Sat phone speeds

[Sundowner 39]

Never having used a Sat phone I am interested to know how long it might take to down load a Grib file assuming I was using compression soft ware of some description.
I appreciate the bigger the file the longer the time .......but is there a rule of thumb/average ?

 

[GHA]

Never having used a Sat phone I am interested to know how long it might take to down load a Grib file assuming I was using compression soft ware of some description.
I appreciate the bigger the file the longer the time .......but is there a rule of thumb/average ?

From unreliable memory a 10k or a bit bigger was between 1 and maybe 2 or 3 mins depending how good the signal was and how many times it dropped out. From mailasail with compression. Weatherfax is free and gives a much better big picture IMHO but both is very nice.

 

[ip485]

I cant give you a time because i havent timed it but i have just installed a fb150.

I thought uploads times would be reasonably painful but actually they are pretty quick, you really dont feel anything takes more than twice as long with a typical broadband connection - really surprised and impressed. Telephone calls are even better its crystal clear, no dropped calls and no time lag.

Sadly, all at a price.

 

[Bilgediver]

Never having used a Sat phone I am interested to know how long it might take to down load a Grib file assuming I was using compression soft ware of some description.
I appreciate the bigger the file the longer the time .......but is there a rule of thumb/average ?

There are system packages which can speed things up I believe this is one

http://www.mailasail.com/

 

[tcm]

Never having used a Sat phone I am interested to know how long it might take to down load a Grib file assuming I was using compression soft ware of some description.
I appreciate the bigger the file the longer the time .......but is there a rule of thumb/average ?

Right so from someone who has actually done this ... every few hours the Great Weatherforecaster at the other end of the sat phone Computers generate or get delivery of a computerised weather forecast map, for the whole world, for every hour into the future. So thats 168 (each hour) gurt big maps with arrows onnem. Oh, Maybe there's the pressure and or some other stuff, waves blah etc, but mostly we get the nice map with the arrows cos that helps sorta work out how it's gona be.

So, what you have to do is send a message defining your area of interest by giving lat long of bottom left and top right corners, (in that order, else you get a MASSIVE forecats of all the other area in those latitudes all around the world, except your bit dammit)

It's a dollar fifty a minute i think, and you can use as little as 20 seconds to send the initial email and er maybe a minute to get the mailbox contents incl the forecast of "as far as you can sail in the next week, daily" so that's over thousand miles wide, six forecast maps. So we might do that once a day on average ,more if bad system on the way. That might take over a minute but less than two minutes. Some days we'd just be looking at "the next day" forecast, much cheaper.

There is overhead in making any call with the tiniest bit of data, and if the signal is bad the system will try again, and if you have a booster then you get five bars the whole time and you get charged the same whether the signal is strong or weak. On most transats we spent about £100, so yerknow 5-10 quid a day not bad really, including some calls. One guy got his swmbo to call every day and they chatted away, apparently spent over 600quid in calls from her work

That mailasail stuff does the compression, you don't have to faff about with that.

 

[Monique]

Do you have HF? PM sent.

 

[RobbieW]

Have a browse around Mailasail's website - that'll give give you a starter for 10. He says the base Iridium speed is 2400 (remember your dial up modem from about 1988?), http://www.mailasail.com/Support/Iridium-Bandwidth. Then you can start to put tcm's post in context, my experience based on a single transat using a handheld satphone was that signal strength was the biggest problem and that more often than not it took several goes to receive each grib file - multiplying cost. Much of our routing on that trip came by Iridium text msg which could be sent free by some devious method & I dont think there was a charge to recieve - about 2008.

That wasnt a boat I owned, were I to install a satphone system it'd certainly use a fixed external antenna to try and maximise signal - but I bought a boat with HF

 

[Sundowner 39]

A big thanks to everybody who came back on this......... it helped a lot...............Cheers