Using SSB to Obtain NavTex Weather Reports

[kanaka]

hi folks
new member here,living in wales uk,hoping to go cruising long term soon ,in rival 34.
anyone know how [in laymans terms]to obtain navtex weather reports,useing an ssb radio and laptop ,keep it simple ,ta

[georgelewisray]

Wx-Fax on your computer requires a SSB (single side band) radio receiver, a patch cord from radio headphone jack to computer microphone input and some SW to turn sound data into a picture. Assuming you can figure out the fax transmission schedule and how to tune the SSB radio.

My radio: Sangean ATS-909 and Radio Shack DX-398


Good Luck!!!

Some tech stuff from internet:

HF-Fax

First at all you need a Single Side Band (SSB) Receiver, tune in to a Fax
signal, in the Upper Side Band (USB), at a frequency 1.9 KHz lower as given in theFrequencies lists.
Example to tune in Northwood on 11.086.5 KHz set your Receiver to 11.084,6 KHz.

The most Fax transmissions are send with a LPM (RPM) of 120 and a IOC (sometimes called Module) of 576.
Only stations with Russian equipment sometimes use RPM 60 or 90 and sometimes a IOC of 288.
Photofax transmissions such as from north Korea use RPM 60 and a IOC 352 with gray tones, and satellite rebroadcast use also RPM 120 IOC 576, with gray tones (4 or more bit Depth)

For software decoding best way is to decode with Black and White (2 bit Depth).

The Start-tone is 95 % black and 5 % white with tones with a duration of 15 to 20 seconds (called phasing) (300 Hz), the stopsignal is 450 Hz, and this is called Automatic Picture Transmission ( APT).

Now you should heard the typical "Scratch" sound from a Fax signal, with white-tones are send with 2300 Hz, and black-tones are send with 1500 Hz.

If you use Software for decoding Fax transmissions, use B&W with 2 bit Depth for the B&W weather charts

..................

http://www.cruisingclub.org/pdfs/dl....ts_wxsched.pdf

[mbu745]

Hello, I do have a Icom IC M 710, and also a world receiver radio Sonny. What do I need to receive weather faxes on my laptop. Regards. mbu745

[Hud3]

There's quite a bit of discussion in past threads about this...

http://www.cruisersforum.com/forums/...3-a-29243.html

http://www.cruisersforum.com/forums/...rfax-5363.html

http://www.cruisersforum.com/forums/...fax-16001.html

http://www.cruisersforum.com/forums/...ort-24778.html

[barnakiel]

I believe the original question was NAVTEX,

Thus:

Get jvcomm, or Mscan meteo software. Reed the manual and off you go. Both receive NAVTEX (Fax too).

Offshore I would use fax more than NAVTEX. Fax can be gotten over longer ranges. But the nav warnings are very convenient with NAVTEX.

Unfortunately, the simplest setups fail at one thing - you have to be tuned in / turned on to receive. Anything that is automated (e.g. a dedicated NAVTEX receiver) is a great help. A dedicated weather fax machine is also nice to have. Not cheap though.

b.

[Talbot]

I believe that knowledge of weather and how it works is an essential skill for the cruising sailor.

The best laymen's guide is on Frank Singletons web site at Franks-Weather / Frank Singleton's Weather and Sailing Pages | The Weather Window

[donradcliffe]

Navtex signals are 518 khz, and can be decoded with JvComm, but its not very convenient.

[basile]

I've been using jvcom for years now
receiving fax & navtex via a yeasu ft859
works fine
only trouble I have is on weak signals because the pc sends out some interference
greetz
Bas

[goboatingnow]

given that navtex dedicated receivers are pence, youd be better off buying one then rigging up you ssb,

[basile]

yes, that's the simpliest solution
though I am curious, what range do these dedicated receivers have
with my rigg I regularly receive stations more than 300miles ahaed

tropical greetz

Bas

[mbu745]

Hello Basile and the others, thank you for the information. I shopped around and this German program JVCOMM looks great. I gone use my world receiver radio Sonny because of the power consumption. Now I have to find the software to download. Regards. Mbu745

[goboatingnow]

my experience with a dedicated Navtex receiver , is that I get about 80 miles in general and sometimes, upto about 150 miles with certain stations. A useful feature to have is a GPS feed which allows the receiver to tune out stations that arnt useful and move to new stations as you sail along. Otherwise you gets loads of junk or corrupted mesages or just stuff that isnt revelant.

I find it my best weather forecast source. ( in Europe).