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ARC Report - Communications

One nice thing about taking part in the ARC has been the ability to chat with so many other skippers and get feedback on what works and what doesn’t on ocean passages. Over the next few weeks I will be posting a series of blogs on equipment and techniques based on our experiences and feedback from their ARC skippers as well.

This time I will cover communications, from VHF and AIS, to HF Radio and Satellite, and email/internet on the ocean.

Comms 1
Regular followers of my blog will know I am a big fan of AIS, and highly recommend having an AIS transceiver. We have a Raymarine AIS650, which is a class-B AIS unit. This standard has been designed for pleasure boats and means that it broadcasts your position at a low power, usually visible to others from 5-8 miles away. We regularly saw ships over 25 miles away, and they always see us at least 5 miles off. Very comforting to know they are seeing us as they come towards us... the ARC requires boats to have an AIS receiver so we know all other ARC boats can see us. Somewhat puzzling is the ARC recommendation that boats fit an AIS class-A transceiver rather than the Class-B designed for yachts. At any rate, I would estimate more than half the ARC boats have just a receiver - meaning we will not see them at sea. So this picture of our AIS screen as we left Las Palmas is less than half the fleet!!!

Of course everyone has a VHF radio these days, and on the ARC it is much more use than normal since we saw so many other boats on this crossing. Out in the open ocean I think we have not seen more than a handful of boats in all our miles at sea. On the ARC we saw boats almost every day! And it was nice to call them up for a chat! I highly recommend a handheld VHF as a backup in case of a problem with the main set.

HF Radio
The ARC regularly organizes SSB nets for the crossing. We have always made use of HF radio nets and the ARC nets were very fun. Even in the satellite age, for long-distance cruising the HF marine radio is still a great tool.

Comms 4
Satellite Phone
We bought an ISatphone-Pro and it was our first experience with a sat-phone. As a phone it is actually pretty good and we made a couple of phone calls from mid-ocean. The signal was good and did not have an appreciable delay. However we had planned to do SMS messages and also use the phone for internet access and in this case the experience it was not so positive.

I should preface this with the warning... I am still grumpy about all the trouble I had with the satphone on this trip. But realistically it was a good phone! Just not so good for data and SMS.

Perhaps you remember back about 20 years when you had a 9600 baud modem to get on the internet? Well, satellite phones are lucky to get speeds like that! The Iridium phone can offer data at speeds up to 9600 and our ISatphone reaches just 1/4 of that at the lofty speed of 2400 baud. There is no way to get on the internet for regular web access. The only possibility is email access. We understood that and had tested it out in Las Palmas before we got under way. it worked alright and would take 3-4 minutes of access to retrieve a few short emais plus our GRIB file.

One complaint I have is that the actual speed we got is not up to the promised 2400 baud. Connect time and signal dropouts on the voyage meant that we took many minutes just to connect and retrieve a few small emails.

Comms 2
We were mainly interested in downloading GRIB files for weather information - these would be just 10 to 50KB. At 2400 baud a 50KB file could download in 30 seconds but the handshaking and errors meant it could take more than a minute. In the middle of the passage we were unable to get the email to work at all. Despite holding the phone and trying to point it at the satellite we still had a 4 day period where we never managed to get any GRIB files downloaded. This meant up to 8 minutes of satellite time ($8US) with no emails received at all. All together over that 4 day period we used more than half an hour and got nothing at all! At our "pay-as-you-go" data rate of about $1/minute that was $30. As a phone it was good, but if you want email at sea look somewhere else. Now Inmarsat (who make the ISatphone) also make built-in units such as the Fleet-Broadband - starting around $6000 for a dome with monthly contracts for data starting about $100 for a few megabytes. ARC People with these units were much happier. You are still not getting high-speed internet access but email was reliable and they didn’t report the signal problems we had. Rates seem to start at $10-15 per megabyte for these options. That would compare to our "potential" rate of 1MB/hour =$60/Megabyte. Ouch.

The ISatphone can also do SMS messaging and we planned to do regular twitter updates using this feature. It is not exactly user friendly for text. Remember back before smart-phones when you typed texts through the number pad? That is how the SMS feature worked. Not so bad but our particular phone had a bug that caused it to mysteriously reboot while I was typing texts. Sigh... I hope this was just a random defect in our phone.... I will investigate further.

This is a nifty satellite tracker device that the ARC fits to every participating boat. It looks like a handheld VHF and was just Velcro-ed to the stern rail. This unit transmitted our position every 4 hours. The ARC website has an excellent tracker program which allowed family, friends and everyone to view the race! Yellowbrick also make these units for purchase (ours were special ARC race units) that apparently also allow you to use it to send texts from your phone. We haven’t tested this kind of unit but it seems interesting.

SSB Radio with Pactor Modem for Email
This is the other main email service people used on the ARC. We haven’t tried this but all the people who have one have been satisfied. Basically you get a Pactor Modem (~$1200) to connect to your SSB radio (such as the Icom M802). Speeds are comparable to Satellite at perhaps 4800bps. No web surfing but the big advantage is you aren’t paying for satellite time! The $250 annual fee for Sailmail HF service is much less than anything you might pay for a satellite service.
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