Marine Radio
in Tasmania

Using your VHF radio


November 2010

By far the majority of larger pleasure vessels have, at least, a VHF short-range radio fitted but does it get used? Will it work for you when the moment is critical?

Whenever you are away it is a good idea to use your radio. The benefits of regular use of the radio are that you can be reasonable assured that the equipment is working properly. In an urgency or distress situation the last thing that you would want to fail is your communication systems so knowing that the radio has been working flawlessly to that point would indicate that it would work when really needed.

When was the last time you serviced your radio installation? Many fit their radios and forget to ever conduct checks.

Here is a quick checklist for your radio installation.


  • Ensure the batteries are kept correctly charged.
  • Keep batteries secure, clean and dry to prevent current leakage.
  • Clean electrical terminal connections and battery posts so no build up of white-green powder occurs.
  • Keep terminal clamps tight.
  • Ensure electrolyte is topped up to correct level by using distilled or demineralised water.


  • Keep the radio clean and salt free.
  • Carry spare fuses to the manufacturer's specification.
  • Check that the Push to Talk (PTT) button on the microphone does not stick.
  • Always replace a faulty microphone with one of the correct type. Do not swap between radios of different makes or models.

Antenna and Earth System

  • Check backstay insulators for cracks or other faults. Salt and grime build up will reduce effectiveness of transmission.
  • Keep all cable connections clean and tight.
  • Check that all cables do not show signs of wear from chafe or other mechanical abrasion.
  • Whip antennas can crack both externally and internally. Carrying a spare antenna is always worthwhile and is required for MF/HF radios where the backstay is used as the main antenna.

Other advantages of regular use of your marine radio are that the operator is completely familiar with its operation and is used to using correct radio protocols when making calls. In an emergency the operator will not have to think twice about how to use the radio, what frequency/channels is required for calling, what working frequency/channel is then used and will be confident in voice procedures.

Call a local Limited Coast Station for a radio check where the operator will advise you if your signal is weak or unclear. You will have heard someone say that a signal is "5 by 5" but what does that statement mean? It means that the clarity is excellent and that the signal strength of the equipment is very good as per the following list.


1/barely perceptible
3/fairly good
5/very good


Updated 25 July 2017. © Copyright. A Douglas 2017