SDR Television, Sept. 19th 2024
Simon Brown • September 19, 2024
QO-100 Beacon
SDR Television is a pure software solution for DVB-S2 H.264 / H.265 / AAC digital television. No hardware such as the MiniTiouner is required, just a SDR such as Pluto or Lime if transmit support is required, otherwise even a RTL SDR suffices.
Here's a recording showing SDR Television playing content from the geostationary QO-100 beacon. This software is still being developed, tentative preview date before February 2025, official preview April 2025.
- CPU load is low - typically 2% or less of an i5-13600F
- MER is around 10 dB
- Diagnostic display show key decoding status values
Much more to come over the next weeks and months including transmit support.
SDR Television This release is actually beta 6 with a few small updates, so I've left the beta 6 text here. I hope to start working on this in November 2025, adding the Gardner timing error detection which should improve the decoding with low SNR. Downloads are at the bottom of this page.
Hello Again I'm now back to 90% SDR Console support, so here's the first beta for at least eight months. Scroll to the bottom for a link to the beta kit. The source is fully archived, so crash dumps can be analysed.
SDR Television Improved phase detection at the start of each frame (SOF, PLS) which in turn improves sensitivity. Added 2,000 ksps receive, confirmed as working with GB3NQ. Sensitivity still not as good as a Serit 4334 NIM as used in the MiniTioune receiver, what's missing is synchronisation timing, I will be using Gardner timing error detection (TED). This will be added in Q1, 2026 when this project is extended for terrestrial use. Downloads are at the bottom of this page.
SDR Television Found and fixed an unused massive memory allocation (up to 10GB), may have caused systems to freeze. Fixed fatal bug in matched filter array allocation. Changed the default transmit bandpass shaping filter roll-off to 0.20 in transmit and receive. Please look at the images below and apply the change. SDR Pluto Now show the AGC gain and RSSI. Added Default link to select the recommended gain - Fast Attack, 0dB visual. Known Problems Add support for tracking transmissions with (?) non-standard PCR data, example is G8GKQ. Using Pluto & variants, sensitivity is not as good as a NIM (hardware tuner). Will compare with SPECTRAN ECO in a week or so.
Unexpected Beta #4 I wasn't planning to release another beta, but there was an error with a download link in the Blog post for Beta #3, also a few worthwhile improvements have been made, so here I go.
Major Change Scroll down to the SDR Radio information. The bandwidths available for SDR Television when using a Pluto / LibreSDR have changed.
BATC Net, May 22nd 2025 Here's a snippet from the British Amateur Television Club net on QO-100. I hope it doesn't scare you.
UI Refresh And More...
After too much grief, I've decided to stop using Wi-Fi to connect the small NUC systems in the computer room to my network: DX Cluster (Ubuntu) SDR Server (Windows) User Forums (Windows) These servers are in constant use, causing the wireless transmitter on my TP-Link AX50 to fail. By switching over to a wired network there's less demand on the wireless transmitter and the whole network has become far more reliable. In future I will only use Wi-fi when there's no alternative. I'm keeping a spare router ready just in case the AX50 fails.
