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beau 19-03-2007 22:44

sat phones
I inquired about the purchase price of ssb radio or ham here in Australia and I was told I would be much better off buying a sat phone.

I plan to cruise from Australia north to the islands off new guinea, possibly fiji and then back west to Indonesia, langkawi malaysia etc

I have a business so I would like to stay in contact with emails etc does SKYMATE work in this area of the world.
However it would also be nice to download weather etc from the net.
I don't really need voice phone.
Any recommendations

swagman 19-03-2007 23:46

Hi Beau,

Not familiar with skymate, but the choices are really SSB / modem or satphone. Both will allow receipt of emails plus weather to a computer.

Basic difference is cost.

SSB / Modem high up front - zip ongoing - installation / antenna etc.
Satphone - lower up front - data / time costs ongoing - zip installation.

Bonus with SSB is also dialling into cruiser nets - but suspect if email is paramount - satphone may fit your needs.


Paul Elliott 20-03-2007 02:07

SSB email will have a moderate ongoing cost ($250 / year) if you use Sailmail. The ham-radio email system Winlink is free, but has some restrictions on commercial use, and requires a ham license.

Satphone has higher data rates than SSB email, and I've been able to receive fairly large WFAX images as email attachments via my Iridium satphone. These would not have been practical to receive over SSB.

I like Iridium, as the coverage is excellent, and the rates are competetive. I use "XGate" from Global Marine Networks for the satphone email service provider, and have been very happy with the performance. They have what looks like a good package for delivering weather info, but I haven't tried it yet -- instead, I get grib files sent to me from "Saildocs", and have a robot program that emails me daily WX charts from the gov't sites.

I do use SSB for marine and ham net voice work. I also use it for the occasional email, and regular weatherfax reception -- mostly to make sure there is a working backup should the satphone break.


Pura Vida 20-03-2007 04:09

Another advantage with a sat phone is you can take it with you. If you leave the boat to travel inland or if you have to abandon ship the sat phone is more practical than a SSB installation.

Sunspot Baby 20-03-2007 04:40

Skymates coverage map is at SkyMate | Wherever you go. Whatever you need.

I have been very satisfied with their products and services but have only used them on the East Coast U.S. and the Bahamas.


swagman 20-03-2007 05:36


Originally Posted by Pura Vida
Another advantage with a sat phone is you can take it with you. If you leave the boat to travel inland or if you have to abandon ship the sat phone is more practical than a SSB installation.

Er true. But if you were about to abandon ship you'd not know what other ship might be 50 miles away with the satphone - whereas the SSB could alert them to your situation.

Horses for courses etc.


hellosailor 20-03-2007 09:28

Beau, if you look at any of the sailing forums you'll find plenty of discusssions about this. Ham radio requires you to sit for license exams. SSB just requires a license fee. Either one requires a fast $1000+ for typical equipment and you may easily double that, plus the installation is always a semi-custom job not a simple plug-in.

But a satphone leaves you at the mercy of one vendor and racks up monthly bills as well. They are different tools with different abilities and if your budget allows, you might want both radio and satphone.

Pura Vida 20-03-2007 10:02

For calling out in an emergency I would call the Coast Guard or whatever equivelant resque agency for the local waters... now where did I put that number. Somebody dive down and get the number off the chart table! ;-)

The budget is a good point. When I told my cruising buddies locally that I was choosing a sat phone over SSB/HAM they were all up in arms. But for budgeting purposes the sat phone was chosen over the SSB for a cruise of no more than one year. Installation, airtime, purchase price, additional equipment, etc were about break even for that period with the phone being only slightly more expensive. Any time past that and the SSB had a price advantage. One last thing that made my decision was who I was talking to and when. SSB is great for the cruising nets, etc, but most of the people I need to keep in touch with do not have an SSB. In any case I know people who are using both.

Paul Elliott 20-03-2007 11:02

A Satphone doesn't necessarily incur monthly bills. While there are monthly service plans, I, and most people I've discussed this with, purchase pre-paid minutes. With this arrangement, there is no additional fee. The pre-paid minutes have a limited shelf-life though, with different rollover plans depending on how many you buy.

For satphone email, I do pay an annual fee for the XGate service. There are other ways to do this, but I've been happy with XGate.

Idiens 27-03-2007 04:16

Can anyone give me an idea of how much data they transmit a month when off-shore cruising? Primarily, email text and GRIB files. I can see the pro's and con's of SSB/pactor verses satcom on the surface, but want to fit SkyMate's $70/50kB/month into the picture.

Factor 27-03-2007 04:36

Beau - I think you can still get Federal Govt subsidy on sat phones.

Paul Elliott 27-03-2007 09:08

A GRIB file can be many sizes, depending on what data you ask for.

I usually get surface pressure and windspeed predictions at 24, 48, and 72 hours out, covering the area between most of the North American west coast out past Hawaii. The email with grib attachment for this is about 23 kBytes. I receive these once a day, so the grib's alone add up to 23kB * 31 (days) = 713 kBytes.

You can add wave-height predictions to the grib, and these add about 25% (as I recall), since the datapoints are plotted on a coarser grid.

You can also get predictions out to 192 hours (8 days), but most people don't believe anything past five days. If you are really into it, you can get the 500 millibar predictions via grib.

I suggest that you get some gribs from and play with them. start like this:
Subject: (anything)

send info
send index

Other email just depends on what people send to you. It's usually not very much. On VALIS, I also receive weatherfax charts via satphone email, through some software I run on my ISP's server. These charts take about 33 kBytes each. Most people get their weatherfax by receiving SSB broadcasts, but I am using satphone email for the convenience.

Your outgoing email is of course entirely up to you. We are pretty compulsive about it -- the family and friends back on land do appreciate regular communications. We send a daily blog report, occasionally with photo attachments. I can usually get the photos compressed and cropped down to under 10 kBytes each. I suppose our daily email output is about 20 kBytes, but most cruisers probably send much less than that.

Back to Idiens' question, you will have to limit yourself to minimal grib usage to stay under Skymate's 50 kB (kByte?) a month limit. This might get you five one-day forecasts in a month. It hardly seems worthwhile, and if this is indeed the limit I suggest sticking with SSB weatherfax., or switching to a different satphone plan. I use Iridium, and like it.

Idiens 27-03-2007 09:28

Thank you for that excellent reply Paul. It looks like SkyMate is simply not competitive, with SSB on one side and Iridium on the other.:)

hellosailor 27-03-2007 11:09

I would suggest that how much you, or anyone else, transmits will be a very individual thing. Most compuer users have no idea that by just "sending an email" they are using a dual format that sends HTML plus text in every message, and that HTML alone is typically 5x larger than plain text.

So, you could send one "short" message in dual format and send 3,000-5,000 characters, while a plain text version might be 500 characters or less. (With format and file overheads, yes, the difference can swell to 10x.)

I routinely see emails from AOL users that have six and eight nested levels of quoted messages hidden in them, and emails on (allegedly<G>) technical user lists that sometimes nest quotes 12-15 levels deep, making 90-95% of their message useless bulk.

The best way to check your needs, would be to prepare some traffic, send it to yourself, and count the message sizes. Then check then again to see if you can trim them. When Western Union used to charge by the "word" (and a Western Union Word was defined as five characters plus one space, six slots in total) sometimes we would always work at creative ways to say more with less.
Today's kids only think they have found something new with how they mangle IM text messages.<G>

Idiens 28-03-2007 00:35

Hellosailor - I would hope that since Skymate seems to use its own software to send and receive emails, they have already stripped the messages down to the essential text. However, they may not, then their prices are even more excessive.
I can see the need to be cautious with a Pactor modem - I suppose it transmits out of the SSB whatever the PC throws at it. However, is there not a simple way to reduce that outward traffic by using the Hyperterminal program rather than a modern HTML capable emailer (for example, or does Pactor have its own mailer)? For incoming mails, the service provider should also offer the facility to reduce the messages to the minimum text for transmission.

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