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What You Think

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StJohn
21 February 2020 - 1:44am
Anthony,
You have understood most of what I have written. FEC is used in virtually all digital communications systems.
In dish antennas the idea is to focus, just like light, the signal on the dish’s antenna. It makes it very directional. They are unsuitable for vehicles and boats unless a very sophisticated and expensive servo tracking system can keep the antenna pointed at the satellite whilst the vehicle/boat changes direction.
Those a ”shark fin’s” antenna is not only being used for the GPS vehicles on cars but also for SirusXM. The “shark fin’s” contains a small dipole antenna.
Journaline is an indexed text system, so the listener can select which message they wish to read. The Emergency Services in Australia are under the control at a state level of the Police as a co-ordinator.
As for PAL S errors, the lines of incorrect hue show in pairs on the screen because there is an odd number of lines ie 625 in a frame.
The Australian Broadcasting Control Board (the predecessor of the ACMA) not only banned PAL-S sets from import they also banned TVs which had half wave power rectifiers, they made them add either 1 or 2 more diodes because the electricity companies did not want residual DC currents flowing in the power lines causing electrolytic corrosion including on water pipes which were commonly used for earthing.
I do remember the chroma-lock system which was used to regenerate the burst. It had a 50:50 chance of getting the colour right. This may change whenever the channel was changed and even when the station changed sources. They were redundant after the commencement in March 1975 of official colour broadcasting. It allowed to gradually up grade the equipment nationally to have a simultaneous switch on of colour TV.
To make sure fully specified receivers are imported, all that has to happen is that the latest full ETSI specifications for DAB+/DRM are written into the existing Australian standard and that the ACMA /Department of Communications use its powers under the customs act to ban non-compliant receivers. Doing it this way makes sure the EWS system will work, by preventing the sale of incompatible receivers. It also stops retailers putting a premium profit on the better product.
St John.
Commercial Radio wants a nationwide roll out of DAB+ for emergencies
Aussiecam58
20 February 2020 - 6:55am
Regulation changes and networking has kill local radio. And loca identies. Pity we loose these iconic brands. One day local radio will be just relay stations SCA rebrands Redwave Media Western Australia stations
Anthony The Koala
19 February 2020 - 8:58pm
Dear Mr StJohn,
Thank you for your very informative responses I raised about a warning system and other issues related to DRM/DAB broadcasting. A few additional comments/remarks.

Forward error correction:
I agree with you that forward error correction is useless if a signal is undetectable especially if the sky is not clear, when it's raining or trying to receive under a structure or a wet tree. At that stage, the signal is 'over the cliff' and nothing can be decoded.

I also agree with you that forward error correction is useful where there is noise in the signal.

Forward error correction is also used in satellite DVB. So FEC cannot be useless in this application/context.

However, when it comes to satellite radio, if you meant that in addition to the environmental factors affecting the satellite signal and as a result that FEC being useless if the digital signal is "over the cliff" of reception would that be due to satellite radio's antenna gain having a low gain compared to a dish which is high gain?

For example, the car's radio antenna is a wire while a satellite DVB's antenna is a high gain parabola (dish)?

Who should be responsible for the dissemination of emergency information anywone or a specific officer:

When it comes to the issue of the dissemination of emergency information to a broadcaster's DRM message server (reference page 5. https://www.drm.org/wp-content/uploads/2014/07/DRM-EWF-Emergency-Warning-Overview-v2.pdf ) you mentioned that there's "...nothing to stop each emergency services to each have a computer with compatible software to create the data along with the affected area co-ordinates..."

I agree with that it does not matter who disseminates the information. The technology is 'dumb' as to who enters the data.

My concern is that you need a protocol with all 'contingencies' as to the supply of the information to the broadcaster's DRM system to ensure that (i) the information to the DRM's emergency reporting system is accurate and up-to-date and (ii) that there is no conflict of information advice between the authorities.

An example scenario:
The BOM issue a weather warning of strong winds, thunder, lightning, hail and torrential rain.

The warning may be forthcoming or come to pass. Should the BOM's warning go on the DRM's emergency system or should the SES and/or RFS issue the statement OR should the BOM, SES and RFS issue the warning and give advice?

Clarification of what you mean by a PAL-s receiver and banning receivers:
PAL refers to a standard of analogue TV. The benefit of PAL over NTSC is that the colour information is inverted on alternate lines of the picture raster. The S of PAL-S relied on the eye to cancel out any errors between the alternate lines.

The effect on relying on the eye to cancel errors in the error differences of the colour information was not perfect as the horizonal lines were still perceived. An electronic cancellation of the errors was chieved by alternate lines of colour information entering a delay line made of isopaustic glass. The electronic cancellation was achieved by adding the delayed signal to the undelayed signal. Effective vertical colour resolution was half the resolution of the luminance signal.

Note that my understanding is an oversimplified description. I have not included the interlacing of a raster comprising of two fields which complicates.

Ban receivers that are not fully specified and retailers?
Now in regards to the banning of receivers, I find it hard to believe that the Federal Government would ban a receiver that was not PAL-D, given that colour TVs were already in Australia before 1975. Can you elucidate (shed light) on banning of receivers.

Unless you mean that TV broadcasters were banned from transmitting in colour by the broadcaster's removal of the colour burst signal. Yet someone could 'cobble' a colour-lock circuit and receive the colour signal long before March 1975 and the test transmissions before March 1975.

In today's issue of whether banning DRM receivers which do not have full specificaions may well go against the "policy" of letting the markets decide the kinds of DRM receivers.

My belief is that many retailers do not understand the capabilities of the products they sell and they'll sell what is the 'cheapest'. It's like when digital TV's were on sale in the early 2000s and retailers did not understand the definition of FULL-HD (1080i). They were trying sell you that 780i was better than 1080i. I was not the Eskimo/Inuit that believed the line of the salesperson selling me frozen water.


Thank you,
Anthony of exciting Belfield
Commercial Radio wants a nationwide roll out of DAB+ for emergencies
Anthony The Koala
19 February 2020 - 8:03pm
Four issues about podcasts (i) the quality of the content of podcasts, (ii) overflowing of podcasts, (iii) having support networks in order to get an audience, (iv) not to take a podcast as settled or 'gospel'.

(1) The valuable content of podcasts is variable. In January 2020 there was a promotion on 2GB of a certain podcast starring a "traffic reporter" and a comedian.

I downloaded the half-hour podcast and listened to it. The podcast could have been reduced to five minutes and mention the relevant websites at the end.

(2) Following (1), the market may well be overflowing with podcasts. There are courses on the web including the University of Wollongong's mini course on how to produce a "production quality" podcast.

references:
https://universe.uow.edu.au/education/free-uow-short-course-the-power-of-podcasting-for-storytelling/
https://www.futurelearn.com/courses/podcasting/1

Even with high quality production values, how does one choose the 'wheat' from the 'chaff'. Put it another way, how does one's podcast stand out?

Thus at the beginning of (2) I stress the word 'overflowing' rather than 'saturated'. The barriers to entry are low. Any person who wants to educate or has an axe to grind or is an 'expert' or has an ego can make a podcast.

As a consequence of the overflowing number of podcasts, many podcast producers may well burn out within a few episodes especially if there is very little downloads. It may well be that the podcast producer may have to 'soldier on' and build other kinds of networks until the number of downloads increase.

(3) Having 'support' networks. By network I don't mean a broadcasting network but also include business, professional and community organisations. The list is not exhaustive. Such networks may well form the publicity base for the author's podcasts.

When it comes to broadcasting, the broadcaster has already a 'support' network of its listeners. The ABC comes to mind with their slogan "...you can download the latest podcast at...." or 2GB with podcasts of their show or interview segments. These podcasts are available for those who missed the actual broadcast.

(4) The podcasts are high quality in content and production values, but don't take the content of these podcasts as "gospel" or "settled knowledge".

Lily Serna, a mathematician and a co-presenter of SBS tv's "Letters And Numbers" produced a podcast series on what makes a genius. It was the usual questions of what makes a person a genius nature or nurture.
Issues discussed include whether intelligence is 'fixed' and Malcolm Gladwell's concept of 10000 hours of applied learning.

The issues should not be treated as settled because people may well develop at different rates and that the 10000 hour concept has either been misapplied or does not necessarily applied.

But then you cannot get a smooth podcast narrative by including all the nooks and crannies of what is settled and what is not and the debates surrounding the issues raised in the podcast.

Therefore don't take notice of all the content of a podcast as settled.

From my experience, I have a very dear friend whose late father was a teacher and housemaster at a prestigious and elite boys school. One of his students was the former PM The Hon. Malcolm Turnbull. My friend's late father also studied at Oxford and was learned also in the field of ancient history.

One of the issues raised in the podcast was on intelligence being fixed. Long before the existence of podcasts I asked my friend's father how to improve one's intelligence.

A few years before I met my friend's father, I was told that I was no good for university and cannot imrprove my 'intelligence' by the school counsellor who was in cahoots with the year 12 coordinator who later self-harmed (if that issue affects you call Lifeline on 13-11-14 and/or an evidence-based AHPRA practitioner).

I asked my friend's father how to improve one's intelligence and he said to keep on reading widely. It worked for me and I have a law degree from UNSW (amongst others).

I also interviewed the famous US educator Jane Elliot on 2SER-fm radio. She said that one should not accept what teachers or authority figures define you as if one is from a low socio-economic status and in a rut.

My life story is not as simple as this, though I cannot say that what worked for me applies to you.

Irrespective of this I go to the original point about the the content of podcasts should not necessarily be taken as settled or 'gospel'.

References:
https://www.lilyserna.com/blog/2018/4/21/decoding-genius
https://podcasts.apple.com/il/podcast/decoding-genius/id1167164216?mt=2

Conclusions:
Deloitte may well be correct that podcasts may take over radio broadcasts. The quality of the content and broadcast quality of a applies to both broadcasts and podcasts.

Even if one can produce a high quality podcast, there is an overflow of podcasts on the network. To get noticed needs a support network such as business or professional groups or from a radio broadcaster's audience.

Similarly even if the podcast is well-produced and contains content, don't take the content of the podcast as settled or 'gospel' especially if the issues are debatable.

Thank you
Anthony of opinionated Belfield
Deloitte suggests podcasting growth ahead
StJohn
19 February 2020 - 1:10pm
The system standards for DAB+ and DRM are free. Manufacturers have to pay for the firmware and hardware patents in common with the rest of industry unless you develop your own.
Fraunhofer is a German Technical University which sells its intellectual property. They not only developed the Journaline system but also the audio compression systems used in all digital radio, TV and the internet. ie xHE AAC, AAC V2, MP4...

Xperi HD radio also charges a licence fee to broadcasters for using their standard as well as a bounty on each HD radio manufactured.
Commercial Radio wants a nationwide roll out of DAB+ for emergencies
StJohn
19 February 2020 - 1:04pm
Anthony,
The only satellite radio broadcasting system in the world is SirusXM which covers a potential audience of over 300 million it doesn’t make a lot of money http://investor.siriusxm.com/investor-overview/default.aspx#news and check out their package prices. (Multiply by 1.5 for AuD) You will note that users have to buy a car which contains the satellite receiver and they don’t tell you that the signal disappears under bridges in interchanges and in the canyons of cities. They have additional prices for outside cars because the signal is delivered by the mobile phone or internet systems.
Forward Error Correction is useless if the signal is undetectable such as inside buildings under wet trees, heavy rain. It is only useful to cover up noise and interference and will work up to the digital cliff, making reception more reliable at the coverage edge then nothing.
For black spots we use off air repeaters which receive the signal, filter and amplify it and retransmit an identical stronger signal. This means the receiver does not have to change to and from L channels as you move around.
“Journaline” transmits an index and then the content so no interactivity is required back to the broadcaster. The listener selects a message from the index and the receiver recovers it from memory.
DAB+/DRM can receive hyperlinks so if the receiver is part of a mobile phone or wireless speaker this link can then be used to go to the specified website.
I have never seen a DAB+ radio which cannot display a line of scrolling text which is extremely limited in terms of an EWS. All DRM radios have bigger screens which can show slideshow and Journaline. Infortainment systems in cars have a bigger screen. What we need is for the importers of radios and cars/trucks to only sell fully specified DAB+/DRM receivers. If the current DAB+ receivers are banned from import the price of these fully specified receivers will be much cheaper. The Government at the start of colour TV banned simple PAL receiver and only allowed full PAL which meant that horizontal colour bands in the picture were never seen. Retailers could not upsell the better model.
The EWS system only has one transmitter radiating the EWS data. All other broadcasters radiate a EWS code and the Alternate Frequency System tells the receiver where to tune to obtain the data. It also contains the latitude and longitude dimensions of the area affected by the emergency so that all other listeners are unaffected.
Grant Broadcasters, Darwin trialled EWS where the computers in the Emergency Services computers produced the data transmitted by the DAB+ transmitter. There is nothing to stop each emergency services to each have a computer with compatible software to create the data along with the affected area co-ordinates and all the broadcaster has to do is to cue the messages in order of receival. The Emergency services will also have to order the deletion of messages which are no longer relevant.
Commercial Radio wants a nationwide roll out of DAB+ for emergencies
StJohn
19 February 2020 - 11:55am
Perhaps this indicates the poor quality of programming on radio, which could increase if they broadcast the podcasts and also leave them available for later replay. This would increase the popularity of these productions. Deloitte suggests podcasting growth ahead
Anthony The Koala
18 February 2020 - 1:37am
Dear Mr StJohn,
Thank you for your very informative reply on the feasibility of the L-Band. It is very instructive that a paper produced by the ABC in 2010 at https://about.abc.net.au/wp-content/uploads/2012/06/ABCSubmissionTechnologiesForRegionalDigitalRadioDec2010.pdf.

While the signal may well be very weak from a satellite 36000km above the Earth's surface, one would think that the forward error correction utilized in satellite DVB would correct any errors due to propagation and any intermittent attenuation of the signal from the satellite transmitter(s).

Nevertheless the ABC report on page 8, 2nd paragraph, mentions the unsuccessful trials of DAB in the L-Band in Germany and Canada because of coverage reasons and lack of consumer demand ("acceptance"). The report did not elaborate on the problems of "coverage". Though you did mention that L-band reception must "...see the sky..." and its signal is attenuated by rain and cannot penetrate trees.

However the ABC report page 8, third paragraph did mention that L-Band transmissions may be used to fill in for black spots in the future.

You mentioned about the dynamic text "journaline" which is a hierarchical system of interactive textual information, like news, or graphics. The interactive aspect of the information does not mean a handshaking/protocol and user information is returned from the user's receiver to the radio station.

Journaline can be implemented in DRM and DAB transmissions and implementers of the technology must pay a licence fee to Fraunhofer, https://www.iis.fraunhofer.de/en/ff/amm/broadcast-streaming/journaline.html.

Although section 6 of the Broadcast Services Act no.95 (Cth) as at 12 December 2019 https://www.legislation.gov.au/Details/C2019C00338, section 6 definitions "digital program enhancement content", and "datacasting service" mentions the use of text or a combination of text and graphics.

There is no limitation to the definition of "text" in both "digital program enhancement content" and "datacasting service" though the latter transmission of text requires a separate transmitting licence and the user having "equipment appropriate to receive the datacast".

In either case of transmissoin of "text", there appears to be no limitation to the kind of text whether static or dynamic for a broadcast or datacast. If there is an issue, then the Minister can clarify this by issuing a legislative instrument pursuant to s6 "digital program enhancement content", subsection (c).

Emergency warning system.
The problem with transmitting emergency information under the DAB system is that "scrolling text" is not always activated in the DAB receiver. I've raised this issue elsewhere on this site that the user may want to have the time and date displayed and may not be viewing the scrolling text. There is no 'wake up' facility should the DAB scrolling text contain emergency information.

In spite of DAB's limitation not to wake up the radio, a person listening to a radio station could be informated by the presenter to switch the user's radio to scrolling text for emergency information.

A further issue with DAB's scrolling text, is that most DAB receivers are have a display of one to two lines and the scroll speed cannot be adjusted for fast or slow scrolling.

In the matter of DRM implementing the EWF ('Emergency Warning Functionality'), a policy/protocol must be established between the emergency authorities and the National and/or commercial broadcaster in co-ordinating to enable the dissemination of emergency information from the broadcaster's server, page 5. https://www.drm.org/wp-content/uploads/2014/07/DRM-EWF-Emergency-Warning-Overview-v2.pdf.

A protocol is required to disseminate the emergency warning to the broadcaster whether through a DAB scrolling text or DRM's EWF.

During the conflagration of the East Coast of Australia, there was the issue of who should co-ordinate the emergency, whether by Federal Government's Military Forces (Army, Air Force and Navy) or by the various State's RFS ('Rural Fire Service') or SES ('State Emergency Service'). I mention the SES in case the disaster is a cyclone. Then when it comes to the Weather through the BOM ('Bureau of Meteorology') or a geological event through Geoscience Australia.

Whoever coordinates the emergency, a protocol must be established as to the delegation of the warning messages to the broadcaster.

In end, as Mr StJohn said, regardless of a DRM and/or DAB broadcast requires receivers to be , "...fully spec'ed DAB+/DRM receivers which can operate from 500 kHz to 230 MHz. I would also add that the receivers must have larger displays especially avoiding the slow scrolling time under a one or two line display.

Thank you,
Anthony of researching Belfield
Commercial Radio wants a nationwide roll out of DAB+ for emergencies

18 February 2020 - 12:41am
Whoops, their timing is a bit off - she was born on 25th March 1942, not 21st February! PBS FM may have to change its tribute for another month! PBS 106.7FM pays respect to Aretha
StJohn
17 February 2020 - 7:12pm
JJcoolaus,
HD radio digital signal is 1 % of the power of the AM broadcast and as a result has a small coverage area. You are right about DAB+ coverage area. A better option is to use DRM in the 47 - 68 MHz range to give 18 programs per transmitter mounted on the TV towers. DRM can also be used by the community broadcasters who missed out. There are only 8 DAB+ transmission channels where as for the above DRM there are 168 channels available. It is not economic to provide mobile coverage for every km of road in Australia and the area in between. High powered High Frequency DRM can do this from a single site in the centre of Australia.

David,
5G in its high speed mode needs a repeater every 900 m, it won't go through walls, wet tree leaves etc.
The cheapest way to distribute program to large numbers of people is broadcast which is one way not 2 way for phones/internet. DAB+ is ideal for high population densities where we use it and DRM for any population density because it can cover much larger areas at lower cost and is suited to transmitting small numbers of programs where as DAB+ is designed for large numbers of programs.
Anthony
Geo-stationary satellites are at 36,000 km above earth and the signal is weak when it is spread all over Australia.
There are no L band broadcasts anymore. The Canadians used it for DAB and it was a disaster. Poor coverage terrestrially. It was trialed in Australia, but the antenna must see the sky, Thus it won't work in side or through trees or in heavy rain. Satellite capacity is more expensive and you need a program for each of 5 time zones.
All DRM radios can show much more than a single line of scrolling text. Check out Journaline and slideshow.
High powered High Frequency DRM is a cost effective way of covering the whole country which can include the EWS. In addition the EWS signal can also be radiated by the ABC/SBS DAB+ transmitters, however nearly all non automotive receivers can only display one line of scrolling text. What we need is for only fully spec'ed DAB+/DRM receivers which can operate from 500 kHz to 230 MHz.
Commercial Radio wants a nationwide roll out of DAB+ for emergencies

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