Digital Selective Calling was first introduced with the Global Maritime Distress and Safety System in the 90’s but has not yet played a significant role for racing sailors in Australia.

Boats with access to Digital Selective Calling have immediate access to benefits that the technology offers.

•    Emergency calling is improved by automation of the VHF radio mayday procedure via the DSC “Distress” call button. Once a DSC Distress Call is activated it is repeated at approximately four minute intervals for five transmissions. If you have a real distress you can activate the radio then get about dealing with the distress. If you are short-handed this can be a big benefit.
•    The boat can use individual calling send and receive DSC “Individual calls”. With receiving, an alarm will sound with ever increasing volume until the call is answered. It is more likely to be heard and responded to than voice calling because the boat will know someone is trying to contact them on the radio.
•    Boats can make position or rounding reports via position report calls. The call will only take a few seconds to make. It can be useful if the working channel is traffic heavy. The log will store proof of the call. If is more likely to be the superior option when atmospheric conditions are poor and voice calling is difficult.

There appears to be a broad misunderstanding of DSC because it is not part of the yacht racing culture in Australia. The technology is there, but simply not understood and not used. A factor behind this may be that radio operator licenses in Australia are perpetual, and we suspect most licensed operators were certified before DSC was introduced to marine radio training. Some navigators are exposed to DSC training when doing the commercial GMDSS certificate which has to be renewed every 5 years.

Training, or self-led education should be looked at given the emergence of AIS DSC MOB beacons and their use in search and rescue of a lost crew member.
•    The qualifications for the different radio licences can be found here
•    The manuals for the courses can be found here
•    VHF DSC radio manuals and YouTube channels offer a great way of seeing how equipment works
Once demonstrated and used, people are generally surprised and very enthusiastic about DSC.

Clubs who are organising authorities can also benefit from DSC.
•    The race committee can use individual calling to call a boat and will have a better chance of having the boat respond even if they are on the wrong channel. “We didn’t hear you calling us” situations are far less likely with DSC Individual calling. The whole process of getting in contact can be much faster than voice calling and can reduce working channel voice traffic. Clubs can divert a boat to a station other than the primary race channel if needed. This is useful if the club is calling to discuss a non-race related matter. All individual calls are logged in the radio for future reference.
•    Position report/request calls can be used as an alternative to voice call position/rounding reports. The organising authority and race committee just needs to provide this option in the race documents. Position report/request calls are more accurate; each is logged digitally and can help if the working channel is busy with other traffic. Race committees can even use position report request calls if they simply want to verify a boats position.

Regardless of all the benefits of DSC, keep in mind the VHF radio is better on than off. Channel 16 is the normal listening channel for emergencies and weather forecasts, and along with the channels listed in the sailing instructions, should always be monitored.

Australian Sailing recognises the kind and expert contributions from Cameron Berg and Will Oxley.

By Glen Stanaway