Three Ways to do RTTY
Weather Teletext Reception
'Old' and 'New' Methods
It’s shortly after Christmas and an editor’s thoughts turn to experimentation. I have been trying to receive some Weather Radio Teletext (RTTY) signals from the Deutscher Wetterdienst (DWD) again, the German Weather Service.
As you may have seen from previous columns in RadioUser magazine, there are several different ways to do this. I have picked our three here, depending on the equipment used.
On some of the pictures on this page, you will see my good old AOR AR7030, pressed into service again, together with its old friend, the ERA (Enterprise Radio Applications) Microreader, of which I have acquired a late model in 2021.
At 7645kHz (USB) the actual receive frequency is a little lower than what is advertised. I always learned that you should tune up to 1.9kHz off-centre for this kind of signal, but this is, naturally, a matter of trial and error.
If you look at the other screenshots here, you will see that I also used the new ATS25 radio, which will be reviewed in RadioUser in February 2022. This nifty little device is, of course, not as stable or well-built as the AOR, but it works very well for some useable monitoring.
As you can see, I connected it to a U-PHORIA UMC202HD sound card; the one I normally use for VLF work, at 192kHz resolution. The result was good signals throughout with SeaTTY and Zorns Lemma 11.42. Makes a nice little setup on your boat or en-route.
And, last but not least, a configuration involving the SDRplay RSPduo with Eugene Muzichenko’s great Virtual Audio Cable (VAC). No issues at all here, especially for longer-term signals resolution. The little picture in orange tones is the translation of the synoptic (synop) data by Zorns Lemma 11.42, one does not get that feature in SeaTTY. This is a weather report from Gander, in Canada.
Regarding Virtual Sound Cards, take a look at Mike Richards’s article in Practical Wireless, December 2021: 26, which is an excellent introduction if you have not worked with those before.
The ‘visualisation’ software used throughout is my new favourite: Friture. The aerial I have used in all of this was my Wellbrook ALA 1500 Loop and a Reuter RLA-3 for indoors.
Have fun reading and decoding your own RTTY data in whichever way you choose.
A Very Happy, Healthy and Prosperous New Year to All!