* Posts by Jan

6 publicly visible posts • joined 1 Mar 2009

Boffins: Ordinary lightbulbs can be made efficient, cheaply

Jan Silver badge
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LED GU10s

@ac 14:10 GMT

> Thanks for the heads up re. the GU10s - mine have only been in place for three weeks

> and all functioning happily so far.

> What brand are yours, in case others may need the same warning? I'm using the ones

> from homewatt.co.uk with the yellow surface mount LEDs, £9.99 each.

I mostly have 3W GU10s from Ryness, bought in their shops, but they also have a web site http://www.ryness.co.uk/

I'm also impressed with a 5W GU10 bought from TLC http://www.tlc-direct.co.uk/

Less impressed with the service from Initial Lights.

> I trialled a few each of the 'daylight' (white/blueish) and 'incandescent' (yellow tinge) and

> actually prefer the bluey ones, I find it a much nicer light to work under once you get used to it.

Yes, as long as you don't turn on any low colour temperature bulbs as well, then the cool white

LEDs are really good to work under, read and illuminate artworks. I like their directionality.

If you take time to set them up then one person can read in a pool of white light while the person

next to them on the sofa can view video in an essentially dark room.

Jan Silver badge

sharks with frikkin' las^H^H^^HLEDs.

@ac 11:43

>The future is LEDs - just swapped 1200W of GU10 halogens for 120W of LEDs, the cost saving

> speaks for itself even before you factor in the increased longevity of the LEDs (and the halogen

> ones pop pretty often IME)

> Going to convert the rest of the house as soon as reasonably possible!

I'm a fan of GU10 LEDs, but I'd caution you to keep your receipts. A fair proportion of built in power

supplies has a habit of failing soon after you start using the bulbs, so you may have a nice LED

light engine with 49.990 hours of ueful life in it embedded in a casing with a burnt out power supply. Once I'd exchanged the duff ones, the remainder have all continued to function. Only two and a half years use, for the oldest, so far.

@Dave

> Can anyone explain why they don't put coatings on the inside of tungsten bulbs to react

> to the IR radiation, the way that they do with fluorescent tubes?

No explanation required. Flourscent tubes produce ultraviolet light, t@he flourescent coating re-emits it as visible light.

@Tjalf Boris Prößdorf

> How is that a serious problem in most of Europe and northern America, where we need

> to heat our living quarters most of the time anyway?

Because local heat generation, whether from burning fuel or capturing solar or geothermal

energy, is usually more efficient than using distant heat generation.

Summer debut for Judge Dredd computer smart-rifle

Jan Silver badge
Alert

A lot cheaper than airborne weapons?

How long before the <insert enemy> will be able to buy or capture these?

If these guns are really smart, will they be keyed so that only US soldiers can activate them?

Aeroplane based weapons maybe expensive, but it appears that the USA's recent enemies can't afford them. These guns may level the playing field faster than SAMs.

University emails 'blocked from Hotmail'

Jan Silver badge
Paris Hilton

What a turnabout.

When I was a university postmaster I used to block Hotmail.

(Paris, for real hotmail.)

NYC granny shoots mugger with .357 Magnum

Jan Silver badge
Paris Hilton

What is it about gunmakers?

0.357 inches? Why do they choose such crazy dimensions? Why not 11/16 or 3/8 inch? How is 0.357 better than 0.356, 0.358 or 0.34? Is it the ideal fit in some, easy to specify and drill, bore size?

Paris, cos she knows what'll fit.

Lockheed offers ready-to-go supersoldier exoskeleton

Jan Silver badge
Coat

Name shifting

Ok, powered exoskeleton is a precise description, but I liked it when these things were called Waldos.

Mine's the stealth Waldo with the in-pocket fusion generator.