SDR Television Beta #3

Simon Brown • June 18, 2025

Major Change

Scroll down to the SDR Radio information. The bandwidths available for SDR Television when using a Pluto / LibreSDR have changed.

SDR Television

  • Now supporting vMix, this was a bug in the DirectShow camera support.
  • Diagnostics overlay now shows Symbol rate instead of Omega.
  • Fixed a (stupid) bug when a LNB offset was enabled.
  • Detects the version of SDR Console, install will fail if the required version is not installed.
  • Added Preset frequencies.
  • Added (actually restored) the Decode panel to the ribbon bar, you can now restart the audio & video decoders should they freeze.
  • Added a data recorder. This saves the data (IQ) from your SDR as a .WAV file in a folder you select on this page. Recordings help to diagnose decoding issues; transmissions can be replayed through SDR Console and streamed to SDR Television. The file format is:
  • 16-bit (unsigned short) complex (IQ) samples.
  • RF64 format (unrestricted file size) https://en.wikipedia.org/wiki/RF64 .
  • Fixed problem when received AAC switches between mono and stereo.
  • Improved matched filter (root-raised cosine).
  • Added Centre Receiver button to the ribbon bar. This centres the current signal in the receiver passband.
  • Enabling high-quality fractional resampling when decimating IQ data from the SDR.
  • Changed LDPC algorithm to use the Min Sum self-corrected algorithm, constant factor = 2.


Known Problems

  • Switching from a transmission using short frames to another transmission using normal frames and a lower sample rate may cause the program to abruptly exit. The good news - I have a data recording I can replay to reproduce this,


Preset Frequencies

Although this program is designed for use on the QO-100 satellite, it can also be used for terrestrial communication. This is where Preset Frequency definitions are used.


Frequency List

First create a list of frequencies you will use for receive and/or transmit. Select the list editor from: Ribbon Bar, Home, QO-100, Presets, Edit List.


Selecting

When you select a Preset from the ribbon bar, QO-100 panel the frequency is applied to both receive and transmit.


Receive

To select for receive only, go to the Configuration window in the Receive panel. The spectrum will be updated if a radio is started.


Transmit

To select for transmit only, go to the Configuration window in the Transmit panel.

SDR Radio

You will now see a different set of bandwidths when connecting to Pluto / LibreSDR: 1.5, 2 and 2.5 MHz. These have been carefully chosen to ensure the upsampling from the selected Sample Rate to the Transmit Bandwidth works as required. At a later date the upsampling logic will be extended, but for now this should fix an issue with incorrect sample rate selection.


For Pluto/LibreSDR the transmit filter width is now fixed at 100% and cannot be adjusted.

Download

This new kit requires a new version of SDR Radio.


SDR Radio

Download from either:


SDR Television

Download from either:

By Simon Brown November 1, 2025
November 1st, 2025 Analyser Analyser tag window change, as suggested by Jim. Analyser tags now saved and restored correctly. Analyser font size now supports small, medium and large. Analyser loads saved projects faster. Saving project now much faster and uses less memory. More display lines available if you have enough RAM: Less than 16GB then 50,000 lines. 16GB to 32GB then 100,000 lines. 32GB or more then 250,000 lines. Fixed minor font issue with definition window. Fixed issue scrolling when more than 32768 lines in display. Data File Playback Selecting a playback folder now creates the list of files much faster. Emulation Added a diagnostic check for the use of emulators. This code only works on W10 and above, so I dynamically load IsWow64Process2 from kernel32 which avoids issues on older versions of Windows. In the logfile you see something like this: 05:23:48.185: Vendor ....: GenuineIntel 05:23:48.185: Brand .....: Intel(R) Core(TM) Ultra 7 265K 05:23:48.185: - 05:23:48.185: x86 Emulation: 05:23:48.185: Process .......: 0x0000, "Not emulated" 05:23:48.185: Architecture ..: 0x8664, "AMD64" 05:23:48.185: - Favourites Updated the default 60m bandwidth. Changed Broadcast :: VHF CCIR title to Band II. Groups now have user-selectable files. Default definitions renames to main. Changed the ribbon bar, Selection entry to Options (see image below). The dropdown options have been replaced with a single window, allowing more room for text. Locked Receivers If the program is stopped or a favourite created when a receiver is locked, this caused problems with the receiver being locked but no indication. With this kit receiver lock state is not applied in a favourite definition. Logfile Automatically save the logfile when closing, really added so I can check program responding correctly to Shutdown and Restart. Old logfiles are purged after the program has been running for one minute. Logging Added logbook FA option as below, FA is the command to read/write RX1. Narrow FM Added 150Hz CTCSS squelch tone. De-emphasis is now optional, selected from: Ribbon bar, Receive, Mode..., Narrow FM. Persistent Display Got a crash inside the persistent display logic, my sanity checks weren't good enough so have improved this. Remote Server After connecting to a remote server, the input fields can now be edited to change connection parameters. Ribbon Bar View panel tidied up. Signal Meter (SMeter) Added more presets for the Signal meter, Ribbon bar, View, Spectrum, Signal Meter. Spectran ECO Changed SPECTRAN path order to pick up DLLs from the SDK folder rather than the main folder. Status Bar GPU, Audio entries on status bar now optional, selected from Program Options, Performance, CPU Memory. System Shutdown / Restart If SDR Console is running when the system shuts down or restarts then SDR Console closes gracefully. What happens - five seconds after SDR Console receives the SHUTDOWN message a timer calls the OnClose() processing, so you have five seconds to about the shutdown / restart. Text Size Fonts now scale correctly when a non-default Accessibility > Text Size is selected (see image).
By Simon Brown October 29, 2025
SDR Television v1.0.1 October 29th, 2025: Fixed a fatal bug in the receive AGC if the output soundcard sample rate is 96kHz or 192kHz. Downloads are at the bottom of this page.
By Simon Brown October 25, 2025
Previous: Version 1.5.2 This release fixes a bug, improves the user interface and adds a new calendar. Download link is at the bottom of this page.
By Simon Brown October 12, 2025
And the award goes to...
By Simon Brown October 9, 2025
Version 1.5.1 This is a mainly cosmetic update to version 1.5, nevertheless well worth installing.
By Simon Brown September 13, 2025
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.
By Simon Brown September 9, 2025
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.
By Simon Brown August 28, 2025
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.
By Simon Brown July 18, 2025
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.