Atlantic communications.

[prv]

Note: Someone mentioned that they thought ISatphone Pro was "cheaper". Beware that we have seen a bunch of people try and save money this route last year and it seems a largely unsatisfactory system in practice. The device is somewhat tricky to setup for data, but the biggest problem is that it's around half the speed of an Iridium to download data. So although it looks slightly cheaper to buy, those saving almost instantly disappear in additional running costs

I looked at the ISatphone a few months ago (purely out of curiosity, as I have no offshore plans) and it looked quite good - but I was considering it only as a telephone, not for data. Would you say it stacks up for that compared to others?

Pete

 

[alant]

I hope to sail across the Atlantic this year. As with all things I do, it will be on a budget. I have a PLB and I am looking into SSB receivers. Are there any other ways to communicate that I should be looking into? Two way text would be fine. I just want routing information and some help with the weather.
Allan

Last time I came across, our SSB could only receive & our Sat Phone took ages to acquire a signal, so useless in any emergency. IMO, having just basic comms, concentrates the mind. Most of the time, your too far from anyone if you need help & too slow for major course changes to avoid bad weather, so best to learn how to deal with it.

If your really concerned, get an EPIRB & learn how to read the portents of bad weather.

 

[Toutvabien]

I hope to sail across the Atlantic this year. As with all things I do, it will be on a budget. I have a PLB and I am looking into SSB receivers. Are there any other ways to communicate that I should be looking into? Two way text would be fine. I just want routing information and some help with the weather.
Allan

http://www.ybw.com/forums/showthread.php?t=343240

 

[KellysEye]

> I've heard that most people use their boat name as a callsign but I thought you would need one like the HAM guys

Boats do use their boat name on SSB, hams use a call sign like we have for VHF.

For those thinking of buying a ham SSB: Marine SSB's have both Upper and Lower Sideband, ham SSB's have only Lower SB but can be modified to have Upper SB marine frequencies. Note: many amateur marine weather stations are on LSB.

 

[Conachair]

> I

For those thinking of buying a ham SSB: Marine SSB's have both Upper and Lower Sideband, ham SSB's have only Lower SB but can be modified to have Upper SB marine frequencies. Note: many amateur marine weather stations are on LSB.

Not sure what a ham SSb is? If you mean a ham radio capable of transmittinbg on the amatuer bands then very much doubt that you'll find one these days which isn't capable of recieving/transmitting USB/LSB/FM & AM.

Weatherfax is USB.

 

[Allan]

Last time I came across, our SSB could only receive & our Sat Phone took ages to acquire a signal, so useless in any emergency. IMO, having just basic comms, concentrates the mind. Most of the time, your too far from anyone if you need help & too slow for major course changes to avoid bad weather, so best to learn how to deal with it.

If your really concerned, get an EPIRB & learn how to read the portents of bad weather.

After scanning through most of the above, I think I have some sort of plan.
I will continue with my SSB receive only and laptop. We then have to decide between Satphone and Yellowbrick.
Many thanks for all the help so far.
Allan

 

[lenseman]

. . . I will continue with my SSB receive only and laptop. We then have to decide between Satphone and Yellowbrick.
. . . .

Good choice so far but remember that a Satellite phone does not give tracking for loved ones to follow. They sometimes wake up in the middle of the night and want to know where you might be and if you are all right . . . . ?

But with YellowBrick, they can just log onto YellowBrick and your position is immediately available without having to call you?

My position is below, well it was in April 2012:

http://my.yb.tl/surabayagirl

You can see from the above, the accuracy is within a few feet of the bow of my ketch. I was standing on the very end of the pontoon at the time.

You can set the transmit period for YellowBrick from a few minutes to 24 hours and every time it sends a transmission, a part of your credit is nibbled away. Every four hours sounds a good time if coastal sailing in Europe but once every 12 hours or 24 hours might be more beneficial if on an ocean passage.

YellowBrick is fully waterproof, I even want to say submersible as they fit them on the pushpit using Velcro for the ARC and they get a thorough soaking with the spray on a windward passage?


.

 

[balauru_furios]

Satphone and Yellowbrick are rather complementary
Lenseman explained very clearly the use of Yellowbrick. However the loved ones would like to chat to you every now and then, or even really need to talk to you about this or that. For this, the satphone simply cannot be replaced.

Also keep in mind that redundancy is always a good idea when it comes to communication. And a proper satphone installation (with external antenna) will allow you to call and be called even in the worst storm.

 

[Neil_Y]

Mscan is another weather fax/rtty software that I used. the best aerial was a wire (insulated) run up and around the backstay from a coax that ran from the radio to the transom. They are very sensitive to electrical noise, so often they don't work well in Marinas or near other boats, but it all changes a few miles offshore. If you are getting noise switch off everything, fridge motors and flourescant lightrs are common noise makers.

 

[capnsensible]

Last time I came across, our SSB could only receive & our Sat Phone took ages to acquire a signal, so useless in any emergency. IMO, having just basic comms, concentrates the mind. Most of the time, your too far from anyone if you need help & too slow for major course changes to avoid bad weather, so best to learn how to deal with it.

If your really concerned, get an EPIRB & learn how to read the portents of bad weather.

Lots of sense, I reckon. Actually when Im on delivery, I rent an Iridium for the duration and never had to wait long for a signal. On personal crossings, always been glad to get away from it all!

Having heard all the bootmenders going on on the radio nets, I certainly wouldnt bother with that!

 

[balauru_furios]

If a Iridium satphone takes ages to acquire a signal it has a defective (or badly connected) antenna. Unless you're near a tall building or something like that. Even the first Iridium handheld terminal (Motorola 9500) acquires a signal within 20 seconds.

With Thuraya it may take a while, depending on how often you use the phone and how far are the locations where you use it. (It needs to acquire GPS signal first and to update the position). If you haven't use it for a year and you power it on at 3000 miles from it's last location it will need 10-15 mins to get online.

 

[Martin_J]

Regarding GRIB downloads via Iridium...

I understand what Lenseman (and others) are describing about the set up of GRIB via email so that you receive small GRIB files for the area you are interested in. I also know that you can specify what time steps are in the GRIB and also that if you want to subscribe to perhaps next 14 forecast periods you send the request in a particular way and you will receive the regular emails. The GRIB files I will be looking at are perhaps just 75kb in size (uncompresses) so not a huge amount to download.

What I am trying to understand is the mechanics of actually receiving the GRIB file on board and whether or not something like the MailASail Teleport-IT subscription is actually required for reception of these files.

 

[Conachair]

I understand what Lenseman (and others) are describing about the set up of GRIB via email so that you receive small GRIB files for the area you are interested in. I also know that you can specify what time steps are in the GRIB and also that if you want to subscribe to perhaps next 14 forecast periods you send the request in a particular way and you will receive the regular emails. The GRIB files I will be looking at are perhaps just 75kb in size (uncompresses) so not a huge amount to download.

What I am trying to understand is the mechanics of actually receiving the GRIB file on board and whether or not something like the MailASail Teleport-IT subscription is actually required for reception of these files.

Have a look here..

http://weather.mailasail.com/Franks-Weather/Mailasail-Grib-Responder

Basically you send an email with the area and times plus some other bits in the subject line, then straight away you get sent an email with the grib attached. All free.

 

[Martin_J]

Conachair.. Thanks.. I fully understand that part - I have been receiving GRIBS that way for years.

What I hoped someone could explain is the mechanics of actually receiving that email (with the attached GRIB file) via an Iridium phone.

Places like MailASail seem to be selling an email subscription that just appears to give you a compressed email service.

The GRIBS I plan to download via Iridium will be 75Kb every six hours for about a week.

I didn't think I needed to sign up for what I think is an 'email' service just for that.

 

[Martin_J]

.. and you don't even need to send an email each time you want a file. You can include a 'subscription' element to the request and the GRIB servers will respond on a regular basis.

 

[Conachair]

Conachair.. Thanks.. I fully understand that part - I have been receiving GRIBS that way for years.

What I hoped someone could explain is the mechanics of actually receiving that email (with the attached GRIB file) via an Iridium phone.

Places like MailASail seem to be selling an email subscription that just appears to give you a compressed email service.

The GRIBS I plan to download via Iridium will be 75Kb every six hours for about a week.

I didn't think I needed to sign up for what I think is an 'email' service just for that.

Ah, must read harder I remember trying to work out how many Kb you would need before the compressed email service started to be worthwhile. It was ages ago and I think I failed anyway. From the last transat, and from memory, I was sending a small file every day or so and it ate up the minutes at an alarming rate. Quickly gave up on gribs and just used wfax instead onto a degen 1103 reciever. 75Kb 4 times a day sounds a lot for a budget boy like me

As for doing it, mailasail had a little prog on their site which configured the phone and you just click on connect and off it goes. Pretty sure you'll need a serial card though, don't think a usb/serial convertor will cut it.

Going anywhere nice?

 

[Martin_J]

Fastnet Rock and back.. the fastest route possible.. thus the need for GRIB.

 

[Martin_J]

Assumption changes now..

Let's assume the satellite phone is on board complete with serial data port for a laptop.. Pre-paid Iridium SIM card with perhaps 75 mins (4500 units) , 1 month, £90 ... here

What now is needed I guess is just a small application that will log into your email account where your GRIBs are being delievered, check the latest email headers and download the single latest email if it is new.

I assume this is all that is needed.. I just can't figure out why you would want to pay a monthly 'email' fee on top of the Iridium fee to get this application.

 

[lenseman]

Ah, must read harder I remember trying to work out how many Kb you would need before the compressed email service started to be worthwhile. It was ages ago and I think I failed anyway. From the last transat, and from memory, I was sending a small file every day or so and it ate up the minutes at an alarming rate. Quickly gave up on gribs and just used wfax instead onto a degen 1103 reciever. 75Kb 4 times a day sounds a lot for a budget boy like me

As for doing it, mailasail had a little prog on their site which configured the phone and you just click on connect and off it goes. Pretty sure you'll need a serial card though, don't think a usb/serial convertor will cut it.

Going anywhere nice?

If you send this file, it will give you the 24 hour wx for the Channel:

send grib:50N,48N,006W,001E|1,1|3,6,9,12,15,21,24,27

within 10 seconds only, I receive a GRIB file1k Byte in size.

Try it, send it to query@Saildocs.com

.

 

[Martin_J]

?????

I think I explained a couple of times that I knew (and Conachair knows) exactly how to set up the reception of a GRIB file for a specified area, with specified time steps and even with variable resolution to save data size...

Still wondering how to receive it via Iridium when out of 'normal' internet range and without paying a third party a subscription for email compression software.