Digital Radio Technologies
This website started life as a link to my web pages
about DRM™ digital
shortwave radio reception in New Zealand.
With the start of DAB trial broadcasts here in New Zealand
it has been expanded to cover that form of digital broadcasting.
The current Kordia DAB pilot multiplex contains two streams of Radio
New Zealand's RNZ Concert service, one a 192 kbps MP2 (DAB)
stream, the other a 64 kbps AAC+ (DAB+) stream.
Here are examples of both streams, recorded off a Blik DAB+/FM/Internet Revo RadioStation,
and encoded using FLAC lossless
These longer recordings are available:
DAB pilot transmissions have started in Auckland & Wellington, New Zealand.
These are being carried out by Kordia (formerly BCL). Initial tests
are using MPEG-1 Audio Layer II (MP2) encoding, but any roll-out is likely to use
AAC+ as in Australia. The MED SpectrumOnline
website indicates that the Wellington pilot is on 192.352 MHz (NZ DAB block
6C), with 23.0 dBW power in the Wellington CBD. It indicates that
the Auckland trial is on 227.36 MHz (NZ DAB block 11C), with 27.0 dBW power
from a transmitter in Waiatarua (Waitakere area, West Auckland).
My own receiver indicates that the Wellington pilot is on block 7C rather
than 6C due to NZ's different numbering scheme.
After some initial teething troubles I got very good
reception from my Lambton Quay office (subject to being away from
the general noise of PCs etc). Here are some samples, recorded
during April 2007. These files are straight off the SDRAM recorder
card in the Morphy Richards so are at the same bit rate as the DAB
audio stream. You will need a broadband connection to listen without
Update June 25, 2014
The Wellington mixed DAB/DAB+ pilot mux is still on air in Wellington,
on channel 7C, 192.352 MHz, carrying the following services:
Update August 2014
The transmitter for the Wellington mux has been moved to Mt Kaukau, providing much
wider coverage around Wellington.
Update February 2017
The Wellington mux is still on-air, with the same content.
Update October 2017
The Wellington mux is still on-air, with the same content. The signal seems
stronger on my little Sangean receiver.
The Sangean DPR-65 is typical of the portable DAB+ receivers now available (mid 2014)
from major electronics retailers in Australia, such as JB HiFi.
This receiver works
perfectly with the Kordia pilot in New Zealand.
The Morphy Richards DAB/DRM/LW/MW/SW DigitalRadio 27024 receiver was
available from various sources in Europe. This multi-standard
consumer level radio also features an SD recording card.
I wrote a review of this radio for
the April 2007 issue of the
New Zealand DX Times magazine.
- Digital Radio DR - common branding for all digital radio technologies.
- DRM™ - "Digital Radio Mondiale" - long, medium & shortwave bands worldwide
- IBOC - "In Band On Channel" - currently North American AM band
- DAB - "Digital Audio Broadcasting" - multiplexed programs in various VHF & UHF ranges
- WorldSpace - subscription service for Africa, Asia, the Americas
SIRIUS - North American
subscription radio services
- HamDream - Digital Transmission of Voice and Data over radio with 2.3 to 2.5 kHz bandwidth.
I welcome any corrections and additional relevant links.
Chris Mackerell - firstname.lastname@example.org