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Has anyone gotten wefax to work with openplotter using rtl-sdr? Is there a reason the weather fax plugin for opencpn is not part of openplotter? Is the AIS radio in the moitessier hat tunable?
Thanks
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I don't think the radio on the moitessier hat is tunable but I could be wrong.
With rtlsdr and dvb-t dongle you can tune but HF frequencies are difficult.
I used a board called an upconverter which makes reception possible but the result (using weather fax plugin) was slightly worse quality than $40 ssb receiver tecsun 600. In both cases I did not use a sufficient antenna but weather maps were readable.
So it is possible. Let us know your results and also very interested in direct mode which allows HF reception without upconverter (But even worse quality??)
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moitessier HAT is not an SDR receiver, it is a dedicated AIS receiver. You can play with some options but you will get only AIS data.
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2020-03-22, 11:28 PM
(This post was last modified: 2020-03-22, 11:33 PM by Josacraw.)
Any tips on getting the wefax signal using gqrx? I'm using the rtl-sdr v3 with a 30 foot length of cat5 cable strung up in a tree. The wire is plugged into the center pin of SMA jack. The Boston wefax is the closest to me at about 900 miles. Gqrx is set USB mode with everything else default. I see a signal spike at 12748.1khz but only hear static. I've also tried the new Orleans station which is about equidistant. I have looked into various shortwave antenna styles but effectively they are what I have done. Maybe I'm just to far away? I have tried night time as well knowing you should get better reception then. The sdr is definitely working as can pick up local FM stations no problem.
I can also pick up a series steady tones from low to high at the frequencies just below at 12746 and lower
Thanks
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After a long hiatus I am revisiting this concept. Turns out wefax reception is very poor when you live in a wooded area so I moved to an area with clear sky. I've been able to record and decode transmissions on my laptop using gqrx and fldigi.
I have been far less successful on openplotter using the same antenna and sdr. The reception is just so much worse! It helped to move the sdr from a usb hub to a directly into the pi. I've also tried using a 3 or so foot dongle cable to get a little distance. I can receive images but they are very poor.
I have yet to get the opencpn plugin to receive anything(by that I mean it returns a lightly staticed white image). I added the direct sample flag to the rtl_fm command under the scheduler tab and set the upconverter offset to 0 since I'm using a v3 rtl-sdr. Is there something else I'm missing?
Thanks!
Perhaps it would help to turn off the ais sdr on the moitessier hat while receiving?