Friday, December 6, 2019

DRM tests from Hungary on 26 MHz - June 2019 to June 2020

Normally news items about DRM (Digital Radio Mondiale) tests on the short wave bands are of little interest to me except that this one is unusually at 26 MHz!

Avion DRM receiver

The Budapest University of Technology started a 1-year DRM test on the 1st of June 2019 and it will run until the end of May 2020.

The transmitted content is a 24-hour program, played out in a loop, compiled by the media partner of the project, Radio Maria.

They are transmitting on a frequency of 26.060 MHz with 100 watts into a 5/8 vertical.


Additional info..."The current short wave DRM transmission performed from the university has two main objectives: partly to demonstrate the value-added possibilities of DRM (xHE-AAC coding, slideshows and Journaline advanced text services accompanying the audio content), and partly to provide an opportunity for receiver manufacturers to test their products in real life. Since this is not a public or commercial service, the modulation parameters (transmission mode, SDC and MSC constellations, interleaving depth, etc.) can be freely changed at any time. Developers are, therefore, welcome to perform field tests with their devices in Budapest working in close co-operation with the broadcasting team of the Department of Broadband Infocommunications Systems and Electromagnetic Theory of the Budapest University of Technology. 




The landscape of the Hungarian capital is particularly interesting because the town is partly built on a flat area, partly on hills. The two sides are separated by the river Danube and are exhibiting various interesting wave propagation phenomena."



Looking at the display above, it looks as if the DRM signal is about 6 kHz wide.

The technical parameters of the demonstration broadcast in Budapest, Hungary, are as follows:

Frequency: 26060 kHz
EIRP: approximately 100 W
Antenna: 5/8 l monopole
Transmission time: 24/7

Thoughts.... Under Sporadic-E conditions, this should be heard around Europe. It has been heard already in the Netherlands so it should be possible.

As most people don't have DRM receivers, have a listen to Radio France Internationale on 3.965 MHz at night and you will hear a good strong DRM signal. If you listen on AM or SSB, you will get a good idea of what a DRM signal sounds like. If you hear the same type of signal on 26.060 MHz then it is very likely to the the test transmission from Hungary.

Links...
1) https://www.drm.org/

Addendum...
1) In response to this blog post, Rob PE9PE suggests the use of an online SDR to listen to the 26 MHz frequency... http://websdr.ewi.utwente.nl:8901/ and https://sdr.hu/

I wonder if there is an online DRM receiver in Europe???

2) Thanks to Bas PE4BAS for the info about the DREAM programme which can decode DRM signals. Info... https://www.drm.org/pc-based-receivers-and-software/

3) Info on 26 MHz from the DRM Handbook (Feb 2019)...





1 comment:

PE4BAS, Bas said...

It seems you can decode DRM with a computer using a program called DREAM. More info on the internet of course. Could be interesting just as a experiment. 73, Bas