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Techno-Follies

Select samples of silliness in the modern world

Consider this page a place to vent. Rant factor may be higher than usual.

Blue LED Blues

These days, almost any electronic device that wants to be modern, flashy and/or gimmicky just has to use blue LEDs somewhere - be it as status indicator, LC display backlight or more or less just for fun. Those implementing them do not always seem to be aware of the implications.

  1. As with a lot of things fashion related, it wears off. The effect may be nice at first, but in the long run it's just lame. Blue LEDs have become common and inexpensive, so in the meantime everyone and their dog use them.
  2. Fashion aside, the blue LED light poses some significant ergonomic issues. It cannot be focused correctly be the human eye, which most obviously shows itself as halos around such light sources in only moderately dark surroundings (to make matters worse, the LEDs usually are plenty bright, too). Blue backlights are equally affected and thus counterproductive when optimum readability is to be ensured (which should be the goal for just about any display).
  3. Bright blue LEDs tend to be placed where they are most disturbing to the user – more thoughtlessly than intentionally, I guess.

As you can see, just because something is flashy and new doesn't mean that it should become standard without further thought.

Some tips for implementation:

  1. Think about what you're doing. This is the first and most important step.
  2. If you do want to use blue LEDs, be conservative with the current. Take a look at a prototype of the product under average to low lighting to ensure the light is not disturbing. I don't want to know how many of the little buggers have ended up being taped over – at least three in this household.
  3. If high efficiency lighting is desired that is easy on the eyes, use amber / orange LEDs. (Green ones are a little behind in terms of radiation, and even the higher eye sensitivity there cannot compensate this. Yellow ones with good efficiency should be available, but personally I don't consider the color to be all too cozy.)
  4. For nighttime use, e.g. clock numerals, I'm a fan of classic red. Perhaps this points to red lighting having been used in subs for good reason?
  5. If you do feel like getting gimmicky, try implementing something useful. Ambient light based brightness controls, for example, are to be seen far too rarely on devices that could use them (and they're nothing new – Grundig used LDR based circuits in clock radios 30 years ago).

Don't give users the blues. Leave halos to saints.

Glossy LCD Panels

This is a classic example of regression being sold as progress. Noone in their right mind would have dared selling a display without even the slightest bit of anti-reflective measures 10, 20 or 30 years ago. These days, you may walk into an electronics store and find that every single notebook computer sold there has a glossy, "glare-type" LCD panel, with only a few expensive samples having some anti-reflective coating (like the Sonys that pioneered this kind of surface).

The classic matte surface is not the be-all and end-all, of course. In the days of CRTs, it was an inexpensive option for greatly reducing reflections on curved surfaces, which are not easily coated precisely at all. It is quite effective, but trades off some contrast by allowing ambient light to be diffusely reflected.

This is why glossy screens can give very good contrast and usually look good during movie playback. The advantage becomes very questionable, however, when the display makes a good mirror and not only shows the user's face, but also any brighter light source in the background during common "office-type" tasks. Accordingly, notebooks with glossy screens tend to be unsuited for outdoor usage, where their matte-screen counterparts remain at least somewhat usable.

Given this, I am absolutely at a loss of an explanation for why glossy panels are so dominant among mobile computer screens these days – if proper anti-reflective coating is too expensive, matte certainly is the better option by far. Now I wouldn't care if at least one had the choice, but alas, you really have to look hard to find matte screens in notebooks targeted at Joe Average. (My dad's new one has a matte screen – it still has a glossy black palm rest that'll attract dirt, but at least offers comprehensive connectivity in return.)

Enigmatic Icons

Sometimes I'm under the impression that the newer the software, the less good the application icons. Today they are more flashy, 3D-ish, colorful and pretty than ever, but frequently also less useful than ever! Why? Well, if we're talking Windows, try identifying an application quickly when switching tasks or in the taskbar. Icons that exhibit low contrast and don't even show a characteristic shape against the usual grey background will lose out pretty badly under these conditions. And among today's hi-color icons, these aren't too uncommon!

Examples (obtained with ResourceHacker):

I know: Designing good icons is not at all easy. You typically need to take care of:

That means just as many versions. All of these have to maintain a characteristic shape and good contrast. Quite a bit of work, and consumed time of course. Good icons, when done commercially, are not cheap! If you need a whole bunch, it could become slightly expensive. In the case of Microsoft, this is likely to be part of the problem – besides, I'd guess that marketing types would take a prettier, but not very functional icon set over one that is not as flashy, but does far better in all-day life any day of the week. Things that are pretty but impractical always sell, while those with continued value may need a little more explanation – and long-term thinking currently is out of fashion anyway.

Mysterious Menu Operation on Monitors

Well, the menus themselves tend to be more or less self-explanatory, but navigation with the associated buttons (even when those are easy to find and identify and have a reasonable size, which is not always the case) can be frustrating. For example, I always have trouble with those vertically arranged menus that you find on many less expensive models, apparently BenQ OEM'd. (My Samsung 191T's menu by comparison is a joy to navigate.)

Stupid Rubber Buttons on Measurement Gear

With measurement gear having a price tag comfortably in the 5-digit range, you can usually rely on it being built like the proverbial tank – solid metal chassis, die-cast front, pretty much like it was 20 years ago. Well, almost. There is just one little thing that drives me up the wall: Instead of having good old mechanical key switches for buttons, the current crop of devices typically uses primitive chiclet keys. It is probably cheaper, allows more flexibility in terms of button sizing and shape and reduces height internally, but the result is very mushy-feeling and imprecise – in other words, from a user perspective it's junk. (A button press might not register, or even register twice, which on some devices can make the software hiccup.) It feels very cheap, too. Now would anyone consider equipping a car (which costs about the same) with a flimsy little plastic steering wheel from a children's toy car? I don't think so.

Interestingly enough, a large number of such devices are manufactured right here in ol' Germany (both Agilent and R&S), and there certainly is no shortage of switch manufacturers here, quite the contrary.

Therefore, if you are in charge of developing a front panel for such a device, please consider using mechanical keyswitches, at least for the softkeys. (On the R&S FSUP that I used, for example, there was no obvious way of performing their functions when using an external keyboard.)

Bus User Gripes

Since I am dependent on public transport, I see quite a few different buses, predominantly Mercedes-Benz' or Setras of highly varying vintage. (Interestingly, my favs are models that seem to be about 25 years old.) The newer ones in particular have a few user interface issues as well:

O headphone output, thou unspecified one

Manufacturers of hi-fi components have this really annoying habit of equipping their products with headphone outputs without bothering to specify their performance in any sensible way. You might get "suitable for headphones from 32 to 600 ohms" or "suchandsuch mW, 32 ohms" – or nothing at all. Now this may have sufficed back in the day, but in this day and age where headphones constitute serious hi-fi gear, it is unacceptable.

As a user of a headphone output on a hi-fi component, I am interested in whether it will be suited for the model of headphone I'm using. That implies (a) sufficient output power for normal volumes and (b) a frequency response worthy of the "hi-fi" label. The latter is almost universally overlooked.

Headphones are an Ohmic load about as much as loudspeakers – i.e. not very much. They may exhibit significant variation of impedance over frequency, up to almost a factor of 5 (e.g. Sennheiser HD555/595: min |Z| = 50 ohm, max |Z| ~= 230 ohm in the audible range). If a certain amount of amplifier output resistance comes into play, you'll get a complex voltage divider. In effect, the frequency response will be distorted. Fullsize headphones usually have an impedance peak in the midbass range, so they can potentially get very bass-heavy and boomy. Single-driver IEMs would get very midrange-y under the same conditions, and Multi-driver IEMs can be all over the place.

Now there are some models that are very sensitive to this due to low and highly varying impedance, and others that aren't as critical by far – you can look at this using raw data from Headroom and a little spreadsheet. Many are optimized for low output impedances, but some prefer something in the 100..150 ohm range. Whatever the case, it is important to know the output impedance. Yet does anyone ever bother to specify it? Nope, or at least very, very rarely.

So much for one big hurdle. Another point of interest would be the noise level in µV, A-weighted. With the headphones' sensitivity spec and output impedance, it is easy to calculate the background noise level observed by the user (a spreadsheet may help). A S/N spec is less user-friendly as it involves a larger number of variables and conditions, but may be necessary if e.g. noise level varies a lot with volume setting.

Interfering Electronics

These days, many a household is stuffed with all kinds of mains-operated electronic devices and gadgets. However, not too infrequently they come at a greater price than what they cost in the store – they may generate significant electromagnetic interference. This tends to be especially noticeable in the longwave, mediumwave and shortwave frequency ranges with their bandwidth-efficient but more susceptible AM and AM-derived modulation schemes, marring reception there. It's bad enough when your own devices do it, but some of these interference generators can be plainly audible dozens or even hundreds of meters away! You can imagine what that means in any kind of remotely urban area – forget about any kind of weaker signal on shortwave while the neighbors are watching TV.

Of course, there are some EU-wide guidelines for electromagnetic compliance. Devices bearing the mandatory CE marking must comply with electromagnetic radiation limits. However,

  1. Those radiation limits aren't particularly strict to begin with, and
  2. there is quite a number of devices around that doesn't even comply with these, since
  3. most people are not even remotely aware of the problem and thus will choose their devices based on everything but EMC considerations. (Try telling people that their fancy new TV is interfering with your radio reception!) Since EMI suppression does cost a bit of money, this makes a good opportunity for manufacturers to cut corners. They can do this since
  4. The CE marking does not imply that a device has really undergone independent EMI testing (a somewhat costly procedure which any self-respecting manufacturer will carry out nonetheless), but rather that the manufacturer or importer assures compliance with the respective regulations. If a device is found not to comply, it can become rather costly for them. Thus if in doubt, they usually prefer solving interference issues on a by-case basis (which also allows covering those cases with unacceptable interference in spite of device compliance).

This situation is not what I'd call acceptable. For any one heavily interfering device that is exchanged or fixed, there will be a number of others that if in doubt will be contributing to a general noise floor, especially in urban areas. My location is quite suburban, yet I have high noise levels in the evening coming from the plasma TV in the living room, the neighbors' TV (or so it seems, sounds like SMPS interference), and wherever else; there are a few more plasmas audible around, too, and I've heard something that could be PLC noise, too. If you can afford to be a nightowl, it's less of a problem, but as part of the working population you're pretty much screwed.

It's not like I'd want the super-strict regulations of the olden days back (which were the reason that some shortwave sets were sold without external antenna jacks due to possible excessive LO radiation), but the situation as-is isn't exactly ideal either. It should be a matter of standards that the RF spectrum is kept clean, just like you wouldn't leave your garbage by the wayside.

The part that really makes me angry is that the burden of getting the frequencies clean is placed upon those who want to use them, typically amateur radio operators or SWLs. YOU have to tell your neighbors that their fancy plasma TV or whatever is interfering with your radio reception (they may not give a damn), YOU have to call on authorities to make measurements (at least those tend to be more responsive here than, say, in the UK), and it can take many weeks before such a problem is finally resolved. YOU pay the price for the manufacturer saving a few pennies.

Possible bad (and I mean BAD) interference sources include:

It is not too hard to find out whether a certain device radiates too much – if its emissions are plainly audible on a reasonably-sensitive LW/MW/SW/FM portable (100€ price class will do easily) when you're more than, say, 1.5 m or 2 m away, then chances are it does.

Contact me

Created: 2008-03-16
Last modified: 2010-11-19