Internet via SSB

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Donheist

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Hello,

I have an SSB radio onboard. I have barely switched it on. Figuring it out is on one of my to do lists...

I have heard that I can use SSB for internet connections. I am not expecting streamed video but ability to queue up a few emails and getting weather would be a handy thing to have as prep for future extended voyages. Not sure I fancy the expense of sat phones.

How hard is this to organise? If I need to know about baud rates and other gobbledygook then I'll need help to set it up. Or is the sort of thing that needs constant tweaking and adjusting - do I need to go on a course?

How much might it cost given I have the SSB and antenna set up?

This is a medium term ambition so a general steer on achievability is what I'm after.

Thanks,
Mark.
 
The SailMail Primer is a good place to start, http://www.sailmail.com/smprimer.htm. That'll give you a grounding in terminology, speeds and other usefull stuff. SailMail are also one of the providers of another thing you will need to do what you want - a gateway between the radio signal and t'internet. Other providers are WinLink (you need a ham licence) and I believe Kiel Radio still provide a service.

You should have an LRC to operate the radio on marine bands, courses to achieve that may also cover email connections. If your goal is medium term you might think about a ham licence as WinLink is a free service provided by enthusiasts around the world.
 
The issue is line speed

Internet is greedy for bandwidth. Remember the days before broadband? 64kb/s on a modem would be considered hopelessly slow nowadays.

With a bandwidth of 2.4kH, which is typical for a SSB transceiver, you would be working at about 2kb/s at the best.

When you throw in the signal/noise ratio on a HF link it will almost certainly be much slower.
 
Beadle said:
The issue is line speed

Internet is greedy for bandwidth. Remember the days before broadband? 64kb/s on a modem would be considered hopelessly slow nowadays.

With a bandwidth of 2.4kH, which is typical for a SSB transceiver, you would be working at about 2kb/s at the best.

When you throw in the signal/noise ratio on a HF link it will almost certainly be much slower.
Click to expand...

Indeed - it's just about ok for simple email - provided you don't expect to send or receive attachments. As far as I know, the email solutions are not strictly speaking "internet connections" - you don't set up a circuit, then use the email client of choice. It's more a sort of telex-email gateway.
 
maby said:
Indeed - it's just about ok for simple email - provided you don't expect to send or receive attachments. As far as I know, the email solutions are not strictly speaking "internet connections" - you don't set up a circuit, then use the email client of choice. It's more a sort of telex-email gateway.
Click to expand...

Fair point on the 'internet connection', its more a mail hold and forward service. The email client is specific to the server as it implements the features described in the SailMail primer. With a good radio signal and Pactor III, I've found 2400 is a fair speed and occasionally I've seen around 3200 but it is quite variable. Attachments are a necessary evil if you want to recieve GRIB data, the AirMail program helps set up GRIB requests and gives some idea of the size file that you're going to be trying to recieve - 10-20k is not unreasonable.
 
I am not into HF/SSB myself, so may b treading where angels fear to go. I do use a receive only. Using the radio plus a computer via the audio output, you can receive DTTY and RadioFax – ie weatherfax. Both are very slow and the RTTY is pretty limited.

With two-way you can send and receive emails as long as they are pretty small. Sailmail used to have a limit of about 50 kb (at a guess.) However that means that you can use Saildocs to get GRIB information over a fairly large area. See http://weather.mailasail.com/Franks-Weather/Saildocs-Free-Grib-Files. and http://weather.mailasail.com/Franks-Weather/Receiving-Emails-By-Hf-Or-Ham. The second was provided by a RCC member.

Rather useful is to use email to get the text off a webpage. You simply send a mail to query@saildocs.com with the message “send URL”...In about 60 seconds you should get an email with just the text off the relevant page stripped of all the html. Good for forecasts. Try it with, say http://www.smhi.se/en/Weather/Sweden-weather/Sea-weather/sjovader_tabell_en.htm.
 
If you install a Pactor modem and register with Sailmail (240USD/yr) you then have email (not fast by modern standards but adequate for most purposes) and Saildocs. Via the latter you can download GRIB files and there is a menu for downloading forecasts from maritime agencies worldwide, although very general in remoter areas. There is also a facility for receiving faxed weather charts from eg Northwood. Details of availability in the appropriate volume of Admiralty list of radio signals.
I can recommend doing your LRC course with Yachtcom on the Hamble who will include all this in the course (as may others but I was happy with his service).
 
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Maybe you have one by now but I have a Pactor modem available for sale if needed. Very useful for high seas communications but after a few crossings my cruising is now closer to shore.
While a course in HF radio may be desirable it is not something the majority of users seem to do. It is quite easy!
Simon
 
As said, you can use email with a Pactor Modem and SailMail. If you download fax software you can also get synoptic charts and weather forecats, make your SSB has both output and input sockets. We used the latter but SatC for email.
 
KellysEye said:
As said, you can use email with a Pactor Modem and SailMail. If you download fax software you can also get synoptic charts and weather forecats, make your SSB has both output and input sockets. We used the latter but SatC for email.
Click to expand...

Sailmail now has a programme for reception of faxes called 'getfax'
 
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