Marine Radio Systems - VHF or 27Mhz?


Radio Frequencies: VHF vs 27Mhz

Radio Regulations

Marine radios are essential safety equipment and can be the only way to both communicate with other boats or marine rescue groups as well as receive navigational warnings and weather updates.

It is required by law that skippers and all crew to know how to operate all marine radios on board your boat, understand distress and safety frequencies, and how to properly format and transmit distress and safety messages.

The two main frequencies used for marine radios are VHF and 27Mhz. Both have their own advantages over the other depending on where you’re located and the size of your vessel. 


VHF is the preferred radio for short range marine communications. VHF channel 16 is for emergencies or initial calls and should not be used for routine messages or chat.

Maritime Safety Queensland and volunteer marine rescue stations monitor VHF channel 16 along most of the Queensland coast 24 hours/7 days and can respond to emergency calls.

All large vessels and an increasing number of smaller boats monitor VHF channel 16. Weather information is regularly broadcast on VHF channel 67.

Most areas in Queensland have a local chat or common use frequency. Your local marine rescue station can advise on this.

VHF users must have a Marine Radio Operator’s VHF Certificate of Proficiency (MROVCP) or the Marine Radio Operators certificate of Proficiency (MROCP) that covers both medium and high-frequency radios.

Example of Range of VHF Marine Radio based on Antenna Height and Curvature of the Earth



27MHz has a very limited range of around 10-15 nautical miles and is usually limited to "line of sight".

Despite it's decreased range compared to VHF, 27Mhz is useful for short range communication however you should check that a limited coast station is in your immediate vicinity before relying on it for your safety.

Most marine rescue groups monitor channel 27.88MHz, but larger vessels at sea do not listen to this radio. You do not need any qualifications or licence to own, fit or use this type of radio.

A short training session from a Marine Rescue unit will teach you the basic protocols of using a marine radio and how to get the most value from one – especially in an emergency.

Australian Emergency Radio Channels - 27Mhz and VHF

Ih you're interested in getting a VHF or 27Mhz radio for your boat, head to our marine radio page for a range of great Marine Radio & Audio Systems including transmitters and antenna bases designed to give you the best quality signal possible when you're out on the water.

Category: Safety

Related Articles

Safety Tips for Kayaks

Safety Tips for Kayaks

While laws for kayaking differ from state to state, here are some tips for making your next kayaking trip a safe one.