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Title: SSB and Iridium cost comparison
#12
I beg to differ with you... SSB weather is pretty limited. It takes about 2 hours to receive 6 forecast products. The quality of the reception can be very poor during these times of low atmospheric ionization. The wind and wave charts are also of very poor resolution providing you with 1 wind arrow over 60,000 square miles of ocean. Also, you get wind forecasts for very few time periods.

Finally, you have to turn on your rig at exactly the correct time to receive that forecast. With WeFax there is no such thing as getting a forecast right now.


A grib file over iridium however can provide you info for a large region at varying resolution. Typically you receive 1 degree grib files (one arrow every degree) over a number of forecast periods. 3days of wind every 72 hours or 12 forecasts for example.

So... besides getting picture perfect data at higher resolution you can get it any time you want. You can also download from NOAA and other sources the same data you get over your SSB plus much more. You can, for example, get animated satellite imagery.

As a fisherman you know how important sea surface temperature, currents, and plankton concentration are for finding fish. Sea Surface heights, salinity, and subsurface density layers are also very important. All this information can be gotten with a push of a button any time you want with an Iridium phone. This information is not available over SSB. Even if you had a pactor modem the performance of the system would be so slow that it would not be practical to acquire the data. And... there are currently no HF networks that could provide you this info since much of it is from comercial sources.

Sailboat users will appreciate the low power consumption of Iridium. An SSB receiving a WeFax requires 2 hours of operation with a 5Amp draw. It also requires an additional 2-5Amps for the computer system. So... 5-20 Amp hours can be drawn from the batteries to acquire 6 weather products. This power cost money in fuel, wear and tear on the engine and battery system, and on the crew having to listen to a noisy engine.

As far as emergencies go... The problem with EPIRBs is that
1. you don't know they are working since you get no ACKS from the emergency services folks
2. There are many false alarms with EPIRBS. So the emergency folks don't know right a way if you are in a critical situation.
3. There is no way to communicate the nature of the emergency to the emergency services personell.
4. The triangulation of the EPIRB signal is not very accurate.

With Iridium, on the otherhand, you can dial 911 and talk to the emergency folks. You can explain the nature of the emergency to them. They can get a Dr. on the line if the emergency is medical in nature. You can provide them with your exact location. YOU KNOW THAT SOMEONE RECEIVED YOU DISTRESS SIGNAL!

Finally, as the rescue ship approaches you can discuss rescue strategy.

You may think that an SSB and an epirb is suffient for you needs. I, however, would much rather an Iridium phone that could supply me with all of my weather requirements easily and any time I wanted it. Its also nice to know that such a device could effectively be used for safety should it be required.

-luis
 
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Messages In This Thread
[No subject] - by - February 8, 2010 20:41
[No subject] - by - February 8, 2010 21:20
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[No subject] - by - February 15, 2010 10:19
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[No subject] - by - February 15, 2010 12:40
[No subject] - by - October 4, 2010 05:36
[No subject] - by - October 5, 2010 11:26
[No subject] - by - October 16, 2010 02:55
[No subject] - by - October 18, 2010 13:12

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