BBC Shelve FM Switch Off.

I bet I'm not the only person who doesn't have a "smart phone"

You bet correctly, I don't even have a portable 'phone, the only one I have is so posh it's tied to the house with some wire.

[ThePillenwerfer]

I'm listening to 6 Music via FreeView at present, which is what I mostly use. I listen to Radio 2 and Radio 4 on FM but probably more via the internet at times that suit me rather than the schedulers. MW is a dead duck as there's nothing on it I want to hear, and RFI is an additional problem.

Contrary to most people DAB quality is better for me as I've never been able to get a usable VHF stereo signal.

For all that I'd be sorry to see FM go it wouldn't be a great inconvenience in practical terms. What may be a bigger concern would be what happened to the wave-band. If it were left largely clear it would open up possibilities of pantry transmitters with better audio quality than AM ones.

[stevehertz]

I started a post about DAB and FM, what, a year or so ago, maybe more. There was lots of input and - to me at least - a few clarifications and myth busting as a result.

Firstly, I'm an FM man through and through. I also like AM, but there's very few stations out there where I am so the choice is limited - basically R5Live. Re DAB/DAB+, there's lots of choice including a dedicated jazz channel that I like, curiously called 'Jazz FM'. Yeah, I used to listen to it when it was FM.

The majority of FM stations are broadcasting rubbish, that's content and quality. They're applying limiting like nobody's business and the sound is just awful, not to mention the seemingly endless ads that once heard jar like a blow the head with a baseball bat. And DAB broadcasts are generally in the same boat. But saying that, DAB+ is capable of providing very high quality, it's down to the station as to how it is processed and broadcast for us to 'enjoy'. The bottom line is, when considering the received quality of FM and DAB, ie which is the better, to a large extent the answer is not defined by a 'perfect world' technical shootout between the two, it's how they are deployed by a given station.

And finally, depending on where you live etc, you can get perfectly good DAB signals from your FM aerial, I do so. It just needs a proper splitter at the set end. After all, DAB is digital, and apart from the built in 'knee' (the sound of bubbling mud) it either works or it doesn't. If it works without mud, then the aerial is good enough, end of.

[HamishBoxer]

Good write up today about radio (DAB) in the Daily Mail. Too long to scan and post.

[Nuvistor]

Presume it is in the paper edition, looked on line and could not see it.

[vinrads]

Well nothing is forever!

Well there is something when your dead that's forever Mick

[G8HQP Dave]

Originally Posted by merlinmaxwell

One last thing, put it on band 1, only a handful of transmitters needed for country wide coverage.

Yes, a DAB+ SFN on Band 1 would give much better coverage and could beat FM on sound quality too.

[G8HQP Dave]

Originally Posted by stevehertz

And finally, depending on where you live etc, you can get perfectly good DAB signals from your FM aerial, I do so. It just needs a proper splitter at the set end. After all, DAB is digital, and apart from the built in 'knee' (the sound of bubbling mud) it either works or it doesn't. If it works without mud, then the aerial is good enough, end of.

Although it might sometimes work, an FM antenna is about the worst thing you can put up for DAB. This is because DAB is on roughly twice the frequency of FM so you get maximum impedance mismatch between the antenna feedpoint and the coax cable.

[Radio Wrangler]

Given that the feeds to the VHF/FM transmitters have been digital for a long time, I wonder how wide the channels would have to be to carry the feed data without analogue reconstruction? Lossless compression allowed.

Even if it fitted, compatibility with existing receivers would be the killer.

David

[electronicskip]

There was a full page article yesterday(Tuesday) in the Daily Mail by Radio 4s Libby Purves on the subject of FM Switch off entitled Music to my ears.
Its quite light hearted in places but deals with the fallout if it had actually happened, and covers people buying their own sets to build from kits and the BBC switch on in 1922 and the event of DAB .
Well worth a read if you haven't seen it.

[G6Tanuki]

Good to hear that FM seems to have been given a stay-of-execution: though part of me would have liked a slimming-down of the BBC's presence [at least cull the multiple local-radio-stations all broadcasting the sme stuff] in order to make my summertime band-II DX sessions easier. (It's tricky trying to hear a fading French or German station when you've got Radio Borsetshire blathering away 100KHz either side).

I tried using a DAB radio here: even taking it to the highest part of the garden I only got the main PSB MUxes which don't carry anything that appeals to me.

One downside of going DAB entirely is that it becomes a lot harder (or at least much costlier) for free-radio/experimental-radio types to put a station on-air. So likely no 21st-century DAB-equivalents of the original Radio Caroline/London/Jackie or the modern FM-band free radio stations

[stevehertz]

Originally Posted by G8HQP Dave

Although it might sometimes work, an FM antenna is about the worst thing you can put up for DAB. This is because DAB is on roughly twice the frequency of FM so you get maximum impedance mismatch between the antenna feedpoint and the coax cable.

Well yeah, we can talk about aerial theory until the cows come home. The 'real world' of aerials often tells a different story however. As we all know, it is as much a black art as it is a science. Like I say, DAB is by definition 'digital' so it either works or it doesn't (apart from the built-in bubbling mud 'knee' area). For many people the ability to use their existing FM aerial for DAB is a boon. Why erect, sometimes at considerable cost in terms of outlay, disruption and repair to decorating etc etc a separate DAB aerial when you 'already have one'? Just so that you can say to yourself that the impedance match is correct? If it works it works, and mainly it does! High up as it is (on the roof or loft), it is much better than a short T aerial hanging out of the back of the set. Plus, the FM aerial is already there, you just add a splitter at the set end. Two minute job, perfect results in most cases, theory be damned.

[terrybull]

I read yesterday that the BBC have reversed their decision to stop FM broadcasts in the future and they will continue.
It's just a shame that some of the media used the image of a biscuit tin in the form of a radio to illustrate a radio for those who weren't sure what one was.

[Andrew2]

Originally Posted by terrybull

I read yesterday that the BBC have reversed their decision to stop FM broadcasts in the future and they will continue.
It's just a shame that some of the media used the image of a biscuit tin in the form of a radio to illustrate a radio for those who weren't sure what one was.

Yes indeed. When my eyes fell on that photo in the article, I thought 'ooh, what a neat radio', but it looked just a bit too perfect and I decided it was a Photo-shop mock-up. Then I saw the rolled edges and realised it was a biscuit tin! A look on the 'net revealed lots of them!

[Dai Corner]

Originally Posted by G6Tanuki

One downside of going DAB entirely is that it becomes a lot harder (or at least much costlier) for free-radio/experimental-radio types to put a station on-air. So likely no 21st-century DAB-equivalents of the original Radio Caroline/London/Jackie or the modern FM-band free radio stations

Which is easier? Finding a suitable transmission site, getting planning permission, getting a frequency allocation from Ofcom, sourcing a transmitter and aerial and setting it all up together with a link from the studio site or renting some bandwidth from a mux operator?

The BBC are virtualising their local radio stations and if they made the facility available to community operators all they'd need would be a PC, a mic and an Internet connection.

I'd argue the technical barriers to entry could be lower than ever. Pirates would find it more difficult but that's probably a good thing.

[Hybrid tellies]

Originally Posted by vidjoman

My 1 year old car only has FM/AM radio. My son paid an extra £500 to have DAB as well. Most times the DAB does not work and the radio reverts to FM. He thinks it was a waste of money. There must be huge numbers of cars that only have FM, and even that has not got perfect coverage.

Our two cars, one is only 3 years old, only have AM/FM radios fitted. My own car is a 13 year old Vauxhall Corsa which I do not want to spend any extra money on top of the running and maintenance costs, has a good AM/FM radio fitted. So I am very relieved I do not have to think about buying and fitting a DAB radio or DAB adapter.
Around the house reception of the national FM stations is not good and is better on AM and DAB but this does make it a good test for all FM radios. Two of my best FM performers both date back to the early 1970's, Hacker Hunter RP38A and ITT/KB Tiny Super, both wiping the floor with many more modern radios.

[Junk Box Nick]

I read a document a few years ago - can't remember if it was from the BBC or who but it was a some sort of report rather than newspaper article - that one of the advantages of a switch to DAB in London was the plethora of FM pirate stations preventing many listeners from being able to receive authorised broadcasts.

I got the distinct impression that once the audience had defected to DAB, the FM band would then be abandoned by the major stations leaving it to the local independent, community and pirate stations to battle it out amongst themselves.

[G6Tanuki]

Originally Posted by Dai Corner

[Which is easier? Finding a suitable transmission site, getting planning permission, getting a frequency allocation from Ofcom, sourcing a transmitter and aerial and setting it all up together with a link from the studio site or renting some bandwidth from a mux operator?

I don't think the 1960s medium-wave free-radio types ever bothered getting planning-permission or an official frequency allocation....

Same goes for the current (FM) generation of free radio. No rented bandwidth on a DAB Mux is ever going to replace that: and while it can be done, it's much more expensive to build your own DAB transmitter.

[Andrew2]

Originally Posted by stevehertz

Well yeah, we can talk about aerial theory until the cows come home. The 'real world' of aerials often tells a different story however. As we all know, it is as much a black art as it is a science. Like I say, DAB is by definition 'digital' so it either works or it doesn't (apart from the built-in bubbling mud 'knee' area). For many people the ability to use their existing FM aerial for DAB is a boon. Why erect, sometimes at considerable cost in terms of outlay, disruption and repair to decorating etc etc a separate DAB aerial when you 'already have one'? Just so that you can say to yourself that the impedance match is correct? If it works it works, and mainly it does! High up as it is (on the roof or loft), it is much better than a short T aerial hanging out of the back of the set. Plus, the FM aerial is already there, you just add a splitter at the set end. Two minute job, perfect results in most cases, theory be damned.

I support this pragmatic approach. I have split the UHF TV antenna via a homebrew frequency diplexer. Everything above ~300 MHz goes to the telly, everything below to the DAB/FM receiver. Good results all round, all available muxes received, no bubbling mud. I know it's a mile off 'optimum' but it works just fine.

[G8HQP Dave]

Originally Posted by stevehertz

Well yeah, we can talk about aerial theory until the cows come home. The 'real world' of aerials often tells a different story however. As we all know, it is as much a black art as it is a science.

All antennas behave according to the laws of physics. Some people, including some antenna 'experts', do not know what these laws are and how they operate in certain situations. Fortunately, broadcast reception is usually easy to do because of the high signal strength so severely suboptimal antennas can still work well enough for people to draw false conclusions.