DRM™ – Digital Radio Mondiale – Reception in New Zealand
Reception in New Zealand
This page documents some of the experimenting I have being doing with reception of digital shortwave broadcasts from my home in Wellington, New Zealand and my holiday cottage in Marahau, Tasman Bay, New Zealand. To date I have been able to receive broadcasts from transmitters located in the Netherlands Antilles, Canada, Portugal, the UK, Luxembourg, Morocco, Sri Lanka, Kuwait, Thailand, The Netherlands, Germany, Russia, China, France, Sweden, Norway, Chile, Austria, Spain, New Zealand, Australia, India, Ecuador, Bulgaria & Romania.
About DRM™
Digital Radio Mondiale, DRM™ for short, is a method of broadcasting on AM radio using digital signals rather than analogue – it’s like listening to an audio stream on the Internet, but broadcast on medium or shortwave radio rather than via the net.
In addition to potentially crystal-clear reception, DRM™ signals can also carry multimedia information in addition to the audio signal, or to carry multiple program streams on one signal:
(courtesy Michael Dressen, Germany)
DRM™ can also send web pages via shortwave
DRM™ – Screen caputures of VT Merlin sample Broadcast Website:
The following screen caputures are courtesy of Richard Beales in the UK. They were captured during test DRM data transmissions carried out by VT Merlin using a 1kW transmitter during October 2004.
Amateur radio operators are also using DRM™
(courtesy Carsten Knütter in Germany)
PY4BL – HB9TLK 14255 kHz
More information about ham application of DRM visit the HamDream web site.
I have also experimented with transmitting DRM around my house using the DReaM software, which includes a transmitter option, and a Jackson Harbor LF to HF Converter module which converts the sound card IF output up to the HF range. This has a range of only a couple of meters, but I have been able to transmit data and audio from my own LPFM radio station, World FM around the house. You can see some screen shots of weather station data being broadcast here.
You can learn more about DRM™ at these web sites:
The DRM logo is a trade mark of Digital Radio Mondiale Association and is used under license. DRM logo ©DRM Association 1998
My Receiving Setup
The receiver I am using is a Yaesu FRG-100/DRM supplied by SAT-Service Schneider in Germany. You can see the range of DRM™ products that they offer on this web page: SAT-Service Schneider DRM page. The FRG-100/DRM is fitted with a 12 kHz IF output and has bandwidth filter changes to receive DRM™ broadcasts. In my receiver I’ve had the wide AM filter bank used for DRM™ – this results in AM Wide being *really* wide when used for normal AM transmissions.
In December 2004 I also purchased a Digital World Traveller receiver from Coding Technologies. This is a small MW/SW/FM & DRM receiver that is designed for connection to a laptop or PC via USB.
In March 2007 I purchased a Morphy Richards DigitalRadio 27024, primarily for monitoring DAB test transmissions, but it also receives DRM quite well. I wrote a review of this radio for the April 2007 issue of the New Zealand DX Times magazine.
Thanks to RNZI, I have also had the use of a loaned SAT-Service Schneider DRT1 receiver, and a UniWave Di-Wave 100 receiver.
Additions to my DRM-capable receiver collection now include the CDNSE Newstar DR111 stand-alone consumer-grade receiver and the Elad FDM-S1 SDR.
Recently (2010-2013+) most of my DRM monitoring has been done from my holiday cottage at Marahau, Tasman Bay, using an un-modified AOR AR-7030, using the standard IF-out connector to feed into my computer.
My antenna is a 30 metre wire in the garden. This feeds my receiver through a JPS (now Timewave) ANC-4 noise reduction unit to help cut down some of the local noise from my PC (though it appears to make little, if any, difference to DRM reception quality).
I have also fitted SAT-Service Schneider DRM IF modules to my AOR AR-7030 and McKay Dymek DR33C receivers. Both perform well, but overall I find I use the Yaesu most.
I’m running the Dream and “DRM Software Radio” programs on a quad-core Intel i7 computer running 64-bit Windows 7 to decode and listen to the broadcasts.
Schedules
Current DRM Transmission Schedule
Reception in Europe
BBC on Mediumwave
The BBC has run a DRM trial on mediumwave 855 kHz from BBC Radio Devon in Plymouth. Thanks go to Frank G0GSR for providing this recording of their test loop:
RNZI to Europe
Early RNZI (now RNZ Pacific) broadcasts to Europe, via VT Merlin in the UK, can be found on >this page<.
Early Chinese Tests
Early Chinese tests to Europe, CRI 27.4 kbps stereo examples, recorded by listeners in Europe:
RTL Luxembourg 6095 kHz
Carsten Knütter from Germany has kindly allowed me to host these recordings of early test transmissions from RTL, Luxembourg, on 6095 kHz: