213 replies to this topic

[chris jowett]

alanh, on May 2 2006, 12:33 AM, said:

There will be two types Digital Radio
DMB (Digital Multimedia Broadcasting)

Forgive my ignorance, but where do the 'radio' stations broadcast on DVB (eg Dig Jazz) fit in?
Given that we'll all need to have DVB by 2008 or whatever, wouldn't broadcasting digital radio that way make sense?
The basic no-brand SD DVB boxes are extremely cheap.
The quality sounds very good to me. I recieve Dig Jazz on 201 from Sydney at about 85% signal strength, which is not bad for 150km away. According to the DAB map I'd have buckley's of getting any of the DAB broadcasts even if I did fork out the small fortune for a tuner.

[alanh]

chris jowett,
Dig etc are taking some of the capacity of the TV signal for sound only channels. The transmissions are on any channel from channel 6 - 69. You must use a STB.
DMB is designed for portable receivers just like radios now, but with an optional screen. The transmissions are optimised for reception in the presence of reflected signals which is typical of car radios and personal receivers. You get 4 separate transmitted channels in the space of a TV channel. Each DMB channel can carry at least 5 programs with some pictures added. So this is 20 programs in the space where you may get a maximum of 2 if piggybacked on TV.

The map you are looking at is using a 5 kW transmitter, where as the TV channel you are using is 50 kW.

AlanH

[chris jowett]

alanh, on Feb 1 2007, 07:00 PM, said:

chris jowett,
Dig etc are taking some of the capacity of the TV signal for sound only channels. The transmissions are on any channel from channel 6 - 69. You must use a STB.
DMB is designed for portable receivers just like radios now, but with an optional screen. The transmissions are optimised for reception in the presence of reflected signals which is typical of car radios and personal receivers. You get 4 separate transmitted channels in the space of a TV channel. Each DMB channel can carry at least 5 programs with some pictures added. So this is 20 programs in the space where you may get a maximum of 2 if piggybacked on TV.

The map you are looking at is using a 5 kW transmitter, where as the TV channel you are using is 50 kW.

AlanH

Oh.
So this is big, like when FM was first coming in and 2JJ got another J (yeah I'm that old).
I imagine it will be some time before I'll get a new car radio, but on the other hand DVD players are $39 at ALDI and VHS tapes are starting to vanish from the shelves.
In the meantime, while the government, the broadcasters, the manufacturers, other countries et al are determining what we get, do you think they'll add any DVB audio stations?
Finally what range/power will the eventual standard have? I get FM and DVB 150km from Sydney and would expect at least the same.

[alanh]

Chris,
Since FM and DMB band 3 are both VHF the range will probably be similar. However the inital proposal on 1st Jan 2009 is Brisbane, Gold Coast, Newcastle, Sydney, Melbourne, Geelong, Hobart, Adelaide and Perth.

AlanH

[...]

reported

[tamago_otoko]

This sounds exciting. Just thinking tho, with distant stations. It would probably be very difficult to listen to a distant station while moving (eg. car, walkman etc.) with digital. However, I would think that with a stationary set up like a household radio, we could be listening to perfect quality radio from all over the place provided you can find a spot that has enough strength to maintain a steady signal. That sounds fun. Just the whole idea of car radios patching out and missing whole bits of transmission doesn't excite me. Gimme a bit of analogue static anyday over that.

Don't know about everyone else, but I am kinda sad that the whole analogue age will be a thing of the past in the not-too-distant future.

[GlennP]

I've found some more detailed info on the DRM trials from Wollongong & the HD Radio trials from Wagga Wagga, being done by  TJH Systems Pty Ltd.
Click on the links below to find out more:

DRM Trial info.
HD Radio trial info.

Cheers
GlennP.

[lizclinton]

I would have thought that broadcasters needed to be licenced to use the ibiquity system here in Australia. And why would they bother when we are going to use eureka 147 anyway.

Edited by lizclinton, 17 September 2007 - 04:00 PM.

[alanh]

Liz,
The site states that they have a licence  which will be a temporary experimental licence.

The objective here is to use existing FM transmitters, however a low data rate is used and the digital signal is on the outside edges of their channel.

Another option is DRM+ which is being standardised for upto 120 MHz.

AlanH

[GlennP]

Radio 2ME Sydney isn't waiting for the government to make decisions on Digital radio they've already taken the jump & started broadcasting digital using DRM.

Taken from the 2ME web site:

Radio 2ME has started broadcasting of DRM Digital Radio in Sydney. You can now listen to Radio 2ME in crystal clear DRM Digital! Soon, 2ME will be broadcast in stereo on this medium for even more spectacular DRM digital sound quality.

DRM Digital Radios will be progressively introduced and will become increasingly available over the coming months.

2ME is a Arabic language Commercial station broadcasting on AM 1638kHz in Sydney & other state capitals.

Cheers
GlennP.

[alanh]

GlennP
Good on them. Notice they must have a narrowcasting licence because their frequency is greater than 1602 kHz!

AlanH

[big mick000]

umm... when DAB starts @ mount Baranduda, upper murray, will it kill or interfere with the DVB-T also on band III, at the moment, i have a fracarro antenna x 2 with a MHV44HLG, and the reception just holds on to 0 BER, but most of the time, it is just below regular pixelation, so i feel, if there were to be any more carriers on the same namd, my digital would be killed, as at the moment it is struggling with some interference from corryong. will it alternatively be on band II? like FM? vertical, or horizontal?

[:)]

GlennP, on Oct 28 2007, 08:51 AM, said:

Radio 2ME Sydney isn't waiting for the government to make decisions on Digital radio they've already taken the jump & started broadcasting digital using DRM.

Taken from the 2ME web site:

Radio 2ME has started broadcasting of DRM Digital Radio in Sydney. You can now listen to Radio 2ME in crystal clear DRM Digital! Soon, 2ME will be broadcast in stereo on this medium for even more spectacular DRM digital sound quality.

DRM Digital Radios will be progressively introduced and will become increasingly available over the coming months.

2ME is a Arabic language Commercial station broadcasting on AM 1638kHz in Sydney & other state capitals.

Cheers
GlennP.

a bit silly in my opinion if the government hasnt as yet made a decision. I havent seen one thing from the government re DRM. I remember the digital radio bill allowing the trials to look for solutions for the regional area but nothing to state DRM would be the go.

It seems a few very keen to pushing all sorts of different digital technology regardless of the government making a deicision or not and especially since different tecnologies trials still go on bizare !

[alanh]

alebonau & GlennP,

You will notice that 1638kHz is not within the AM broadcast band in Australia, so Narrowcasting rules apply not broadcasting rules. Regardless of this the ACMA must have approved a test licence otherwise its an illegal transmission.

The other thing to notice is that DAB, DAB+, DRM and DRM+ are all international standards now, so the only real testing required is the coverage under various geographic and atmospheric conditions.

AlanH

[:)]

alanh, on Jan 26 2008, 01:20 AM, said:

alebonau & GlennP,

You will notice that 1638kHz is not within the AM broadcast band in Australia, so Narrowcasting rules apply not broadcasting rules. Regardless of this the ACMA must have approved a test licence otherwise its an illegal transmission.

The other thing to notice is that DAB, DAB+, DRM and DRM+ are all international standards now, so the only real testing required is the coverage under various geographic and atmospheric conditions.

AlanH

so that would just be a trial then just like hte dab and other drm trials going on ?

DRM+ ? thats a new one ! by the time the government decide on a standard we'll end up with 3+ !    

bring on 2009 I say ! the government said we'd have digital radio by then. but given theyre still fanning about with trials of the different formats still, dont like our chances ! maybe they meant end 2009 ! hehe

[alanh]

alebonau,
Different horses for different courses.
DAB+ is best suited to high density populations where 9 programs will be used per transmitter. However being VHF it will not cover country areas without lots of repeaters. This is where DRM comes in because it can use MF and HF bands. So  HF DRM could cover the whole of Australia with one transmitter.
This is like we have AM and FM now.

DRM works up to the top end of the HF(Short Wave bands) where as DRM+ adds 30-88 MHz meaning it can be used in the vacated TV channels 0 - 2.

What DAB+ and DRM have in common is the same compression system where as DAB uses MPEG1

AlanH

[:)]

alanh, on Jan 27 2008, 11:09 AM, said:

alebonau,
Different horses for different courses.
DAB+ is best suited to high density populations where 9 programs will be used per transmitter. However being VHF it will not cover country areas without lots of repeaters. This is where DRM comes in because it can use MF and HF bands. So  HF DRM could cover the whole of Australia with one transmitter.
This is like we have AM and FM now.

DRM works up to the top end of the HF(Short Wave bands) where as DRM+ adds 30-88 MHz meaning it can be used in the vacated TV channels 0 - 2.

What DAB+ and DRM have in common is the same compression system where as DAB uses MPEG1

AlanH

appreciate alan, however its still just a trial like all the other trials going on of the different technologies like the one for DAB which is still going on in melb. the government in the digital radio bill has never said anythign re drm as a standard just allowing the search for other technologies for the bush and regional areas where dab might be unsuitable. wonder when things will move past the trials phase and the government give the ok as to what technologys gets used for digital around australia. probably a long way off that as theyve hardly covered a lot of geographys with their trials of the different technologies. just keeps dragging on..a bit like the dtv switchover though atleast there they got somethign off the ground with digital take up even if the switchover has still not happened all these years past and a changeoever date that jsut keeps getting bumped...

[Skid_MacMarx]

Quote

The other thing to notice is that DAB, DAB+, DRM and DRM+ are all international standards now, so the only real testing required is the coverage under various geographic and atmospheric conditions.

Surely it wouldn't be too much to expect that CE manufacturers to introduces receivers, which support all of the above digital modulation techniques and VHF FM

[:)]

Skid_MacMarx, on Jan 27 2008, 05:00 PM, said:

[/b]
Surely it wouldn't be too much to expect that CE manufacturers to introduces receivers, which support all of the above digital modulation techniques and VHF FM

yeah I dont think there'd be one receiver available here to do all those skid. I know the likes of dab+'s existence was only acknowledged early last year but I guess a year isnt too long to expect manufacturers to bring out receivers here to pick up all those transmissons.

[alanh]

alebonau,
About the middle of last year the ACMA reserved many HF or short wave bands for DRM. As far as the AM band goes they have to find allocations within the existing bands.

AlanH

[:)]

alanh, on Jan 28 2008, 12:05 AM, said:

alebonau,
About the middle of last year the ACMA reserved many HF or short wave bands for DRM. As far as the AM band goes they have to find allocations within the existing bands.

AlanH

didnt answer skids question, and 2009 is only 11 months away ...

Skid_MacMarx, on Jan 27 2008, 05:00 PM, said:

[/b]
Surely it wouldn't be too much to expect that CE manufacturers to introduces receivers, which support all of the above digital modulation techniques and VHF FM

[alanh]

Skid,
There is a manufacturer "Radioscape" which makes a module which receives DAB, DRM, AM and FM stereo, which the receiver makers are using. These radios are available overseas now. However the standard for DAB+ and DRM + are new hence, the major manufacturers are promising the type of receiver you mention this year.

AlanH

[mtv]

It was announced in March 2007, that Australian commercial stations are adopting the DAB+ standard:

Quote

14-Mar-07  AUSTRALIA TO USE DAB+ FOR DIGITAL RADIO ROLLOUT

Commercial radio broadcasters today announced they will adopt the new DAB+ standard for the implementation of digital radio in Australia.  DAB+ is the new standard for the Eureka 147 platform using advanced audio codec (AAC+).  It was officially approved by international standards body ETSI in February.

The chief executive officer of industry body Commercial Radio Australia, Joan Warner, said DAB+ would provide a better digital radio experience for listeners.

“We have been very active in supporting the international development of DAB+ because it means Australia will be able to adopt the latest, most spectrum efficient technology in the world for the roll out of our digital radio services,” Ms Warner said.

DAB+ is two to three times more efficient than the original Eureka 147 standard which uses the MPEG Audio Layer II coding.  This means radio stations will have more choice in how they use their allocated bandwidth.

“DAB+ offers much more efficient compression, which means more stations can be broadcast on a multiplex, resulting in lower per station transmission costs,” Ms Warner said.

“It also means each broadcaster will now have the ability to deliver either superior audio quality, split their signal to offer two or three audio channels, or broadcast a combination of better than FM quality sound plus lots of associated data such as text or images.  Whichever way stations choose to implement digital radio, the result will be a better service for listeners and advertisers.”

Ms Warner said commercial radio was continuing to work with the ABC and SBS Radio to test the DAB+ standard in Australia and to ensure there will be no transmission or other technical issues.  The industry is also working with overseas broadcasters and receiver and chip manufacturers on the development of new DAB+ receivers.

DAB+ services and receivers are expected to be rolled out in a number of countries where digital radio is currently in trial phase, which potentially includes the Netherlands, Malta, New Zealand, India and China.

“We want to encourage the availability of a wide range of affordable digital radio receivers with new features such as picture capability,” Ms Warner said.  “Some leading manufacturers have told us that they expect to start shipping DAB+ radios later this year.”The Federal Government is currently drafting digital radio legislation and has set a launch date of 1 January 2009 for the launch of digital radio services in Sydney, Melbourne, Brisbane, Adelaide, Perth and Hobart.  The commercial radio industry is planning for a phased rollout across the rest of Australia to follow.

source

[:)]

mtv, on Jan 28 2008, 02:31 PM, said:

It was announced in March 2007, that Australian commercial stations are adopting the DAB+ standard:
source

think we remember reading that back in march last year  

but almost a year later...

wonder where are the DAB+ receivers..wonder when commercial radio stations are goign to start broadcasting.

so far all we have is trials still going on evaluating the different technologies. including in melbourne where the DAB radio trail is still going on...

also the government has been very quiet on the topic, after the passing of the digital radio bill talking about dab for australia from 2009 and evaluation of other technologies for regional areas theyve been very quiet on the topic. atleast with dtv the new government made an undertaking to speed things along, however with digital radio maybe not something theyre not to concerned with and not really even on their radar !

[alanh]

alebonau,
The Sydney trial was organised effectively and paid for by Commercial Radio Australia. This is an association for all commercial radio stations. The Melbourne trial is by Broadcast Australia.

Since Commercial Radio Australia has already made up its mind, why are they continuing trials? Perhaps they have left the transmitter on because they still have the test licence and it doesn't cost much to run?

AlanH