (Digital Selective Calling), AIS-RX (receiving AIS targets), and internal GPS (standalone). Premium versions add AIS-TX (AIS transmission = Class B transponder).
B&G V60 — basic AIS reception
The B&G V60 AIS-RX (€723) is the entry-level fixed VHF with ASN, internal GPS, and AIS reception. You can see nearby AIS-equipped vessels, but they cannot see you. Suitable for standard coastal cruising.
B&G V60-B — integrated AIS Class B transponder
The B&G V60-B (€1,049) adds AIS Class B transmission (CSTDMA, 2 W). You see AND are seen. This is the right compromise for most 30-50 ft cruising sailboats venturing offshore.
B&G V60-B + GPS-500 — complete solution
The V60-B + GPS-500 pack (€1,154) separates the GPS receiver from the VHF unit — useful if the VHF is below deck and requires an external GPS antenna on the cockpit for reliable reception. This is our workshop standard for refits on 35+ ft sailboats.
Portable VHF — backup and dinghy/raft use
A portable VHF is not mandatory but becomes essential once you leave the dock. Three typical uses:
- Backup for fixed VHF: in case of electrical failure or a man-overboard situation where the fixed VHF is inoperable.
- Dinghy/raft communication: in the dinghy while anchored or in the liferaft in an emergency.
- Crew-to-shore communication: harbor master, coastguard station, or another crew in port.
ICOM IC-M94DE — the 2026 portable reference
The ICOM IC-M94DE (€374) is our workshop standard for portable VHFs. It includes internal GPS, ASN/DSC, AIS-RX, and IPX8 waterproofing (floats). Practical battery life: 10-12 h in standby + 1 h transmitting. This is the portable VHF we install on all our offshore refits in 2026.
AIS Class A vs B vs B-SOTDMA
The AIS (Automatic Identification System) transmits on two dedicated VHF channels (161.975 and 162.025 MHz). Not all transponders are equal.
Class A — mandatory for commercial vessels
Mandatory for SOLAS commercial vessels. Output 12.5 W, latency 2-10 seconds depending on speed. Not applicable to pleasure craft (unless you have a megayacht > 300 GT).
Class B CSTDMA — entry-level for pleasure craft
The historic pleasure craft standard. Output 2 W, latency 30 seconds in busy traffic zones (channel access competition with Class A vessels). You are visible, but your position updates slowly.
Class B SOTDMA — the 2026 premium upgrade
New standard since 2018, widely deployed since 2022. Output 5 W, guaranteed 5-second latency, priority channel access. In busy traffic zones (English Channel, Bay of Biscay, Mediterranean in summer), this is a significant upgrade: your position updates 6× faster, and you are seen 2× farther away.
Upgrade cost from B to B-SOTDMA: ~€150-200 ex-VAT for equivalent hardware. For most serious offshore racing and cruising sailboats in 2026, this is the right choice.
2026 model comparison chart
| Model | Type | AIS | Internal GPS | Waterproofing | Price ex-VAT |
|---|---|---|---|---|---|
| B&G V60 | Fixed | RX only | Yes | IPX7 | €723 |
| B&G V60-B | Fixed | Class B CSTDMA RXTX | Yes | IPX7 | €1,049 |
| B&G V60-B + GPS-500 | Fixed + external GPS antenna | Class B CSTDMA RXTX | Yes (separate) | IPX7 | €1,154 |
| ICOM IC-M94DE | Portable | RX only | Yes | IPX8 (floats) | €374 |
Workshop verdict by program
Coastal cruising (≤ 6 NM)
Minimum regulatory requirement: fixed VHF with ASN, e.g., B&G V60 (€723). No need for AIS-TX (you can see others, but being seen isn’t critical in local waters). Total: ~€800 ex-VAT installed.
Offshore cruising (6-60 NM)
Recommended: fixed VHF with AIS Class B = B&G V60-B (€1,049) + portable VHF ICOM IC-M94DE (€374). You are visible to ferries, cargo ships, and other sailboats. Total: ~€1,530 ex-VAT.
Transatlantic / oceanic (> 60 NM)
Fixed VHF with AIS Class B + external GPS = B&G V60-B + GPS-500 (€1,154) + 2 portable ICOMs (one per crew member + 1 in the liferaft). Total: ~€2,000 ex-VAT.
Offshore racing
AIS Class B SOTDMA mandatory (upgrade ~€200 if the base model is CSTDMA). IPX8 waterproof portable VHF per crew member (3-4 units). Total: ~€2,500-3,000 ex-VAT.
5 common installation errors
VHF errors — observed in the Skysat workshop
- Unregistered MMSI. The VHF is installed, wired, configured — but the MMSI was never registered with ANFR. ASN/DSC works technically, but no SAR center can identify you. Observed in 1 in 3 installations during check-ups. Registration is free, online, and takes 10 minutes.
- Poorly mounted VHF antenna. On a sailboat, the VHF antenna must be at the masthead (maximum range). Mounted on the stern rail or backstay, range drops from 20 NM to 5 NM. All VHF range calculations (formula: 1.22 × √antenna height) assume the antenna is at the masthead. See our guide to VHF antenna placement on sailboats.
- Undersized coaxial cable. On an 18 m mast, RG58 cable loses 6 dB (75 % of power), RG213 loses 2 dB (35 %). Always use RG213 or Belden 9913 on sailboats — never RG58. Watertight connectors are mandatory.
- Disabling internal GPS and using external GPS via NMEA 2000. It works on paper. In practice, if the NMEA 2000 network fails, the VHF loses its GPS and can no longer transmit a position in an ASN/DSC call. Always keep the internal GPS active as a backup.
- Not testing ASN/DSC annually. The ASN/DSC test call (channel 70) should be performed at least once per year, ideally before each season. Without testing, you’ll discover on the day it doesn’t work. Procedure: VHF menu → ASN test → select channel 70 → send. Expected response: visual confirmation + receipt from CROSS in some cases.
FAQ — VHF + AIS in practice
Do you need a license to use a marine VHF?
Yes, the CRR (Restricted Radiotelephone Operator Certificate) is mandatory in France for full operation. ANFR exam, €80 ex-VAT, valid for life. For passive listening only (no transmission), no license is required. In practice, as soon as you transmit even a call to the harbor master, the CRR is mandatory.
Practical range of a sailboat VHF vs a cargo ship?
VHF range follows the Norton formula: range NM ≈ 1.22 × (√h_tx_antenna + √h_rx_antenna). Sailboat with 17 m mast (antenna at 17 m) → cargo ship with 35 m antenna → practical range 12 NM. Sailboat to sailboat (both 17 m) → 10 NM. Sailboat to coastguard station (80 m antenna) → 16 NM. More than sufficient for most coastal situations.
AIS via smartphone Bluetooth — reliable?
For visualization, yes. Most modern AIS gateways (B&G V60-B, ICOM IC-M94DE) broadcast AIS over Bluetooth or WiFi to tablet/smartphone apps (Aquamap, Navionics, Weather4D, etc.). For critical safety (collision avoidance), always keep a dedicated multifunction display — tablets can die, freeze, or be left below in the cabin. Redundancy is mandatory.
Difference between channel 16 and channel 70 ASN/DSC?
Channel 16 (156.800 MHz) = international distress and calling channel. This is where you say "MAYDAY MAYDAY MAYDAY" in an emergency. Channel 70 (156.525 MHz) = ASN/DSC channel = automated digital calling. More effective in noisy areas because it doesn’t require voice monitoring by other vessels — the DSC receiver wakes up automatically upon reception. In practice, send DSC on channel 70 AND voice call on channel 16 = double safety.
Do you need a VHF DSC Class D or Class A?
DSC Class A = SOLAS commercial vessels (cargo, ferry, cruise ship). DSC Class D = pleasure craft and fishing vessels. All modern pleasure craft fixed VHFs (B&G V60-B, ICOM IC-M93, Raymarine Ray73) are DSC Class D. This is the pleasure craft standard — don’t buy Class A for pleasure use; it’s more expensive and complex with no benefit.
Waterproof or submersible portable VHF?
"Waterproof" can range from IPX4 (splash-resistant) to IPX8 (submersible). For a sailboat VHF, aim for IPX7 minimum (30 min immersion at 1 m) and ideally IPX8 with floatation (e.g., ICOM IC-M94DE floats). A VHF that sinks without floating costs €374 to €800. The +€50 investment for floatation is negligible.
What antenna height maximizes range?
VHF range is close to optical range. For a 10 m sailboat mast (antenna at 12 m), range to coastguard station (80 m antenna) = ~15 NM. For a 15 m sailboat mast (17 m antenna), range to the same station = ~17 NM. Doubling height only adds ~15 % range — the marginal investment is low. Better to have a 1 m high-quality antenna properly mounted at the masthead than a 3 m antenna mounted on the stern rail.
Skysat is an authorized distributor for B&G, ICOM, Raymarine, and Navico. This article reflects our experience equipping VHFs on over 150 sailboats between 2020 and 2026, in cruising and racing. 2026 ex-VAT prices are indicative of authorized distributor rates, excluding MMSI registration (free via ANFR) and specific wiring.
