ASK THE EXPERT: MARINE ELECTRONICS
What are the pros and cons of digital and analogue radio?
Traditional analogue radio modulates one voice call for each 12.5kHz band, with no encryption. This can make it easier for anybody to monitor crew and guest movements, but despite their trusty and functional nature, analogue radios remain a massive security risk when it is an important consideration to keep communications private.
Digital radio encodes and encrypts the voice, allowing more channels for a frequency. This allows calls to be routed so that disciplines are separated. Deckhands and engineers can be contacted separately without the other radios picking up the conversation, while the captain can still listen to them all.
The main disadvantage with digital is the delay in calling, although this is only for about a quarter of a second (250 milliseconds). Unlike analogue, digital radio is feature-rich with text messaging, priority and private calling while enabling data transfer, which allows the transmission of alarms and service calls as well as the GPS location of handsets and tenders.
I have heard rumours of interference with other systems occurring in ports and on yachts...
The International Telecommunication Union (ITU) specifies a maximum of 10 12.5kHz slots for marine use, so there is a realistic chance of interference in crowded ports such as Monaco or Barcelona. As crew safety is paramount, a competent radio supplier can advise on using alternate frequencies, but care should be taken to avoid interference with land-based systems.
What is a repeater? Do I need one?
Simple radios work on a handset-to-handset basis, where the radios transmit and receive on the same frequency. The range is limited to the transmitting power of the handsets and is affected by the hull of the yacht or distance sway in tenders.
A repeater receives the transmitted signal unit using a number of internal and external antennas and retransmits on a different frequency at a higher power. A competently designed distributed antenna system (DAS) combined with a high mast antenna provides even coverage both in the lower decks and 5-6km out to tenders or into town.
Why am I experiencing issues with my digital radio system when I was promised high-standard performance?
A well-planned digital radio system is 50% hardware and 50% programming and planning. The recent growth in the popularity of digital radio over analogue has led to a mass supply of handsets within the market, with little or no thought given over to programming and an understanding of how the yacht operates. A dedicated radio system integrator will not just supply the hardware but will also provide the design and support to ensure that the system performance is optimised.
What are the new SOLAS regulations for fire radios?
The new SOLAS regulations (MSC 91/22Add.1) came into effect in July and states that firefighter radios should be ATEX-rated intrinsically safe, because using two-way radios in certain locations can present a potential safety hazard. A fire incident puts crew members into a stressful situation, and it is of paramount importance that communications are clear and focused. Integrating the radio communication into breathing apparatus simplifies deployments, and care should be taken to separate the fire team communications.
Adrian HicksDirector +44 (0) 1306 257250
ABOUT THE EXPERT
Channel 28 boasts a variety of products specifically developed for the marine industry, and in particular the superyacht industry, including its flagship product C-Comm. Now installed and in operation on an ever-growing number of yachts worldwide, C-Comm’s proven technology, security features and custom solutions have made it a true success. With all available solutions tailored to yacht-, crew- and owner-specific needs, our range of services and products available for the superyacht industry continues to expand and grow in line with industry and onboard technology requirements. Across other industries, Channel 28 is involved in a number of system solutions for a variety of commercial customers.