The NICAM Codec replacement project • Hacker News Board

Re: The NICAM Codec replacement project

#61

Post by pjc50 » Wed, Jan 20, 2016, 4:23 PM UTC

logfromblammo wrote: post #53

mseebach wrote: post #27

Earlier quoted context omitted.

They most likely aren't ATA cables, as in, they aren't used to connect hard drives -- so it's not obvious that whatever purpose they serve could be served by a serial alternative. If you look at the photo of the back of the unit, you see a lot of very wide D-Sub sockets that these ribbon cables seem to connect to, so the unit is meant to connect to a bunch of other things. Actually, the need for these sockets seem to…

If you're designing your own boards with ribbon cables connecting them, I imagine that you could save a lot of money on parts by using 40-pin connectors with PATA cables--we're talking entire cents, for each of the 2 units. Also, I'm willing to bet a place like the BBC has boxes filled with spare PATA cables and 16MB SIMMs and 8 GB internal hard drives, and maybe even a room with a bunch of dusty 17" CRT monitors in…

Exactly. And it has to connect to the same system as the original 1980s units, so whatever protocol it's using will be old. DB25-serial? SCSI? IEE-488? It would have been nice to have a few technical details on the system.

Random BBC-related anecdote: the Cambridge University computer lab had, up to 1999, an info TV in the lobby driven by a 20 year old BBC micro in Teletext mode. This was apparently because it had an extremely powerful video output (more so than modern hardware) and the display was at the other end of 50m coaxial cable.

Re: The NICAM Codec replacement project

#62

Post by daveguy » Wed, Jan 20, 2016, 4:44 PM UTC

I appreciate a good success story about major transitions / upgrades / process changes / etc. Those situations where there is usually SOME glitch and you have to engineer the hell out of it to get a perfect transition. The only reference to testing was "We had the Codec tested for both safety and EMC." Was that in house or external? Surely there was some major transition testing low power broadcast tests, etc to make sure everything went smoothly. Or did they just get really lucky? Seems like there's more story to this.

Re: The NICAM Codec replacement project

#63

Post by gpvos » Wed, Jan 20, 2016, 4:47 PM UTC

TeMPOraL wrote: post #19

Piskvorrr wrote: post #10

Earlier quoted context omitted.

Well, I'd assume that the reason for radio silence (ahem) on broadcasting tech would be various NDAs.

It has been claimed that a literal radio silence of BBC could cause a nuclear strike. https://en.wikipedia.org/wiki/BBC_Radio_4 (C-f nuclear)

The operative words there are "it has been claimed that".

This may have been true in the past (although really no official confirmation has ever been given), but it most probably is not true anymore, as the valves of the 198 kHz transmitter at Droitwich are of a design that is not available anymore and there is a limited supply left; when that is depleted, the transmitter will shut down.

Although there are claims otherwise, see the note at the bottom of https://en.wikipedia.org/wiki/Radio_teleswitch#Transmitter_O...

Re: The NICAM Codec replacement project

#64

Post by sandGorgon » Wed, Jan 20, 2016, 4:50 PM UTC

jhallenworld wrote: post #35

I can see from the photos that it's using this board: http://zedboard.org/product/zedboard I'm surprised BBC is not only willing to make custom hardware, but custom RTL design as well. I'm curious what the failure rate of the FPGA will be, I mean they are more susceptible to soft errors than CPUs or ASICs. Maybe BBC will fund making a custom ASIC :-) Well I see two systems, maybe they are redundant that way. Why not…

+1 for the open source part. I would really love to see the RTL for the FPGA.

I wonder if they're using the Zedboard or the actual 7000 soc.

Re: The NICAM Codec replacement project

#65

Post by nekopa » Wed, Jan 20, 2016, 4:52 PM UTC

kokey wrote: post #42

linker3000 wrote: post #6

That's some decent BBC engineering from a team that works away quietly in the background and just makes things happen, or keep happening. I don't work in that field, but like many people in my profession (Systems and networking), I also tend to be invisible until something breaks, and then I am the fall guy if it's not fixed within a heartbeat. /I was half expecting the article to outline how a box full of 80s techno…

I would hope so with a £5.1 billion budget. That's more than half the FTSE 100 companies.

The engineering team has a budget that big? Do you know what the budgets are for the other aspects of the BBC? Like TV and radio broadcasting, production of TV and radio shows, administration, HR and other areas?

Edit: found an old breakdown here:

https://en.m.wikipedia.org/wiki/BBC#Expenditure

Seems like their whole technology department has a budget of £175m

Re: The NICAM Codec replacement project

#66

Post by gpvos » Wed, Jan 20, 2016, 4:53 PM UTC

ajdlinux wrote: post #16

jacquesm wrote: post #4

Very nice work. What is the rationale behind doing a bespoke design rather than sharing the development cost with all the European broadcasters, is NICAM unique to the UK? What do other broadcasters use for similar services?

https://en.wikipedia.org/wiki/NICAM seems to indicate that while NICAM is used by a few broadcasters here and there, it was initially developed by the BBC, and it's no longer as widespread in Europe as it once was.

See makomk's comment nearby: NICAM's use for stereo sound with analogue TV broadcasts is not the same as the use for the BBC's internal audio distribution system.

Re: The NICAM Codec replacement project

#67

Post by gpvos » Wed, Jan 20, 2016, 5:00 PM UTC

What I missed in the article is whether there was an audible glitch at 4:15 AM.

Re: The NICAM Codec replacement project

#68

Post by SilasX » Wed, Jan 20, 2016, 5:10 PM UTC

acheron wrote: post #17

Really interesting article, but terrible clickbaity title. I wouldn't have read it if there weren't so many positive comments on HN already. It could work if there were a subtitle. "35 million people didn’t notice a thing: BBC Radio's NICAM Codec replacement project". I dunno. But it is (or should be) very important that the title actually informs you as to what the article is about. "35M people didn't notice a thing…

Yeah, the HN title should be more like "Changing the NICAM radio transmission protocol without 35 million people noticing."

Re: The NICAM Codec replacement project

#69

Post by a_humean » Wed, Jan 20, 2016, 5:14 PM UTC

thorin wrote: post #59

jmtd wrote: post #29

Earlier quoted context omitted.

Perhaps the title-writer has been infected by the BBC news editorial policy. They seem to be turning clickbait titles into a fine art, combined with renaming articles so you think it's a new piece on the same story, but turns out you've already read it. (If you read BBC News at all that is: my wife still does, I gave it up years ago and haven't looked back.) I love many aspects of the BBC but sadly not their news out…

I used to think the BBC news was definitive 5-10 years ago. I'm not sure what has changed? Have the recent governments and their pressure on the license fee really made the difference or is it just my perception? When I was young the BBC was always seen as pretty left wing (it certainly wasn't at it's inception though) it seems pretty conservative (and sensationalist) right now.

The Iraq war and David Kelly's suicide is what happened:

https://en.wikipedia.org/wiki/Hutton_Inquiry

Add things like the Jimmy Savile abuse scandal, and the ongoing threat from the conservative government to turn the BBC into the equivalent of America's PBS (irrelevant on the political landscape, lacking financial heft, and in close to nonexistent viewership) and you have a recipe for a neutered public news broadcaster too afraid to do anything meaningful.

Re: The NICAM Codec replacement project

#70

Post by kokey » Wed, Jan 20, 2016, 5:15 PM UTC

nekopa wrote: post #65

kokey wrote: post #42

Earlier quoted context omitted.

I would hope so with a £5.1 billion budget. That's more than half the FTSE 100 companies.

The engineering team has a budget that big? Do you know what the budgets are for the other aspects of the BBC? Like TV and radio broadcasting, production of TV and radio shows, administration, HR and other areas? Edit: found an old breakdown here: https://en.m.wikipedia.org/wiki/BBC#Expenditure Seems like their whole technology department has a budget of £175m

Europe average R&D spend cross industry is just above 4%, but that's mostly pulled up by R&D on healthcare (which is closer to 18%). Without healthcare I think it's around 2%. I would hope to see them spend at least £100m on R&D, but that's obviously not just on broadcast technology.