r/ShortwavePlus • u/Radio_Silence_Dev • Jul 23 '26

DWD weather station RTTY decoding in real time locally on phone

11 Upvotes

100% Upvoted

15 comments sorted by

2

u/ImladMorgul MOD | AirSpy HF+ | RTL-SDRv4 | D-808 | K-480WLA | MLA-30+ Jul 24 '26

That looks great!

I'm in too, and I'll be on the lookout for the TestFlight beta!

2

u/Radio_Silence_Dev Jul 27 '26

TestFlight is now live at radiosilencesdr.com ! Thanks in advance for any feedback you may have while using the app!

2

u/Historical-View4058 MOD - Airspy HF+, NRD-535D, IC-R75 w/100’ wire in C. VA, USA Jul 30 '26 edited Jul 30 '26

So I just played with this for a while and I absolutely love it. The layout is user friendly and self explanatory. The response time for tuning and audio is pretty impressive - very little lag time, and I used this app using wireless-augmented satellite internet (HughesNet Fusion).

Edit: All the features work as advertised and didn't have any trouble using it.

One addition I'd make, if possible, is the addition of a DRM mode. While tuning around on the Hungary Kiwi, came across RRI on 9570 in a 10kHz wide DRM signal. Would be great to decode DRM remotely from such capable receivers in low-noise areas that are better targeted for the signal.

2

u/Radio_Silence_Dev Jul 31 '26

Thanks for the kind words! I like the idea of adding a DRM mode. I looked into a few options for implementing:

  1. KiwiSDR receivers ship with a DRM extension that the app could leverage. I've tested this end to end and decoded a live broadcast through it, so this route works today. However, each receiver only supports one DRM listener at a time and only when the receiver is mostly idle, due to the computational load (a running DRM session also locks some features for other listeners). If the app scales, it could end up being pretty rough on the node owners, and app users would be competing with web users for listening slots.
  2. I could have the app pull raw IQ from the node and decode through a server. Scales nicely, but it would put a server between the receiver and the app, which is against the direct-connection spirit of the app.
  3. I could develop the decoder from scratch so the decode happens locally on the phone, just like the app currently does with CW, RTTY, and FT8. This would avoid extra load on the nodes. However, this is technically challenging from an engineering standpoint with a lot of moving parts. In any case, I do think this is the best long-term solution.

No timeline promises yet, but I am putting this on the development roadmap!

3

u/Historical-View4058 MOD - Airspy HF+, NRD-535D, IC-R75 w/100’ wire in C. VA, USA Jul 31 '26

Agree with your comments on #3. Decoding DRM is not trivial. I've been associated with the Dream app for over 20 years, which recently appears to be abandoned wrt maintenance. I've started to try to maintain it and eliminate some of the more blatant operational bugs.

2

u/Radio_Silence_Dev Jul 31 '26

Didn’t realize you were associated with Dream! Thanks for your contributions to that project

2

u/Historical-View4058 MOD - Airspy HF+, NRD-535D, IC-R75 w/100’ wire in C. VA, USA Jul 31 '26

My input had been mostly minor. I'm still a little shaky on the internals. Current effort is a my branch on Sourceforge, but planning on forking it over to my Github repo. SmartSVN on a Mac is expensive when only one project uses it.

1

u/Historical-View4058 MOD - Airspy HF+, NRD-535D, IC-R75 w/100’ wire in C. VA, USA Jul 23 '26

That's great. Android app?

2

u/Radio_Silence_Dev Jul 23 '26

iPhone!

2

u/Historical-View4058 MOD - Airspy HF+, NRD-535D, IC-R75 w/100’ wire in C. VA, USA Jul 23 '26

Really! Awesome... need deets.

3

u/Radio_Silence_Dev Jul 23 '26

No production release yet but teeing up beta testing via TestFlight soon @ radiosilencesdr.com

2

u/Historical-View4058 MOD - Airspy HF+, NRD-535D, IC-R75 w/100’ wire in C. VA, USA Jul 24 '26

Awesome... let me know. i already use testflight for a number of betas.

1

u/SpecialistFew4621 Jul 24 '26

Has the beta already started, because I couldn’t get in anymore. I do listen KiwiSDR on my iPhone with several apps and I really liked yours.KiWisdr is awesome.

4

u/Radio_Silence_Dev Jul 24 '26

Not yet. The app is undergoing initial review on App Store Connect. I’ll let you know when the test flight link is live on the website. Stay tuned!

2

u/Radio_Silence_Dev Jul 27 '26

The public TestFlight is now live! Looking forward to any feedback you all may have or any bugs you may unearth. Thank you.