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The best DAB radio

I want to tell you which is the best DAB radio. I have it here in front of me:

Radio photo

I've seen many DAB radios in my time. My ex worked at the first BBC digital radio station when it launched, so we saw all the early models.

Old analogue radios, like a lot of analogue things, had this great built-in interface quirk. In the old days you couldn't just choose a radio station, you had to turn a dial and that would tune the frequency to the station you wanted. I'm NOT talking nostalgia here, I'm talking usability. This strange quirk meant you could learn the interface really well - the radio stations were always at the same place on the dial, and you very quickly learnt exactly how much to turn to go straight from Radio 4 to Radio 1.

DAB radio designers didn't really have this, they just had a big list of stations. In fact they had it worse than that: if there was any "natural" interface driven by the mechanics of DAB it would be a hierarchical list where first you choose your multiplex, then you choose your station. The early DAB radios forced you to do this. Firstly, navigating a hierarchical list is fecking annoying on any device that doesn't have a massive computer screen. Secondly, the hierarchical list means nothing to anyone. No-one knows intuitively if Smooth FM and the World Service are on the same multiplex or not, and they shouldn't have to know.

DAB radio designers came up with various ways round this. They added presets of course - lots of FM radios have this too. Trouble is, they generally had to add lots of buttons, especially as they needed to support both DAB and FM. Bleh. Clicky interfaces, menus to scroll through. Bleh.

Well now the perfect DAB/FM radio interface has been settled on and it looks like this:

Radio photo

It's from John Lewis (it's called the "Spectrum"), and it's a little portable thing. It does DAB, FM and USB, it runs off battery or mains, it doesn't take more than 4 seconds to turn on (unlike many other digital radios which sit around saying "hello" while secretly they're frantically booting stuff up).

But the one thing I want you to notice is how easy it is to operate it in the dark, with your eyes closed, or with one hand stirring a pot of soup. There is a very small number of buttons/knobs, and when you grab for it without looking you can instantly feel which button you're on. After a day or two you can change the station, change the volume, change DAB/FM, or turn it on/off without looking, and really that's all you need!

The minimalism continues through the interface too: there are no presets, for example. Some might find miss the lack of presets, but it takes away a lot of interface complexity. There's an implicit "two-preset" character anyway, since of course it remembers one DAB station and one FM station, the ones you had on last.

The two dials on the top are not continuous dials, by the way, they're click-wheels. I do miss a little the ability to be as subtle as you like with the volume control, but I don't mind much. On the station dial, for DAB you're wheeling through the alphabetical list, which you can sometimes do with your eyes shut but not always - but at least the stations are always in exactly the same place, it's still a learnable interface. On FM, the dial changes the frequency, as you'd expect, plus the curiously named "Reset" button does auto-scanning for you on FM, and that works fine too.

I actually bought this radio for my ex. After seeing it in action for a while, I went and bought another one, for myself!

| design |

Train seat sign usability

The sign in this video tells you whether the two seats below it are reserved or not.

What's wrong with the sign?

Well, this particular video is 14 seconds long, and during that time you can tell that the seats are not reserved for a total of about 5 seconds. At other times, if you glance up at the sign you might see nothing, just a blank screen; you might see some partial information; or even worse for about 1 or 2 seconds if you look up you'll see "reserved", i.e. the opposite of the truth!

The text of the message (the top line, at least) is "13. This seat is not reserved". If they had written it as "13. not reserved", or even better, "13. available" then the text wouldn't need to scroll, and the message would be there 100% of the time, rather than a rubbishy 36% of the time.

| design |

Trains and usability

Sometimes I think that on British trains they're performing some kind of weird experiments in bad design. The toilets on many trains have this set of buttons:

Train buttons: close, lock, open

Correct! Ten out of ten for whoever designed them, simple as they might seem. They're easy to understand and they're in the order you actually use them. But on today's train they're like this:

Train buttons: close, open, lock

Huh...? Reading down the panel, it's easy to make the mistake of only getting as far as the first button before pulling your trousers down. It seems this has happened, too, because they helpfully added a sign above the buttons which says "Don't forget to lock (L) the door!" Big hint: if you need to give users hints like that, you've designed it wrong.

One thing you could do is combine the "close" and "lock" buttons into one, since it's very rare that anyone's going to close the door from inside wanting it to stay unlocked. On a train last week they'd done that, but they'd done something else weird:

Train buttons: open, close-and-lock

Firstly the buttons are in the wrong order: since we read from left to right it gets confusing to press the rightmost button first, especially in the context of a "paragraph" where the instructions are written (for no good reason) as entire sentences. Secondly the curling pattern of the arrows sends the eyes round in a loop, making it hard to grasp in a single glance which sentence belongs with which button.

So far I've not been on a train using the scheme

Train buttons: close-and-lock, open

although it's hardly rocket science.


But, thrillseekers, that's not all. On today's train there are little LED displays to indicate whether a seat is reserved or not. They display the scrolling sentences "This seat is reserved" or "This seat is not reserved". This ridiculous interface means that, 90% of the time, you can't tell if a seat is reserved or not when you glance at the display. If they instead chose the briefer messages "Reserved" or "Available" there'd be no need for scrolling and the difference would be clear, 100% of the time.

The LED displays are high up (on the luggage racks) and not obviously associated with the seats, unlike the older system of sticking little paper tickets in the top of each seat, a technology which worked perfectly well. Literally as I write this, a young family has got on the train, looked at the seats, and concluded to one another "Oh, OK, you can sit where you like on this train", then sat in some seats which are actually reserved. The displays are entirely un-obvious, and I wonder if they're about to be the cause of a fight...


Just for completeness I should quickly mention the disabled persons' alarm button in the loos, which people apparently kept pressing because they thought it was the flush; and the buttons to open the train doors which took about 3 seconds to show any indication of reacting to being pushed (e.g. by opening the doors) - on one train I was on, the conductor kept having to announce, "If you are getting off at the next station, please push the button then wait - the doors will open eventually - don't panic and press the emergency button."

Who knows what training people go through before they put these things together, but all the mistakes are like the mistakes beginners make when putting together websites or software programs. It would be helpful to recommend to these engineers a book like The Humane Interface, or some of Jakob Nielsen's usability articles...

| design |

Turf rooves: Good, bad, or ... ?

Occasionally you see a turf roof on a building, and I always wonder whether turf rooves are a good idea or not. The Six Cities design festival in Inverness is focussed on ecological housing so this was the perfect time to find out.

I've read about and seen the traditional Icelandic turf houses. But Icelandic farmers of the past had almost no other building materials available, so it's hardly surprising they tried making houses out of turf. And besides, modern Icelandic housing has completely jettisoned turf rooves, which suggests there might be arguments against them.

Yet, various eco houses do have turf rooves - in Inverness there's the Glachbeg Croft Education Centre, for example, and the library of the Great Glen House, which according to the festival guide has "a sedum turf roof that retains heat better and is a home for insects, plants and birds." Sounds good. But if anyone is in need of heat retention it's the Icelanders, so why haven't they stuck with them?

I can think of a couple of disadvantages of turf rooves. In particular, sticking with the eco theme, we may want things like solar roof panels, or large windows set into the roof (to cut down on lighting/heating bills...), so those would "compete" with the turf for roof space... but those are recent innovations and anyway, they can presumably live side by side.

Perhaps maintenance? The big question I don't have an answer for is how much maintenance a turf roof needs. Would you really want to have to get the stepladder out and trim/weed the roof every now and again? (BTW see later for more on this)

Returning to the Icelanders, there may be a completely different reason why turf roofing is passé. Since it is cheap, simple, and has a very obvious appearance, maybe it picked up strong associations of poverty and farming. It does seem that Reykjavik's early urbanites felt it much more fitting to use corrugated steel for their rooves, with its modern appearance and bright painted colours. (It did puzzle me when I saw all the corrugated sheet metal around Reykjavik - is that really a suitable material for building warm houses, resistant to the briney sea winds?)

So for me the question is still wide open. Could turf roofing be a sensible option for a row of ordinary houses in the middle of any old town?

UPDATE 2007-05-29: Today we visited the Findhorn eco-village, where there are some turf rooves dotted around, so I asked the guide. He said that turf rooves are essentially an aesthetic choice - they are decent for insulation but have to be quite thick (for moisture retention), meaning the house needs sufficient buttressing to support the weight. So they're not particularly cheap option or with strong benefits. They also need a relatively shallow roof: less than 20% slope for grass, but sedum works better and on more slopey rooves. The guide said they typically strim their grass rooves once or twice a year, so the maintenance is not very difficult.

UPDATE 2007-06-03: wikipedia has a decent article on turf rooves.

| design |

Ecological house design tips

At various points in the Scottish design festival over the past few days I've learnt a few interesting things about building ecological houses. My main learnings:

  • I already know that big south-facing (double-glazed) windows are a very good idea, trapping heat and light from the sun (so it cuts your bills as well as saving the earth). I saw various designs which add to this by putting stone or concrete walls/floors in those south-facing rooms: these serve as heat-sinks or storage heaters and absorb heat, warming the house at night (and cooling it in the day) to cut your heating bills even further.
  • A low-tech but important measure is to protect a home from cooling winds, by putting obstacles between the wind and the house. These could be a garage, a conservatory, a bike alcove, or trees/bushes.
  • LED lighting is even more efficient than modern energy-saving bulbs, and has been improving a lot in recent years. (For example, they're very commonly used in vehicle indicator lights now.) Still, I don't find the colour of the white LED lights very "warm" - it does seem kind of stark and clinical. Could filters or other tricks help?
  • I had thought that burning wood for heating was a bad idea (all the CO2 produced), but apparently not. Wood is renewable in a way that coal and gas aren't, and although electricity is extremely convenient it is not always the most efficient way to heat things (compare gas hob cookers against electric ones, for example). It's also probably less eco-friendly, depending partly on how the electricity is produced, but also because of the inefficiencies of conversion/transmission involved in electric heating. Various "eco buildings" we visited use wood fires or more sophisticated woodchip burning systems. For domestic uses, systems that burn wood pellets are the thing to go for. You can get very compact heater/boiler systems and because the pellets are compressed they don't take too much room to store.
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