Navtex from HF to wifi?

earlybird said:
Why this urge to have everything wireless on an iPad? To stay longer in one's bunk perhaps!
I've got a device that receives and stores Navtex messages and displays them at the touch of a button. It called a Furuno NX300.
Probably cheaper than all these converters, interfaces etc etc.
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Because the dedicated display hardware takes unnecessary space, draws unnecessary current, and is not future proof.

If there was a black box HF receiver that could receive Navtex (and other HF broadcasts such as DWD) then output them via bluetooth or wifi, then any display hardware could be used (MFDs, tablets) and software could be written that could (for example) display Navtex information on the iPad or MFD chart etc. How many Navtex users really plot the GPS coordinates of a temporary hazard such as dead whale, or survey ship operating area, or lost containers onto their charts?

HF Navtex and weather still has possibilities in the medium future, and any manufacture that develops a lead in interfacing HF broadcasts to non-proprietary hardware is likely to have an advantage when everything eventually switches to satellite.

FWIW, I wrote to NASA today and suggested that they make a version of their Navtex-PC interface that could work with bluetooth to any platform and they replied that it is something that they are considering.
 
prv said:
Not sure if they have that exact thing, but it's the kind of area that Wetterbox operate in.

Pete
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Was given an active antenna with some out of date software. Turned out it was a NASA one, the same as they use on their navtex rcvrs, the interesting thing was that it squirted out sentences that Telnet could read on a windows computer. Am sure it was nmea that i could see. So could something be done with one of these? I am in Ayamonte at the mo, picking up UK navtex as well as all the stations down the spanish and portuguese coasts on my old nasa navtex.
Stu
 
nigelmercier said:
You can't just hook up something with an RS232 plug on it to a serial to Wi-Fi converter and expect anything meaningful.
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Sometimes you can. NMEA-0183 for example...

skipper_stu said:
Am sure it was nmea that i could see.
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NRX and NRM sentences perhaps.

Sending NMEA-0183 data over wifi is something we've done to death on here. The only issue is a lack of software to display the results. A little googling reveals that ICS have some Windows software which does the business:
http://www.icselectronics.co.uk/leisure/nav6-options/enavtex (possibly some virtual serial port jiggery pokery needed to convince the app to read network data rather than from a serial port: I'm not a windows expert). Writing something for iOS or android doesn't sound impossible.
 
I've got a NasaMarine unit with a proprietary serial Bluetooth adaptor plugged into the port. You need to have a bit of technical expertise to set it up, but it will work with the pc application. I also have a basic android app for it. I know it's not wifi, but it's wire-free and you can get the data on your smartphone with no internet.
 
I purchased one of these, and yes it does work with a standard Nasa Navtex box, converting it to a WiFi access point. I have it working into an Android app that allows you to download the messages from the Nasa device and then search them by station code and message type.
 
NoHorizons said:
I purchased one of these, and yes it does work with a standard Nasa Navtex box, converting it to a WiFi access point. I have it working into an Android app that allows you to download the messages from the Nasa device and then search them by station code and message type.
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That seems like a way forward, but it should be simpler than that. Ideal would be an antenna that can receive Navtex over HF and send it to a box that can output the signal as text over bluetooth to a tablet.
 
Do you mean being able to see live messages arrive on your tablet? The Nasa device forwards all messages on arrival anyway. The app to display them would be feasible to write, but the app would have to run continuously and notify you of new messages. Maybe a filter for those you want to see?

One of the previous posts to this thread suggests NasaMarine are looking at producing a bluetooth-enabled navtex "engine". Certainly they have started releasing Bluetooth LE versions of their popular devices this year, with free Android app, but a charge for apple. If they upgraded the navtex engine and kept to the current philosophy of "logging in" to the engine and downloading to a client device, you would have the messages on your tablet to search whenever you wanted. Alternatively, an interrogative approach might be forthcoming, especially since BTLE struggles with bulk data transfer.
 
nigelmercier said:
I would imagine it would be relatively simple to build a device to interface to a NASA unit. I've got too many projects on the go at the moment, but it would seem an ideal job for an ESP8266
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Done something similar recently.

About 30 lines of code to:
1) set up connection to WiFi
2) register with an MQTT server running on a Raspberry Pi
3) set up serial port
4) read in data from RS232
5) parse and send MQTT data to topics, e.g. "appsRoom/Row1/Rack1/Temp 24.5" "appsRoom/Row1/Rack1/currentUse 135"

Had 1 NodeMCU per row and 1 Rasperry Pi - total cost for the Apps room was about £80

MQTT seems excellent for this sort of use, libraries available to make it easy. Would be relatively easy to have a topic for each station on Navtex (or each engine temp monitor, bilge switch etc.). You can then either use a MQTT app and subscribe to the topics of interest or write a little app that does it for you.
 
st599 said:
Done something similar recently.

About 30 lines of code to:
1) set up connection to WiFi
2) register with an MQTT server running on a Raspberry Pi
3) set up serial port
4) read in data from RS232
5) parse and send MQTT data to topics, e.g. "appsRoom/Row1/Rack1/Temp 24.5" "appsRoom/Row1/Rack1/currentUse 135"

Had 1 NodeMCU per row and 1 Rasperry Pi - total cost for the Apps room was about £80

MQTT seems excellent for this sort of use, libraries available to make it easy. Would be relatively easy to have a topic for each station on Navtex (or each engine temp monitor, bilge switch etc.). You can then either use a MQTT app and subscribe to the topics of interest or write a little app that does it for you.
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Feeling generous enough to share the code? :)

Wouldn't it be quite easy for the esp8266 to publish a Web page with the navtex messages as well?

Ta
 
Revisiting this thread - an update an a question -

Now navtex is coming in from a nasa navtex engine through a precious usb/serial converter & getting saved as a text file on a raspberry Pi, the engine spits out the message as text over rs232 as it comes in or you can download the whole memory.

So is the a PC or Linux prog which will filter this from a text file? Don't think there is but you never know..

Not that it's a big deal anyway, you can just delete the bits you don't want as you go along I suppose .

The usb/serial will very likely be replaced with an ESP8266 to do it over wifi & free up the usb/serial port which was the original question, haven't tried that yet but should work OK.

So how it works - node-red watches the serial port and saves it to a file plus puts a message on a node red dashboard when a message comes in after adding time time it came in -

Plus a couple of inject nodes to send commands to the Nasa to either get the version just for checking it works or to download the whole memory. I had to send the new line in Hex a couple of times to get it to work OK but seems stable enough -
send for version - 0x0D 0x0A $V 0x0D 0x0A 0x0D 0x0A
send for entire memory - 0x0D 0x0A $S 0x0D 0x0A 0x0D 0x0A



One BIG benefit is you can cut and paste lat & long straight into opencpn for gunnery areas or whatever, really handy!

So it *should* be not too difficult for someone who knows html to program an ESP8266 to create a little web page to view navtex messages on any tablet/mobile etc :cool:
RFTnlRA.png


And stuff like this comes out to file

10/10-10:40 - Navtex came in0<


>GE11
09 2014 UTC NOV 17
WEATHER BULLETIN


STATE MET AGENCY OF SPAIN


TARIFA NAVTEX SERVICE AREA




ISSUED AT 2000 UTC ON THURSDAY 09 NOVEMBER 2017

VALID UNTIL SATURDAY 11 AT 2000 UTC

GALE OR NEAR GALE WARNING
10/10-10:40 - Navtex came inS: ALGERIA.

GENERAL SYNOPSIS AT 12 UTC THURSDAY 9 AND EVOLUTION.

RELATIVE LOW TYRRHENIAN SEA 1018 DPN. HIGH N AZORES 1040
SPREADING CENTRAL EUROPE AND N ALGERIA.

24 HOURS FCST

SAO VICENTE: NE 5 OR 6. MOD OR ROUGH.
10/10-10:40 - Navtex came in

CADIZ: NE 5 OR 6. MOD OR LOC ROUGH.

GIBRALTAR STRAIT: E OR NE 4 OR 5 BECMG VRB 1 TO 3 FM MIDDAY. SLGT
BECMG SMOOTH OR RIPPLED FM EARLY MORNING. OCNL MOD.

ALBORAN: E 4 BECMG VRB 3 OR 4 OVERNIGHT AND DECR VRB 2 OR 3 IN
T
10/10-10:40 - Navtex came inHE AFTERNOON. MOD BECMG SMOOTH. ISOL SHWRS IN S AT FIRST.

PALOS: N OR NE 3 TO 5 BECMG VRB 2 TO 4 IN THE AFTERNOON. SLGT LOC
MOD AT FIRST. SHWRS AND ISOL THUNDERSTORMS IN E.

ALGERIA: N 3 OR 4 INCR 4 TO 6. SLGT BECMG MOD OR RO
10/10-10:40 - Navtex came inUGH. SHWRS AND
THUNDERSTORMS.

AGADIR: NE 6 INCR 7 NEAR COAST. ROUGH. NW 3 M SWELL.

CASABLANCA: NE 5 OR 6. MOD OR ROUGH. NW 3 M SWELL. AREAS OF MOD.




a0
<
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Those obliging chaps at Nasa have obviously read my OP from long ago and have now built a Navtex receiver that transmits the messages on bluetooth to a tablet. Unfortunately for now it is just to Andrex tablets but the iPad app is in the pipeline.
 
Ric said:
Those obliging chaps at Nasa have obviously read my OP from long ago and have now built a Navtex receiver that transmits the messages on bluetooth to a tablet. Unfortunately for now it is just to Andrex tablets but the iPad app is in the pipeline.
Click to expand...

Shame it's not wifi... never mind :)

Are Andrex tablets nice and soft with puppies? ;)
 
GHA said:
Message type, transmitting station..

Not a big deal but might be nice
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I think you'd have to write that, but it really shouldn't be hard. In the past I'd have done it as a Perl one-liner filtering stdin, but a short Python script is probably more sensible.

Pete
 
prv said:
I think you'd have to write that, but it really shouldn't be hard. In the past I'd have done it as a Perl one-liner filtering stdin, but a short Python script is probably more sensible.

Pete
Click to expand...

Thinking about it should be easy enough to filter on the way in with node red then save as separate files.

Looks like the Nasa engine has start and end message flags as ">" and "<" , not ZCZC / NNNN so any other software might not be any use anyway.

Works though :cool:
 
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