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Starla - Log Day 20 - The air waves



Hello Everyone,

Distance logged today - 191 nautical miles. Distance to date this trip - 2605 nautical miles. Remaining miles to St Lucia 561.

As you can see from the log, we bettered yesterdays best ever daily distance by a few miles.

The wind has been 20-28 knots from the east. We are still sailing south east, below the direct course for St Lucia on port tack. Either on a wind shift (which is not forecast)or when the sailing angle is what we need, we will gybe on to starboard tack and make out way back up towards St Lucia. So you may see us go a little south before heading back up. That's sailing, not very many direct routes!

The sea state is still very uncomfortable, making life on-board more difficult. Cooking is a big challenge, but we are still managing well and spirits are good. Probably more to do with the ever decreasing distance to go.

It was funny trying to eat lunch today in the cockpit. I can verify, that given enough wind, soup will blow of your spoon before you can get it to your mouth. The solution to this, is to adopt an eating style like a praying mantis. Get some soup on your spoon, and a quickly as humanly possible, whip the spoon in to your mouth. Taking care not to dislodge the railings. Some would say that I eat like that anyway, not true!

No rain in the night, the morning has brought the sunshine.

Have you ever wondered how this log message gets to you? Well here is a little non technical description.

Some boats in the fleet are using a PC and fixed or mobile satellite equipment. The e-mail is sent from the PC to, lets say, a hand held satellite mobile phone, then the signal is sent from the boat to one of the orbiting satellites and relayed back down to earth, to an earth station, then on to the providers e-mail server, then in to the internet. This is a medium equipment cost and high operating cost solution.

We don't do that.

We have a high frequency radio set and radio modem. The e-mail is sent from the PC to the modem, the modem then operates the radio, selecting the chosen radio frequency sent from the PC e-mail application, and injecting the digital data in to the radio signal.
Just like you chose a particular frequency to listen to you favorite music station, we chose a frequency to broadcast our message on. The choice is made for a number of reasons.

Firstly, there are a number of land radio stations around the world, operated by an organisation called, SailMail. They all operate on different frequencies, so we chose one, to suit where we are sending the signal.

How do we chose where we are sending the signal?

This depends on the time of day, and how far we are from the land receiving station. The radio waves are actually reflected back to earth, from about 30 miles above the earth, by the Ionosphere. The Ionosphere behaves differently, a number of hours after sunrise and sunset for certain radio frequencies. For long distances the radio waves actually skip around the world, from the boat up to the Ionosphere, back down to earth, like a reflection in a mirror and back up again, before being reflected again to within range of the land radio station. The radio signal then goes through the land station modem in to the e-mail server and in to the internet. We have sent our e-mails via Belgium, Nova Scotia, USA, (South Carolina, Florida, Texas) Panama, Trinidad, Africa and the Red Sea.

This is a high equipment cost and very low operating cost solution.

If you are still awake at this point, well done.

If you have trouble sleeping at night, take the e-mail to bed with you and read it again!

Regards,

Starla Crew
(written by Steven Crake)

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