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Royal Yacht Squadron Weather and Communications Day. Communications Tim Thornton. Overview. Receivers – NAVTEX, radio, weatherfax etc Communications Hardware Choices Connecting to the Internet. NAVTEX. Network of transmitters with about 250nm range
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Royal Yacht SquadronWeather and Communications Day Communications Tim Thornton
Overview • Receivers – NAVTEX, radio, weatherfax etc • Communications Hardware Choices • Connecting to the Internet Smartcom Software Ltd
NAVTEX • Network of transmitters with about 250nm range • Mandatory 518kHz frequency always English • Optional 490kHz frequency may be in the local language Smartcom Software Ltd
NAVTEX Transmissions • Fixed 6 minute time slots every 4 hours for each station • Primarily for navigation warnings – every 4 hours • Secondarily for weather forecasts – typically every 12 hours • Urgent info may be sent between regular transmission time slots Smartcom Software Ltd
NAVTEX • Transmit every 4 hours • More navigation information than weather Smartcom Software Ltd
NAVTEX Coverage Smartcom Software Ltd
NAVTEX Reception Hints • Ground the antenna cable shield, and use good quality cable • Don’t mount by other vertical metal objects – masts, rigging, stanchions • Poor reception over land • Designed for use to seaward of the fairway buoy Smartcom Software Ltd
SafetyNet • Offshore version of NAVTEX • Transmitted over INMARSAT C (see later) • Worldwide coverage • Can be better than NAVTEX reception, e.g. in Eastern Mediterranean Smartcom Software Ltd
Radio Transmissions Numerous voice transmissions: • Local FM radio stations • Radio 4 on LW • VHF broadcasts Smartcom Software Ltd
Weatherfax • Weather maps sent over SSB radio • Northwood and Offenbach transmit in Europe • Long range reception – mid Atlantic • Takes about 10 mins to receive a map • A bit fiddly and needs some practice to get the best out of it Smartcom Software Ltd
Weatherfax Smartcom Software Ltd
Weatherfax Software • Bonito Board Terminal and RadioCom • Mscan Meteo • Xaxero Weatherfax 2000 • JVCommThese all generally receive and decode Morse, RTTY etc. Bonito will also plot out SYNOP weather reports sent over RTTY Smartcom Software Ltd
Communications Hardware Choices • Coverage • Facilities • Installation • Costs Smartcom Software Ltd
Coverage – Mobile Phone • Mobile phone – GSM and GPRS • Enhanced with external GSM antenna • Typically 10 miles offshore • See www.gsmworld.com for coverage etc. Smartcom Software Ltd
Coverage – Iridium • Worldwide • Except Poland, Hungary, N. Korea • Antenna must be outside Smartcom Software Ltd
Coverage – Thuraya • Satellite coverage Mediterranean, Europe, the Gulf, India • Also includes GSM capability • Two geostationary satellites Smartcom Software Ltd
Coverage – GlobalStar • Land and coastal waters – not global • Also includes GSM capability Smartcom Software Ltd
INMARSAT • 4 geostationary satellites • Coverage within rectangles • Blue: Mini M,Fleet 33 & 55 data,Fleet 77 high speed Smartcom Software Ltd
Facilities Smartcom Software Ltd
In the Pipeline… • Fleet BGAN – 492kbps – end of this year • INMARSAT/ACeS linkup – smaller, cheaper alternative to Iridium rolled out over next 2-3 years • Wi-Max – longer range WiFi starting being rolled out, range 5 – 32 miles • GSM HSPA – speeds of about 1.8Mbps Smartcom Software Ltd
Handheld phone Hands free / car kit to hold the phone Bluetooth to the PC, ideally Or cable or infra-red External GSM antenna for best range – best up high Antenna needs good quality cable Fixed Phone Use DECT cordless phone handset(s) Optional connection to fax machine Serial cable for data connection to PC GSM module can be hidden away Data generally faster than handheld phone External GSM antenna for best range – best up high Installation - GSM Smartcom Software Ltd
Installation - GSM Smartcom Software Ltd
Requires external antenna for reliable satellite link – simple connection via coax cable Serial cable for data connection to PC If handset is not designed to be fixed mount, ensure enough cable slack for use Installation – Iridium, Thuraya, Globalstar Smartcom Software Ltd
Installation – Iridium, Thuraya, Globalstar Iridium Thuraya Globalstar Smartcom Software Ltd
External antenna required, connected via coax cable INMARSAT C – small and light, 10cm diameter approx Fleet – diameter from 33 to 77 cm. Beware antenna weight on larger sizes! For packet and dial up services, need separate connections to the PC Installation – INMARSAT Smartcom Software Ltd
Installation - INMARSAT Smartcom Software Ltd
Costs (UK£ inc. VAT) Smartcom Software Ltd
E-mail over SSB • Requires an SSB radio and radio modem – equipment more expensive than Iridium for example, especially with high installation costs of an SSB • Not a plug and go solution • Service providers: • SailMail – www.sailmail.com • MarineNet – www.marinenet.net Smartcom Software Ltd
Connecting to the Internet Logon authentication Communications Link SMTP Server ISP POP3 Server Slower Data rate DNS Server POP3 Server Fast data rate Internet Web sites Communications device PC Smartcom Software Ltd
Using E-Mail Efficiently • Batch up your e-mails instead of sending individually • Use plain text for outgoing messages • Send links instead of images • Don’t include original message when replying • Increase server time-out to allow for slow connection and satellite delays • Disable messaging tools e.g. Windows Messenger, ICQ • Don’t use a web browser to read your e-mail Smartcom Software Ltd
SmartCom • Designed for fast operation over slow links • Sends and receives simultaneously • If line is dropped, resumes receiving mail where it left off instead of starting from scratch • Minimises the size of outgoing e-mails • Allows header preview of large e-mails, so you can leave them, download or delete • Optimises TCP/IP settings • Uses your existing ISP and e-mail addresses • £39 for GSM only, £69 for satellite and GSM communications Smartcom Software Ltd
SmartCom Smartcom Software Ltd
MailASail • Server based e-mail service • Uses your existing ISP • New e-mail address supplied • Minimises the size of incoming e-mails by converting to plain text and minimising header size • Can also remove any attachments • Also can remove non-text content from web pages for fast browsing – but this can cause problems with many sites • Annual or monthly subs - £140/year for each service Smartcom Software Ltd
Zap • Requires Outlook, not Outlook Express • Dial in to their server for e-mail, need a separate ISP for web access • Requires a new zap e-mail address • Compresses incoming and outgoing e-mails • Charged by volume of data throughput – can be expensive • £70/year + £0.35/kilobyte uncompressed Smartcom Software Ltd
OnSpeed • Web and e-mail compression • Images resized and compressed more on the fly • Doesn’t work with secure sites or some satellite phones • Use own e-mail address and ISP • Significant speed-up • Overhead of about 10kbits of data with each connection • £25/year Smartcom Software Ltd