Good article by Ben Ellison on "how the mess of gadgets and wires pictured above is actually one sensible system for getting the most out of marine cellular." In this June 2004 column for Power & Motoryacht he talks about the actual performance of gear from, a.o., CellSocket, Shakespeare and Digital Antenna.
"I can tell you that Digital�s gear really works. I often saw 5- to 10-dBm improvements just by attaching my phone to the antenna, another 10 to 15 by adding the amplifier, which also seemed to flatten signal fluctuations. I was the strange guy repeatedly calling my own office answering machine from the boat (and pickup truck, as I also had a 3-dB car antenna) last season. I�d find a marginal reception area and then place separate calls with the cell alone and with the bidirectional booster attached. I could hear the difference both ways, first in my machine�s outgoing message and then when I got home on the messages I left."
Ocean Navigator has a very short, but also very positive, review of a book called 'HF Radio E-Mail for 'Idi-Yachts'', written by Marti Brown. It's a guide for setting up and using wireless e-mail through ham/marine SSB radio.
"The book offers the information simply, assumes limited knowledge on the part of the reader without being overly simplistic. Chapters include discussion of HF equipment, both ham and single-sideband radios and modem choices; rigging an HF radio in a sailboat; a discussion of various service providers and their offerings; a valuable chapter that describes how to make all your communications gear work together; and discussions on HF operation. The book�s CD-ROM includes related articles, software programs and samples of data sounds encountered in HF comms."
Two weeks ago there was a conference organized by Digital Ship, with one of the topics being on-board satellite communications. Although its main focus was on the larger shipping companies, some lessons can be learned for private yacht owners as well. You can find the report here (pdf).
"The result of the trial was that V.Ships saved 67 per cent of its communications costs on Fleet 55... ...EMS Satcom also calculated that Fleet 55 MPDS was 87 per cent cheaper than Mini-M for data communications with the same real life communications pattern, since mini-M was not designed to carry data."
"Dimitris Theodossiou, managing director of Danaos Management Consultants, created a stir by saying he could offer VSAT 64 kpbs always on for $400 a month, guaranteed 99.99 per cent availability, not including lease of the equipment, through Danaos' partnership with Broadband Maritime of New York."
My website statistics show me that for the last week, the post on Uniden's Mystic was the most read page. So here is an article by Chuck Husick on hand-held VHF radios that might be interesting to you. It has some tips and tricks on the workings of these devices and how to use them.
"As with all marine VHF transceivers, hand-helds must provide a 1 watt transmit power selection in addition to whatever higher power may be available (usually 3-6 watts). The general considerations that govern the choice of a fixed mount VHF set apply to a hand-held radio. The receiver is the most costly part of the radio and its ability to separate the signal you need to hear from interfering signals may determine the radio's worth. Transmit power is a secondary consideration. Remember, communication on the marine VHF band is essentially line of sight. Unless the radio is connected to a fixed antenna, mounted at some height above the water, the one watt low power setting will usually be all you need for clear communication. Further, unless the radio is connected to an external power source it will be drawing energy from its internal battery. Battery life is greatly extended by using the low power setting."
So when you're list of on board electronics and gadgets looks like a summary of this website, how do you make sure interference won't be spoiling the party? Well, start by reading John Payne's electronics column in DIY boat owner magazine's 2004#1 issue.
"Noise sources on a boat are often classified as radio frequency interference (RFI) or electromagnetic interference (EMI). They are major enemies of electronic systems, corrupting your GPS position fixes, degrading radio communications and causing general electronics performance problems. RFI is essentially interference and noise that is superimposed as a disturbance or voltage transient either on the electrical power supply or the data and signal lines. This is then processed along with the good data to corrupt or degrade the processed information."
Let's start with a quote from the article: "Sailors are preoccupied with weather." I guess that's a true statement, so where should we get our weather information? If you have a Practical-Sailor.com subscription, you can find out all about it right here. For those of you who don't, there is a free trial available...
"Once you step aboard the boat and drop the mooring, however, things change. Unless you have satellite television aboard, The Weather Channel is a fond memory, and (lacking an unlimited budget) high-speed Internet access is just wishful thinking."
Nice thread on how short SSB antennas operate and why. The discussion is concerning antennas that are shorter than a quarter wavelength. It's a bit technical, but you might find it helpful if you are into SSB.
"It may seem like semantics but there are a lot of people that get confused and think that when making the system resonant with a shorter antenna that the antenna is really the same as a quarter wave length antenna when there is a loading coil. It is far from that. Its radiation resistance and its feed point resistance are both much lower."
A quite funny quote from a Netstumbler forum thread shows very well that the combination of Wi-Fi and boating is still in the early adopter stage, and that 'wardriving' has its equivalent at sea....
"WARBOATING!!!! It was actually sort of tough to set this up (see photo below). The boat has a double door that snaps open, so I used the double doors to hold tight the NiteIze case flap. The case flap has a metal insert in the back and this is very strong. It held the Jornada, PC card adapter, Orinoco Gold card, yagi antenna, and wires in place for our entire four hour ocean voyage. I set the 8dbi yagi to point towards the shore. When we neared any boats I'd turn the yagi around if need be. (Or is this warshipping? Is that praying?) We received several pings from shore locations, but when we were passed by a police boat we also got a ping! Seems the sonar ping sound is perfect for being on a boat. I checked just now to see if we did indeed get a ping off the boat, it is WEP enabled for Seal Beach police. Good going guys! You're secure! (Warcopping?)"
With more and more marinas offering Wi-Fi internet access to boaters, it is very important to understand how you can get the most out of these possibilities. One issue that keeps coming back is the range within a user has access. Improving this range can be done in several (simple) ways. One of them is using 'high-powered' PCMCIA cards.
"So... given that a PCMCIA Wi-Fi card is a compromise, one way to overcome its limitations is to increase the transmitted power and receive sensitivity of the PCMCIA card. In the case of the SMC card, the transmit power is now 200 mW instead of 30 mw, and SMC claims "improved" receive sensitivity. My totally unscientific review testing tends to bear out SMC's claims."
I have posted many times on the differentapproaches and offerings for having satellite internet access anywhere at sea. Recently Boeing made a lot of headlines because of their plans to offer internet access via the same system as they are using to offer internet access in air planes. Many expected this to be a serious competitive threat to Inmarsat, a sort of incumbent in this area. Wi-Fi Networking News is comparing the different systems for offering in-flight internet access, but the analysis will probably teach us something about the future of satellite internet at sea as well.
"The 864 Kbps service from satellite giant Inmarsat delivered from its three fourth-generation I4 satellites scheduled for launch starting in late 2004 could dramatically change the future of aviation Internet access. This service is called B-GAN for Broadband Global Area Network. The service is in symmetrical 432 Kbps units with Tenzing recommending two bonded channels for 864 Kbps of bandwidth, although four channels and 1.7 Mbps are possible as well."
"I can tell you that Digital�s gear really works. I often saw 5- to 10-dBm improvements just by attaching my phone to the antenna, another 10 to 15 by adding the amplifier, which also seemed to flatten signal fluctuations. I was the strange guy repeatedly calling my own office answering machine from the boat (and pickup truck, as I also had a 3-dB car antenna) last season. I�d find a marginal reception area and then place separate calls with the cell alone and with the bidirectional booster attached. I could hear the difference both ways, first in my machine�s outgoing message and then when I got home on the messages I left."
Ocean Navigator has a very short, but also very positive, 
Two weeks ago there was a conference organized by Digital Ship, with one of the topics being on-board satellite communications. Although its main focus was on the larger shipping companies, some lessons can be learned for private yacht owners as well. You can find the report 
My website statistics show me that for the last week, the 
So when you're list of on board electronics and gadgets looks like a summary of this website, how do you make sure interference won't be spoiling the party? Well, start by reading John Payne's electronics 
Let's start with a quote from the article: "Sailors are preoccupied with weather." I guess that's a true statement, so where should we get our weather information? If you have a Practical-Sailor.com subscription, you can find out all about it right 
Nice 
A quite funny 
With more and more marinas 
I have posted many times on the