Emergency Broadcasts

Some of the frequencies listed for various areas are the ones used for local radio at the time - 1457 in London was BBC Radio London's MW frequency for example.

I suppose as they were 'peacetime services' the rest would cease

As it's a bit of a faff to read it all on Twitter, I've combined it into one PDF.

Yes, when uploading scans of a 60+ page booklet, Twitter is the last place I'd use to share them!

A couple of interesting bits:

There was (maybe still is?) the facility for the BBC to take over ITV in the event of an imminent war. I can believe that of the UHF network, but the VHF 405 system didn't have co-sited transmitters, so presumably there would need to be links between the sites to enable this to happen? Unless it would use off air transmission? Either way, however this was achieved technically, surely the fact that the engineering to do this existed would arouse suspicion as to what this seemingly redundant facility would ever be used for?

It would also seem to be a flaw in the plan to decide the Radio 4 Longwave site was unnecessary for their wartime radio service due to the regionalised FM/MW services that would be provided. Firstly, longwave radio would propagate further and be just the ticket if you're in a cellar with the rubble of your collapsed house on top of you. And secondly, surely the last thing you'd want to do is have a single point of failure that would exist by having only 1 service. Having a regionalised service is no use to you if the infrastructure gets destroyed or the regional station fails later. I would've thought it would be better to keep LW going at least until it had been verified that the entire regional network was up and running, but ideally throughout with the national information, with instructions to use the regional service if you can receive it (and providing a roundup of whatever regional information was available for the benefit of those who couldn't receive it).

Oh well, I suspect like much planning for nuclear war, this was all created more to give people something constructive to do in the last few days, rather than any genuine belief that it would work, or even if it did, that it would provide any useful information. I wouldn't need to be listening to an emergency regional service in the dark on a portable radio to know that I'm f**ked.

The IBA stuff would be trivial, BT could switch the necessary feeds, on the IBA's instruction, or an off-air pick up could be done either at the transmitters individually or at one site and fed in as if it were a regular network programme.

What isn't clear from the book is whether only the main VHF FM transmitters stated would be in use or if their relays would stay on air for a long as possible.

On a related note with regards to Long Wave, it's often stated that one of the checks with regards to the letter of last resort is to check whether Radio 4 is still broadcasting (presumably on Long Wave, unless it has other undocumented frequencies).

Back then all the circuits between the BBC and ITV, and to their transmitters were the Post Office's. Because of this I imagine putting a single service on every transmitter would be fairly straightforward and done at exchanges.

Who has a LW receiver in their home these days though? I don't even own anything that can receive MW.

They would have done back in the height of the cold war though, plenty of radios back until the 80s wouldn't have even had FM.

I still use the Radio 4 LW service fairly frequently in my car when I'm driving home through an area of poor reception and can't find an FM frequency to listen to the 6 O'Clock news on! Not everyone has DAB you know!


Putting aside that this book was written in 1975, I still stand by a point I made above - you can pick up Radio 4 on Long wave from Droitwich pretty much anywhere in the country on the cheapest of radios (assuming it has LW) without any proper aerial even when nothing else can get through. It's about the only thing you can pretty much guarantee will always be receivable. This is not true of any other form of broadcasting and there's still a lot to be said for that.

My hi-fi is capable of receiving LW, and every other radio I have including the most recent one I bought 18 months ago can receive MW signals.

DAB I'm not convinced is any better than regular FM radio quality-wise and from what I have listened to the quality of it was absolutely dreadful compared to the comparative FM transmission, and it's all because of the dropping of the bitrate to cram more stations in.

Not just the bitrate. Lots of DAB stations are now mono rather than stereo to reduce bitrate yet further (commercial stations pay for every "bit" AIUI) - presumably because most people are using mono kitchen radios...

I have quite a few FM/DAB only (some with IP as well) - but every non-DAB radio I have is FM/MW/LW and some also SW.