Data on HF Radio

Data on HF Radio What offshore sailors can do with data on HF radio Samples of Email, Position Report, Weather GRIB File, Weather Bulletin and Weather Fax, Nadi/Fiji Fleet CodeWho provides data service Where the stations are locatedHow we do data on HF radio Step by step instructions for using Email, Position Reports, Weather GRIB Files, Weather Bulletins, Weather Faxes, Nadi/Fiji Fleet CodesAirmail helper application usage, HF Terminal and Telnet session usage Sailmail & Winlink Network ArchitectureSailmail & Winlink stations worldwideWhat software is required Airmail & helper applications installation for Ham and non-HamAirmail configuration for Ham and non-HamSailmail & Winlink maintenance/upgrade (see Appendix)What hardware is required General hardware component layout RF suppression components Wiring diagrams for various receivers Cable matrix for various receivers AppendixTom Baker - BCA Fleet of 2006

Email SampleEmail Sample using Airmail Client Software and Winlink 2000 Telnet Connection

Position Report SampleIntermar Position Reporter showing VA2BIC (Claude Gagnon & Carmen on SY-CORAIL IV)

Weather GRIB File SampleWeather GRIB file data can show surface wind speed & direction, atmospheric pressures and surface temperatures in much more detail than Wfax. This sample is using Mscan Meteo File Viewer Software

Weather Bulletin Sample

Weather Bulletin Sample from Winlink 2000 Catalog

Weather Fax SampleWeather Fax Sample Using JVComm32 Software

Nadi/Fiji Fleet Code SampleNadi/Fiji Fleet Code Sample is displayed using PhysPlot application

Data on HF Radio What offshore sailors can do with data on HF radio Samples of Email, Position Report, Weather GRIB File, Weather Bulletin and Weather FaxWho provides data service Where the stations are locatedHow we do data on HF radio Step by step instructions for using Email, Position Reports, Weather GRIB Files, Weather Bulletins, Weather FaxesAirmail helper application usage, HF Terminal and Telnet session usage Sailmail & Winlink Network ArchitectureSailmail & Winlink stations worldwideWhat software is required Airmail & helper applications installation for Ham and non-HamAirmail configuration for Ham and non-HamSailmail & Winlink maintenance/upgrade (see Appendix)What hardware is required General hardware component layout RF suppression components Wiring diagrams for various receivers Cable matrix for various receivers AppendixTom Baker - BCA Fleet of 2006

The SailMail Association is a non-profit association of yacht owners that operates and maintains a network of private coast stations in the Maritime Mobile Radio Service. The Association provides radioprinter (e.g. Internet email) communications for its members on a cooperative basis, in order to meet the private business and operational needs of the members' yachts. The SailMail Association provides worldwide coverage through the operation of 16 stations in North America, Hawaii, Australia, Southeast Asia, South Africa and Europe.Sailmail uses the same Pactor technology as the ham radio system, and supports Pactor-1, Pactor-2 and Pactor-3 on all frequencies at all stations. Airmail can be configured for either ham or Sailmail operation, or both. With the addition of a Sailmail configuration file, the same copy of Airmail can provide service for both the ham radio and Sailmail systems. This allows Sailmail to be used for business-related messages which are not permitted on the ham bands, as well in countries where ham radio third-party traffic is not permitted.Winlink2000 (WL2K) is a new ham-radio MBO system introduced in late 1999 by Hans Kessler N8PGR, Vic Poor W5SMM, Rick Meuthing KN6KB and Steve Waterman K4CJX. WL2K is fully integrated with the Internet, and uses Internet message forwarding to make user messages available at any station which they normally connect with. The Winlink-2000 system provides worldwide coverage through the operation of 49 stations in North America, Hawaii, Australia, Southeast Asia, South Africa and Europe.Airmail software operates as a "smart client" for accessing both WL2K and Sailmail networks. Sailmail/Winlink2000/Airmail Introduction

BoatComputerThe WL2K PMBO or Sailmail station is connected to the internet at all times

The InternetWL2K PMBO or Sailmail StationWL2K and Sailmail High Network ArchitecturePMBO: Participating Mail BoxAirmail

BoatComputerOther computers, or CMBOs, organize and manage the network traffic.

The InternetCMBOs are transparent to users. They are redundant, and you never know they are there.WL2K Network Architecture (continued)PMBOCMBOCMBOCMBO: WL2K Central Mail Box ServerAirmail

Winlink 2000 (WL2K) Stations worldwide (over 6000 subscribed users, free to licensed hams)Besides contacting other boats and Internet users, you may order parts, schedule fuel delivery,obtain a tow etc. Stock transactions and other activities that directly or indirectly increase the size of ones wallet are not allowed

Sailmail Stations Worldwide (over 3000 subscribed uses, $250 US/year non-ham users)Besides contacting other boats and Internet users, Sailmail can be used for commercial purposes, such as arrangingbank transactions,buying/selling stock, etc.

Operating Procedure for Airmail Terminal Program (HF Radio)Posting message using HF Terminal program

Build email message and Post in Airmail Message Index (outbox) Turn on HF Radio and modemOpen the Airmail Propagation program (View+Propagation) from Airmail Message Index window to determine what station/PMBO and frequency to connect toOpen Airmail HF Terminal program (Module+HF Terminal) from Airmail Message Index window and select station/PMBO and frequencyListen to make sure frequency is clear, use headphones if engine is runningIf frequency is clear hit green button in Terminal Program to send messageIf transmit speed is dog slow (< 600 bps) give up and try either another frequency, another station or another time. 1400 bps to 3200 bps are good numbers to see. This is VERY important, dont beat a dead horse - try later when conditions improveSend message

Receiving message using HF Terminal program

Repeat steps 2 through 6 aboveIf receive speed is dog slow give up and try either another frequency, another station or another timeReceive message into Airmail Message Index (Inbox)

Email via Airmail Terminal Program (Sailmail & Winlink 2000 users)Terminal program within Airmail sending an email through the HF radio speedsending message

Operating Procedure for Airmail Telnet Client (Sailmail & Winlink 2000 users via Internet)Posting message using Telnet Client program Build email message and Post in Airmail Message Index (outbox)Open Airmail Telnet Module (Module+Telnet Client) from Airmail Message Index window and choose Telnet Client Station/PMBO from pull-down listHit green button to send message

Receiving message using Telnet Client program

Open Airmail Telnet Module and choose Telnet Client Station/PMBO from pull-down listHit green button to receive messageThe Airmail Telnet Client can be used for sending/receiving email, receiving weather bulletins, receiving GRIB files, sending/receiving position reports. In other words, everything you can do in Airmail Terminal Client at 4,800 bps max can be done through Telnet Client at Internet speeds. We often cruise around an anchorage looking for an open WiFi connection to use

Email via Airmail Telnet Client (Sailmail & Winlink 2000 users)Note: When using Winlink 2000 Telnet Client, the rules of Amateur Radio do not apply since you are not going out over the HF airways. Business type transactions are allowed but only in Telnetreceiving message

Example of Sending & Receiving EmailWe will email off for the text version of this web page so we know what to expect when we land in Opua, NZ. Airmail Telnet Client will be used but Airmail Terminal program would have also worked. The following steps apply for any email sent & received.

1. Add New Address2. New Address Ready3. Compose Email, Save and Post4. Outbox shows Email was Posted

Propagation Airmail Helper Application5. Check a few Propagation Reports if sending via HF Radio (View+Propagation)

6. Send Email8. Receive ResponseSend and Receive Email using Telnet Client7. Outbox shows Email was sentsending messagereceiving message

9. Inbox shows Email was received10. Read Text Webpage

Position ReportingLets folks at home share in your adventures. Gives them a map to track your progress

Do let folks at home know that the lack of an updated position should not be a cause for alarm

Remember that most position reports are removed if track is not kept current (more on alternatives later)

Position reports allow you to see other cruisers in your area

Dont report if near sensitive areas like Somalia Coast, Gulf of Aden, Red Sea, Venezuela etc.

Dont report if you dont want people to know where you are (running from the Law, bill collectors, mother-in-law etc.)

Lets find VA2BIC (Claude Gagnon & Carmen on SY-CORAIL IV)The Position Reporter web page within the Winlink 2000 system can be found here:http://www.winlink.org/aprs/aprs.htm

The Winlink 2000 Position Reporter (Ham users only, lookup VA2BIC in first column on left)There are over 6000 Winlink 2000 members and at any one time ~300 to 400 are sending in daily/weekly position reports. If the latest position report entered is over 7 days old, the call sign will not show up on the APRS look-up list until a new position report is entered. Click View position reports for VA2BIC

View All Position Reports for VA2BIC (Click Satellite + Hybrid)

View Position Report Detail (green positions are history, blue position indicates latest position)

APRS Position Reporter (Ham users only)Enter VA2BIC in Station Call Letters box

APRS Position Reporter (continued)Only latest position is shown with no detail available Just like the Winlink 2000 Position Reporter, the latest position has to be no older that 7 days in order for APRS call sign lookup to work

Yotreps Position Reporter (Ham and Marine call-sign Users.Click Yotreps at bottom of main Position Reporter web page)Data entry is through Airmail position report form. Hams can also call into Pacific Seafarer Net (14.300Mhz USB at 03:25 UTC ) and have their data entered into the Yotreps system. Yotreps mainly wants you to use their system when you are sailing offshore (coastal sailing reports allowed without weather detail) due to their tie into the Pacific Seafarer Net and various Search & Rescue (SAR) activities.

Yotreps Position Report Data EntrySailmail users enter position report detail using the Airmail (Sailmail version) position report form. Hitting Send Now button will enter position report in the Yotreps databaseHam users enter position report detail using the Airmail (Winlink 2000 version) position report form. Hitting Send Now button will enter position report in APRS database, check Copy to Yotreps box to also enter position report in the Yotreps database

Look up VA2BIC in Yotreps ID column and click on Position TrackYotreps ID will be either a Ham call sign or Marine call sign. Yotreps ID lookup can find positions that were entered anywhere from current time up to 1 year. The Yotreps reporting boats lookup web page can be found here: http://www.pangolin.co.nz/yotreps/reporter_list.php

View VA2BIC Position Track and DetailA quicker way to drill down to the VA2BIC position reports is using the direct link: http://www.pangolin.co.nz/yotreps/tracker.php?ident=VA2BIC

Position Reporter from the European Maritime Mobile Service Network or Intermar (Ham users only, Click Position Reporter at bottom of main Winlink Position Reporter web page)Available for use worldwide, free to all Ham users. Uses positions from APRS Database posted via Winlink 2000. Call sign lookup can find positions that were entered anywhere from the present time up to 1 year past

From Initial Screen choose Map Window button

Enter VA2BIC call sign in Yachtfinder box and hit Yachtfinder button

Hit YachtTracker link to show all position reports on large mapZoom in by holding down left mouse button and dragging a rectangle with your mouseLatest position has red boat icon

Nice Position Report Detail!A quicker way to drill down to the VA2BIC position reports is using the direct link:: http://srv1.intermar-ev.de/demisMap/findYacht.php?search=VA2BIC&absenden=+Yachtfinder+

But Wait theres More! (Hit VA2BIC Callsign link)You can show in one place the boat & crew detail, position report locations and detail data, multiple maps, web page link and email link.If you register (free) with Intermar they will provide a nice interface to all your data

Source: http://www.franksingleton.clara.net/grib.htmlWeather GRIB (gridded binary) File IntroGRIB is a code form used by operational meteorological centers for storing and exchanging meteorological charts and other patterns of wind, sea state, temperature etc. The information is put into a compressed digital, binary format that enables high speed transmission and reception. It is useful to sailors for the efficient reception of charted information using GSM, GPRS, Satellite phones or HF radio to Internet link. GRIB files augment the information one gets from Weather Fax reports. Most common GRIB data shown is surface wind speed & direction, atmospheric pressure and surface temperature. What is GRIB and why does it provide so much for so little?Where does the data come from and what is it?A major source is the US NWS (Numerical Weather Prediction) model, the GFS (Global Forecasting System) which calculates how the weather is expected to develop, For this purpose it defines the atmosphere on a three dimensional grid of points. The lowest level of this model is at about 20 meters above ground (or sea level). This is at a height where the pressure is about 3 hPa (mb) lower than at the surface of the earth.

From the forecast wind at this level and using algorithms embodying surface roughness and stability, the NWS derives a forecast at 10 meters. The forecast winds are also used to drive a wave model known as the MMAB Operational Wave Model (aka wwave3).

NWS wind data in GRIB format are available, free, from at least two sources. Saildocs provide the wind at the 10 meter height above sea (or ground) level. Global Marine Networks (GMN) provides wind data from the output of wwave3.

Using Saildocs GRIB files (Sailmail & Winlink 2000 users)Drag mouse in grid area to choose area for GRIB file in Airmail Catalog (Window+Catalogs+Saildocs), set GRIB Parameters and Request (dont use Subscribe at Sea)

Weather GRIB files (continued)GRIB file is requested via email, received GRIB file is shown in Mscan Meteo viewer

Weather GRIB files (eChart overlay)GRIB file is overlaid on eChart in MaxSea and Waypoint Entered

MaxSea Routing Module Calculates Waypoints based on GRIB DataWeather GRIB files (eCart Routing Using GRIB Data)

Weather GRIB files (continued)Generated Waypoints shown on eChart (view MaxSea Routing.avi movie)

Weather Bulletins (Airmail Winlink 2000 and Sailmail Catalogs) Updateable over the radio, the built-in Airmail, Winlink 2000 and Sailmail catalog of bulletins contains over 800 text-based and graphic weather products that bring the user just about every publicly available weather product type, worldwide. Weather fax images are only available to Winlink 2000 users.

Send for Weather Bulletins via Email

Weather Bulletin (continued) Resultant Weather Bulletin received by email

Weather FaxMany good HF radio weather fax programs exist. Most new ones tune radio through modem if frequency control cable is presentGetFax comes free with Airmail, bare bones program

JVComm32 is an excellent program with good reception and image controls ($70 US)

Mscan Meteo allows you to automatically only download faxes desired, skipping over others ($149 US)

When radio propagation is poor, PC time is being restricted or schedule will be missed, get the fax emailed to youVia Winlink2000 catalogVia satellite phone

Learn to read & understand Wfax charts: http://www.opc.ncep.noaa.gov/UsersGuide/UGprint.html

Weather Fax via HF RadioSize of received file is 30KB, cost $0.00

Weather Fax via Winlink 2000 CatalogRequest E Pacific 96Hr Surface Fcst 00Z WefaxWhen propagation causes poor weather fax reception or you wont be on board when the schedule runs, get the fax emailed to you

Weather Fax via Winlink 2000 Catalog (continued)Size of emailed file is 13KB, cost $0.0

Weather Fax via Internet (Satellite Phone)Size of emailed file is 70KB, cost ~ $3.00 US ($1.00 to send request and $2.00 to receive fax)

WMO Nadi/Fiji Fleet CodesLookup Nadi/Fiji Fleet code in either Saildocs or WL2K catalogRequest is Posted in Outbox and Sent

Received Nadi/Fiji Fleet code data shown in InboxThe encoded content is very compressed and only 2K in size

Nadi/Fiji Fleet code data is displayed using PhysPlot applicationPhysPlot is a free general purpose meteorological plotter with the ability to plot isobars, wind arrows, fronts, pressure systems sea temperatures and other data from a variety of sourcesSource:http://www.pangolin.co.nz/physplot/index.phpReference:http://www.yachtvalhalla.net/articles/fleetcode/fleetcode.htm

Airmail for Sailmail User Install (Airmail for Ham installation steps are the same)Note: Check box if using PTC-II USB ModemAirmail for Sailmail software: http://www.siriuscyber.net/sailmail/amsm32035.exeAirmail for Ham software: http://www.siriuscyber.net/ham/amhc32035.exe

Airmail for Helper Application Install (GetFax, ViewFax, Propagation Reporter)GetFax & ViewFax Software: http://www.siriuscyber.net/wxfax/Propagation Software: http://elbert.its.bldrdoc.gov/pc_hf/hfwin32.html

Airmail for Sailmail User ConfigurationEnter valid Marine Call SignEnter password to be used with Sailmail Webmail applicationEnter initial LAT/LON to be used in Propagation calculator

Airmail for Sailmail User Configuration (continued)IC-M802 Remotely Controlled Receiver Example

ICOM 710 Configuration Example

Radio Not Listed in Pull Down Box Configuration Example

Airmail for Sailmail User Configuration (continued)Telnet Session UsageWRD719 Telnet user was automatically addedClick green circle to directly connect to Internet

Sailmail Catalog TreeNote: Single request is far safer than subscribing to either GRIB file or weather bulletin

Airmail for Ham User Configuration (Sailmail already installed)Note: Configuration can be changed at any time (Tools+Setup Wizard)

Airmail for Ham User Configuration (continued)Allow email attachments, add Telnet User, verify required modules enabled

Airmail for Ham User Configuration (continued)Enable GPS input to Position Reports (Module+Position Reports)Check Enabled boxCheck GPS Input boxGPS feed from COM PortGPS feed from Pactor Modem

Winlink 2000 and Sailmail Catalogs Combined

Winlink 2000 and Sailmail Catalogs Combined (continued)

Installation (Hardware Needed)

A Professional Installation Generally Includes:

Interface the radio to the HF-modem in the technically "best" fashion. If there is an "accessory" jack available on the radio that includes the necessary signals, it should ALWAYS be used. The use of the "Mic" jack should be avoided. A HF-modem to SSB cable should be provided that has shields connected on both ends and that has ferrites installed on both ends.If the radio is capable of remote control (Icom M710, Icom M700pro, Icom M802, Icom M710RT, SGC SG-2000, SEA-235), provide the remote control cable. If necessary for the PTC-IIe or PTC-IIex, provide and install a USB-serial adapter. If necessary for the Icom M700pro, provide the CI-V or Icom OPC-478 level shifter for the pin jack. See details in the Application Notes.Update the firmware in the SCS PTC modem to the latest version. Upgrade the modem to include an electronic serial number (ESN) if necessary (old PTC-II and old PTC-IIe modems only).Install ferrites at both ends of all cables including the RS232 cable between the HF-modem and the PC, the remote control wire to the radio, the audio/PTT cable between the HF-modem and the radio, and the tuner control wire. Install a Line Isolator (next to the tuner) in the coax from radio to tuner (for details see the SailMail Primer).Check and if necessary improve the ground system and the ground connection to the tuner. (Do not compromise on this item.)Check and if necessary improve the routing of the antenna wire from the tuner to the backstay. Make sure that the antenna wire has stand-offs supporting it at least 2 inches from any grounded wires or stanchions.Adjust the audio modulation levels on the modem using a directional power meter. See the application note in the SailMail Primer on level setting for details.Evaluate the system for RF self-modulation problems.Evaluate the boat's other equipment (inverters, motors etc) for interference with the SSB. Either install filters or inform the owner of what gear needs to be shut off before using SailMail (probably inverters).If the radio can not be remote controlled, then program the radio with the SailMail frequencies, including the appropriate mode.Provide a printed copy of the latest SailMail Primer , T&C's, and the SailMail FCC licenses.Provide a backup copy of the AirMail download from the SailMail website download page, on floppy disks.Test the system and demonstrate the use of the system to the customer.

Source: http://www.sailmail.com/installa.htm

Installation (RF suppression components)Ideal world, no Ground Loop RF leaksReal world, with Ground Loop RF leaksReal world, with RF suppression components in placeSource: http://www.airmail2000.com/rfi.htm

Installation (IC-M802 example)

Installation (IC-706 RT example)

Installation (IC-710 RT example)

Installation (continued)Cables Needed Between Radio and ModemRadio Model/TypeAudio CableControl Cable For IIPro & IIUsb OnlyIcom 7109090 (6ft)**8081 (6ft)**Icom M710 RT9090 (6ft)**8081 (6ft)**Icom M700 Pro9090 (6ft)**8081 (6ft)**Icom 779090 (6ft)**8081 (6ft)**Icom 7890958081 (6ft)**Icom 70690958081 (6ft)**Icom 706 Mk II90958081 (6ft)**Icom 706 Mk IIG90958081 (6ft)**Icom 7079090 (6ft)**8081 (6ft)**Icom 71890958081 (6ft)**Icom 720Anot suitable for digital communicationsIcom 7259090 (6ft)**8081 (6ft)**Icom 7289090 (6ft)**8081 (6ft)**Icom 7299090 (6ft)**8081 (6ft)**Icom 730 not suitable for digital communicationsIcom 7359090 (6ft)**8081 (6ft)**Icom 7369090 (6ft)**8081 (6ft)**Icom 7379090 (6ft)**no control Icom 7389090 (6ft)**8081 (6ft)**Icom 740not suitable for digital communicationsIcom 745not suitable for digital communicationsIcom 7469090 (6ft)**8081 (6ft)**Icom 746 Pro9090 (6ft)**8081 (6ft)**Icom 7569090 (6ft)**8081 (6ft)**Icom 756 Pro/II9090 (6ft)**8081 (6ft)**Icom 761not suitable for digital communicationsIcom 765not suitable for digital communicationsIcom 7759090 (6ft)**8081 (6ft)**Icom 78009090 (6ft)**8081 (6ft)**

Radio Model/TypeAudio CableControl Cable For IIPro & IIUsb OnlyIcom 7819090 (6ft)**8081 (6ft)**Icom M8009090 (6ft)**no control Icom M8029090 (6ft)**8083Icom M8109090 (6ft)**no control Yaesu FT60081258130Yaesu 747GXnot suitable for digital communicationsYaesu 757GXnot suitable for digital communicationsYaesu 767GXnot suitable for digital communicationsYaesu FT81781208130Yaesu FT840MFJ-1272B8080Yaesu FT84781278085Yaesu FT85781208130Yaesu FT89781208130Yaesu FT92081238083Yaesu FT1000 MkV81238080Yaesu FT10081208130Yaesu FT100081238080Yaesu FT1000 MP MkV81238080Yaesu FT1000 MP81258080SGC 200080208083Furuno90869088Harris 50228020n/aKenwood TKM707not suitable for digital communications Kenwood TS130Snot suitable for digital communicationsKenwood TS140S9096no controlKenwood TS200090978080Kenwood TS430not suitable for digital communicationsKenwood TS4409096no controlKenwood TS450S90978097Kenwood TS480HX81208080Kenwood TS480SAT81208080

Installation (continued) - Cables Needed Between Radio and Modem

Kenwood TS50SMFJ-1272Bn/aKenwood TS570D90978080Kenwood TS570S90978080Kenwood TS680S90978080Kenwood TS690S90978080Kenwood TS850S90978080Source: http://www.farallon.us/webstore Installation (continued) - Cables Needed Between Radio and ModemRadio Model/Type Audio Cable Control Cable For IIPro & IIUsb Only

Data on HF Radio What offshore sailors can do with data on HF radio Samples of Email, Position Report, Weather GRIB File, Weather Bulletin and Weather FaxWho provides data service Where the stations are locatedHow we do data on HF radio Sailmail & Winlink Network ArchitectureSailmail & Winlink stations worldwideWhat software is required Airmail & helper applications installation for Ham and non-HamAirmail configuration for Ham and non-HamSailmail & Winlink maintenance/upgrade (see Appendix)What hardware is required General hardware component layout RF suppression components Wiring diagrams for various receivers Cable matrix for various receivers AppendixTom Baker - BCA Fleet of 2006

AppendixGlossary of Termshttp://www.winlink.org/Glossary.htmAirmail software for Hams: http://www.siriuscyber.net/ham/Airmail software for non-Hams:http://www.siriuscyber.net/sailmail/Sailmail main website:http://www.sailmail.com/Winlink main website:http://www.winlink.org/ OPC WFax Charts User's Guidehttp://www.opc.ncep.noaa.gov/UsersGuide/UGprint.htmlJVComm32 Weather fax:http://www.jvcomm.de/index_e.html Mscan Meteo Weather faxhttp://mscan.com/Sailmail Primerhttp://www.sailmail.com/smprimer.htmRFI Interferencehttp://www.airmail2000.com/rfi.htmWhat is GRIB codehttp://www.franksingleton.clara.net/grib.htmlUsing Airmail with Macintosh Computershttp://www.downwindmarine.com/sailmail/mac.htmUse of USB to serial adapters on Mac'shttp://www.sailmail.com/apple.htmHow to download a new PMBO frequency List ftp://winlink.org/New_FREQ.txtHow to download a Catalog replacement or Updateftp://winlink.org/Update_CAT.txtHow to change the file attachment size limitftp://winlink.org/attachments.txtHow to do Radio frequency controlftp://winlink.org/AirmCtrl.txtWinlink Instructions for the Internet Userhttp://www.winlink.org/instructions.htm#Internet%20UserWinlink Instructions for the Radio Userhttp://www.winlink.org/instructions.htm#Radio%20UserWinlink Weather siteshttp://www.franksingleton.clara.net/winlink.htmlThe global site for cruising sailors (Radio version)http://www.noonsite.com/text/CountriesThe global site for cruising sailors (Internet version)http://www.noonsite.com/Countries

Data on HF Radio

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