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Investing in a DAB radio company
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MK14:

--- Quote from: coppice on May 09, 2020, 03:00:21 pm ---
--- Quote from: MK14 on May 09, 2020, 02:52:42 pm ---But, I think I have heard reviews and things say, the dab radio sound quality is not very good. Especially not compared to the much later, and better standards, which emerged, in Europe.

--- End quote ---
There are two huge weaknesses in the original DAB spec. They rushed the spec out, even though it was obviously going to take quite a long time to move in the market. This meant they had to use a crappy codec. because the first of the decent ones, like MP3, were still in development. By the time DAB product development had really got anywhere, MP3 was available. They made some funky choices in the coding, so there are situations where a weak signal causes a modest bit error rate, but this results in some very unpleasant noises.

I think most of the DAB radios in the UK are DAB+ designs, which fix these problems. However, because some early DAB only radios are still around, the transmission side has not been changed.

--- End quote ---

That is so sad and crazy.

When the UK, moved to colour TV (from memory, around 1966, PAL, BBC2, the new second! UK channel). They were very clever in the signals design. It maintained compatibility with 625 line black and white signal TVs, and yet added the 2 extra colour signals, so that full colour TV could be shown. From the same TV signal.

I.e. It could be used for black and white (625 line) TVs, or on (much more expensive and very rare at the time), colour 625 line (PAL) TVs.

If my memory is playing up (there was eventually a third TV station, ITV), and there were 405 line (old standard) Tvs, still floating about, for many years, after that. Until the signal (405, great reception quality, with simple Aerials, usually all valve/tube sets) was eventually turned off in the 1980's.
N.B. All above from memory, so could be out by a bit.

I.e. Dab, should have been able to have (include the option for) later/future standards, which still kept the old radios working. This should have been thought of, when dab was originally conceived.
Analogy: Otherwise, we would still be limited to a maximum of 4K of Ram on microprocessors (Intel 4004), and maybe 640K of ram, on PCs.
Bicurico:

--- Quote ---I.e. Dab, should have been able to later standards, which still kept the old radios working. This should have been thought of, when dab was originally conceived.
Analogy: Otherwise, we would still be limited to a maximum of 4K of Ram on microprocessors (Intel 4004), and maybe 640K of ram, on PCs.
--- End quote ---

DAB/DAB+ were developed to produce a new market and respective demand. Those implementing it could not care less about existing receivers! Interestingly this is the reason it failed completely.

The same happend when analog TV was replaced with DVB-T. You would expect one single norm for the whole world or at least the EU.

But no: in a short period of time we got two modulations (DVB-T and DVB-T2).

These carry different codecs: MPEG2 or MPEG4, MP3 or AAC. In any combination!

This means that a DVB-T receiver sold in Spain may not work in Portugal...

In Germany they introduced DVB-T with MPEG2/MP3 but after only a few years they replaced it by DVB-T2. Imagine the amount of incompatible TV's which were brand new! And an even higher amount of receivers that are obsolete in 1-4 years...

Oh, and there was DVB-H, too... Meant to provide audio and video to moving cars. It died because of DAB/DAB+, if I correctly remember.

With all this said and staying on topic, the only reason to invest in a company in this field is if you can lobby your exclusive right to produce a compbination of demodulator and codec that allows you to own the market for a given period of time (ahead of competitors) and with a market created by a forced shutdown.

Regards,
Vitor
MK14:

--- Quote from: Bicurico on May 09, 2020, 03:23:03 pm ---DAB/DAB+ were developed to produce a new market and respective demand. Those implementing it could not care less about existing receivers! Interestingly this is the reason it failed completely.

The same happend when analog TV was replaced with DVB-T. You would expect one single norm for the whole world or at least the EU.

But no: in a short period of time we got two modulations (DVB-T and DVB-T2).

These carry different codecs: MPEG2 or MPEG4, MP3 or AAC. In any combination!

This means that a DVB-T receiver sold in Spain may not work in Portugal...

In Germany they introduced DVB-T with MPEG2/MP3 but after only a few years they replaced it by DVB-T2. Imagine the amount of incompatible TV's which were brand new! And an even higher amount of receivers that are obsolete in 1-4 years...

Oh, and there was DVB-H, too... Meant to provide audio and video to moving cars. It died because of DAB/DAB+, if I correctly remember.

Regards,
Vitor

--- End quote ---

This concept, seems to happen, lots of the time.
Driving on the left vs right.
VHS vs Betamax (vs V2000/Video2000)
Blu-ray vs HD DVD
DVD-R vs DVD+R
Big-endian vs Little-endian
Metres/Kilometres vs Yards/Feet/Miles/Inches
UK Gallons vs US Gallons (This always gets me, how on earth can they be different sizes, but the same NAME, crazy).
Because of Brexit, I suspect there will be more to add to this list.
Mains voltages, (50/60Hz) frequencies, max currents, plug/socket types/styles, are not exactly standardised on a world-wide basis.
coppice:

--- Quote from: MK14 on May 09, 2020, 03:14:49 pm ---I.e. Dab, should have been able to have (include the option for) later/future standards, which still kept the old radios working. This should have been thought of, when dab was originally conceived.
Analogy: Otherwise, we would still be limited to a maximum of 4K of Ram on microprocessors (Intel 4004), and maybe 640K of ram, on PCs.

--- End quote ---
Just like DVB-T, DAB does provide for upgrades. The channel ID, codecs, bit rate, and other parameters are send in the bit stream, so these can be changed at any time, and the receiver knows what it is receiving. However, an old receiver can't make sense of newer features. As with DVB-T, DAB could be broadcast concurrently in older and newer forms, with the receivers able to select the stream which best suits them. The BBC and ITV TV channels have chosen to do this. The radio channels haven't.

Comparision witth analogue TV is similar. 405 line TV couldn't be made compatible with 625 line, so they arranged parallel broadcasts of the two standards (although in limited amounts. Most people had to wait for colour broadcasts to start in order to get the parallel higher resolution broadcast (which was a HHHUUUGGGEEE improvement) on their B/W TVs). Those old analogue systems didn't tell the receiver what it was receiving, so selection was entirely manual. It was a natural thing to make colour transmissions compatible with black and white, so that is what they did, and the 625 line B/W transmissions could migrate seamlessly to a combined B/W and colour signal. Another compatibility choice was with FM radio. There was nothing particularly natural about the way they added stereo to FM transmissions, but there was a strong desire to make a single transmission compatible with both mono and stereo receivers. So, they cooked up the sum and difference approach, and merged the 2 signals onto a single carrier, using a sub-carrier. Selection was fully automatic there, as a stereo capable receiver just has to detect the sub-carrier.

History is full of upgrades where the choice has to be made between running parallel systems vs a single merged compatible system. The choices made have mostly made sense.
richard.cs:

--- Quote from: coppice on May 09, 2020, 02:46:04 pm ---Millions of people in the UK use DAB. but in their cars. not their homes. People don't use any kind of radio in their homes much these days. I took part in a survey about radio usage last year, and the lady questioning me said the majority of reported radio usage is now in cars, with some growth in using the BBC's sounds app at home.

--- End quote ---

And yet you can still buy a new car and not get a DAB radio. Yes these are now a minority but they will be on the road for the next 15 years or so:

https://radiotoday.co.uk/2020/01/record-year-for-dab-radio-as-standard-in-new-vehicles/

--- Quote ---
DAB in new car registrations rose to a record 95% of all new cars in Q4 2019, while DAB in new commercial vehicles increased to a record of over 64%.

--- End quote ---
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