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Our goal for next summer is to be able to pick up weatherfax via radio. There's no way we'll rely on satellite again for downloading grib files. Our winter is dedicated to learning more about this sort of thing, and doing experiments.

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@neauoire wow, I had no idea about this very old tech! https://en.wikipedia.org/wiki/Radiofax

sounds like a really exciting & potentially rewarding project

@tty I saaw @amatecha figured it out a few weeks ago and we need to do too I think :)

@neauoire Any thoughts on how you'll recieve and decode the transmissions yet?

@cathos we've started collecting notes, there seems to be a sort of gradient here, from usb gizmos we could use near the shore, to quite cumbersome antennas to allow us to grab the signal when we're offshore.

We've got a little collection of software to handle the transmission, it's mostly windows stuff but I found two that'll work on linux. We haven't really done much experimentation in that so far so it's all fresh

@neauoire @cathos oh yeah I’ve been doing more research on it and have some ideas… there are so many options 😅 every option has its pros & cons of course. indeed an all-linux approach is totally fine. the software I used to decode the weather fax was the cross-platform “fldigi”. same software decodes the weather RTTY. the satellite stuff isn’t hard either. it all requires a bit of knowledge but it can be collected in notes as you’re doing! ☺️

@amatecha @neauoire What hardware are you using? At the moment, I have a small SDR receiver that should pick up those frequencies. I might test that!

@cathos @neauoire I’ve used a couple amateur radios (Yaesu FT-857D and Kenwood TS-480SAT) but a cheapo RTL-SDR dongle (specifically the RTL-SDR Blog V3 one) will work just as well, generally speaking. before I got my amateur radio operator certification I picked up tons of stuff with my RTL-SDR, and that’s part of what led me to want to be able to transmit too… I was picking up stuff from all over the world!

@neauoire @cathos You don't really need any fancy antenna to receive wefax on HF. On a boat you're supposed not to have too much noise. You just put up a small wire dipole on the mast and you're good. As others said, just use fldigi and an old HF receiver. I just received this map on 11MHz with my kiwiSDR.
Here you find the schedules:
https://www.weather.gov/media/marine/rfax.pdf

@neauoire @cathos regarding which radio to get, I'd suggest something like an ICOM IC-7100. It's not marine grade (they cost 3X!), but it's HF, VHF, UHF, the display is separated from the main unit, it has an integrated USB sound card so you connect the linux pc with fldigi just with a single cable. So, if you can install it in a protected spot on the boat, I'd say it's a perfect little radio for your kind of use.

@zabow @neauoire @cathos I get pretty good results with just a simple HF receiver (Sony ICF-SW7600GR) and the "HF Weather Fax" app on my Android phone.
I received this image an hour ago by just putting my phone next to the speaker of the receiver, so I didn't even use a cable to connect. Also, the receiver was placed indoors in our living room in a city - no additional outdoor antenna.

@hen @neauoire @cathos excellent result, but you cannot do that in a noisy enironment such as on a boat when it's windy and rough 😀

@zabow @neauoire @cathos Oh no, you would definitely need to connect the devices with a cable. :)
I was just trying to say that if you can get good results with a very minimalist setup in a bad location with a lot ot interference, then you'll shurely be able to get awesome results out on the ocean.

@neauoire We used to do this, with either a Funcube Pro+ USB SDR or a handheld SSB tuner with 3.5mm audio output. Then decoding via fldigi or JWX.

The Funcube gave better results than either of the portable SSB tuners and I liked JWX better than the rather confusing (but workable) fldigi.

Interference in built up areas is massive, so it's disappointing to play with in port. At sea or in remote bays, results are much better though.

Typical result: https://www.sigidwiki.com/wiki/File:Weatherfax_mapeurope.png

#SDR #WeatherFax

@yngmar @neauoire Wow, the homepage itself of JWX is a real treasure trove of very good suggestions by a real sailor!
I didn't know JWX, it seems something really optimized for WF and not do-it-all like fldigi.

https://arachnoid.com/JWX/index.html

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