DRM in SDR Console
Simon Brown • January 5, 2020
Why I haven't added DRM to SDR Console
I'm often asked to incorporate a Digital Radio Mondiale (DRM) receiver into SDR Console. The reasons why I haven't done this are:
- Patent / royalty issues with the audio codec, and
- The Dream project works well.
Brendan Wahl, WA7HL, co-Moderator, of the DRM North America Newsgroup explained the legal minefield recently. The text below is reproduced with his permission.
Hi all, got some background here for you. I've been following DRM since the beginning, and still admire it for its broadcast quality and capabilities.The DRM system was originally written by the Frauenhofer Institute in Germany, with the first software for personal use requiring a license key that cost the individual listener somewhere around ~€49/$49. I've got one somewhere, but I haven't had to use it since the freeware "DReaM" came out. No key needed when using that software package, which is still available on Github IIRC. The original commercial software still works, but it's very simple and doesn't provide a lot of bells and whistles. I'm not sure it's available anymore.What happened was that the AAC codec (and it's variants, esp. XE-AAC...) was developed some years after the receiving software was first published with older codecs already available freely. The Frauenhofer Institute in the meantime had sold its work and code already done on that codec to Dolby Inc., who didn't want to give anything away. Hobbyists went from being able to receive all codec forms of broadcast DRM with little to no cost, to technically having to remove the FAAD.DLL file and receiving nothing, period. Since all DRM broadcasters switched to the XE-AAC codec due to it's efficiencies, hobbyists got left out in the cold with that shift. That .DLL file has been known to circulate privately, since even Dolby admitted that trying to get people to delete a file that they already had was like screaming in the wind.Currently, as I understand it and as Simon indicates, radio manufacturers and developers must pay a license fee upfront to use the now-Dolby owned codecs. The listeners no longer have to pay, but the commercial party 'pays' on their behalf. This would include Simon of course, since he is both a commercial and hobbyist software developer, working as one entity.Simply put, DRM is a minefield for someone like Simon. It's not only a bit of a coding time-suck, the potential legal exposure is horrible. It is a big enough issue that most radio manufacturers are simply avoiding the whole issue by not making DRM capable receivers. A Chinese manufacturer, Gospell, and a couple of Indian companies have stuck their financial necks out for DRM, since it is being introduced in both countries, but actual production of quality consumer equipment has been difficult, to say the least.I should note that SDRC works wonderfully with the DReaM software being fed via a virtual cable. Was listening to Radio New Zealand International just the other night while they were doing some DRM testing, had perfect reception using my HF+. Can't wait for my Discovery to get here!I'll back Simon on his choice of not including DRM. I use SDRC more than any other radio software, and I appreciate all of his his hard, SOLO, work on it. No wonder he needs our beer money...and of course, the canine is always hungry. I know, I have one too.73,Brendan WA7HLCo-Moderator, DRM North America Newsgroup
So there you have it. Thanks Brendan. If you want to listen to DRM use Dream and a virtual audio cable.
SDR Television v1.1.2 June 12th, 2026: Add option to disable audio, thus making more bits available for video, this is for use in DATV contests. Note: 66 ksps sample rate is still experimental, will be improved. Downloads are at the bottom of this page.
SDR Television v1.1.1 June 9th, 2026: Fixes a fatal bug in the Settings, Camera page. Downloads are at the bottom of this page.
Version 1.6.2 This release fixes two bugs in the new DX Spot feature. The spot age logic incorrectly affected spot display. When the map was zoomed, station markers off the map would be displayed at the top left (0, 0). Downloads are on the World Map page . Version 1.6.1 This release fixes two fatal bugs in the new DX Spot feature. When the graphics engine is restarted, resources are correctly released. Fixed a resource leak when processing the MoseMove logic. Downloads are on the World Map page . Version 1.6 This release adds the display of DX Spots. Display spots are submitted to PSK Reporter which in turn are relayed by a MQTT Broker running on a high performance Akamia node. Spot Format Each spot consists of these fields: Sequence Frequency Band Mode Signal level Time stamp Sending station call, square, country Receiving station call, square, country Note: The country is the ADIF country. Spots are displayed as they arrive, currently no on-demand database. Bandwidth To reduce bandwidth from the broker, filtering is required for 80m up to and including 15m. Filtering requires at least one field below to be set in a definition: Receiver callsign, square or country. Sender callsign, square or country. Without filtering the bandwith from the broker could be excessive. For LF and VHF+ no filtering is required due to the lower number of spots sent on these bands. In a later version the bandwidth restriction may be reduced.
Version 1.6.1 This release fixes two fatal bugs in the new DX Spot feature. When the graphics engine is restarted, resources are correctly released. Fixed a resource leak when processing the MoseMove logic. Downloads are on the World Map page . Version 1.6 This release adds the display of DX Spots. Display spots are submitted to PSK Reporter which in turn are relayed by a MQTT Broker running on a high performance Akamia node. Spot Format Each spot consists of these fields: Sequence Frequency Band Mode Signal level Time stamp Sending station call, square, country Receiving station call, square, country Note: The country is the ADIF country. Spots are displayed as they arrive, currently no on-demand database. Bandwidth To reduce bandwidth from the broker, filtering is required for 80m up to and including 15m. Filtering requires at least one field below to be set in a definition: Receiver callsign, square or country. Sender callsign, square or country. Without filtering the bandwith from the broker could be excessive. For LF and VHF+ no filtering is required due to the lower number of spots sent on these bands. In a later version the bandwidth restriction may be reduced.
Version 1.6 This release adds the display of DX Spots. Display spots are submitted to PSK Reporter which in turn are relayed by a MQTT Broker running on a high performance Akamia node. Spot Format Each spot consists of these fields: Sequence Frequency Band Mode Signal level Time stamp Sending station call, square, country Receiving station call, square, country Note: The country is the ADIF country. Spots are displayed as they arrive, currently no on-demand database. Bandwidth To reduce bandwidth from the broker, filtering is required for 80m up to and including 15m. Filtering requires at least one field below to be set in a definition: Receiver callsign, square or country. Sender callsign, square or country. Without filtering the bandwith from the broker could be excessive. For LF and VHF+ no filtering is required due to the lower number of spots sent on these bands. In a later version the bandwidth restriction may be reduced.
SDR Television v1.1 May 18th, 2026: This is the official v1.1 release , code exactly the same as 1.0.16 which has survived testing for a few weeks. Lots of improvements since the last official kit. As with any software project, there's always room for improvements and new features, but for now here's a stable solution which works well with the QO-100 satellite. Many thanks to Sigi and the DATV test team. Downloads are at the bottom of this page.
SDR Television v1.0.14 April 12th, 2026: A new kit, lots of improvements since the last official kit. As with any software project, there's always room for improvements and new features, but for now here's a stable solution which works well with the QO-100 satellite. Many thanks to Sigi and the DATV test team. Downloads are at the bottom of this page.
SDR Television v1.0.9 March 13th, 2026: A new kit, lots of receive improvements since the last official kit. As with any software project, there's always room for improvements and new features, but for now here's a stable solution which works well with the QO-100 satellite. Many thanks to the DATV test team. Downloads are at the bottom of this page.
First Impressions
