No more filament bulbs

[Clive Mitchell]

In message , Frank Erskine writes

With pulse width modulation you can accurately dim an LED from full output to 0.01% with digital accuracy.

[<me9]

I have two dusk to dawn ones, 2D 16w

Nowt so dim as me.

What are they? I'm obviosly not concerned.

(100% CFL (bar one flou) for at least 10 years)

[<me9]

Leds

they seem to be available for the broadcast industry. (possibly cameras are more sensitive now).

Easily, switch some off. If low voltage (current limited) fed, reduce the current.

[Mike Barnes]

OK, but can you tell that by looking at them while walking past on the street?

[The Natural Philosopher]

But they strobe abominably.

Maybe a capacitor would help..

[Mike Barnes]

Well, if it's offending your taste in living-room light fittings or global catastrophe, it's obvious what's more important, innit? :-)

Seriously, though, it needn't be that bad. A few years ago, when CFLs were a lot clunkier than they are today, I went round this (quite large) house replacing every standard-fitting (BC or ES) bulb with a CFL. There were about 50 bulbs in all. Out of that lot, four fittings (one of one type and three of another, all wall lights) had to be replaced. Although I found it objectionable at the time, I replaced the four fittings (quite cheaply, as it turned out) because I Knew It Made Sense, and I've never regretted it.

My guess is that a future phasing-out of incandescent lamps will start with standard BS/ES fittings, where the vast bulk of the savings are to be made, and the more esoteric types will follow quite some time later.

[Huge]

At 3dB loss per exchange, the ensuing call wasn't much fun.

Much easier to use the UAX13 "STD access" bug.

(Dear Mr. BT Investigation Department; this was all 30+ years ago. These days I pay my phone bill, OK?)

[Andy Hall]

Yes, it is, because the suggestion that "global catastrophe:" or anything approaching it can be remotely influenced by whether or not crappy CFL bulbs are used in domestic property is patent nonsense.

This is imply a ruse to "give the plebs something to do" which will have the effect of making the gullible feel good while diverting the issue away from the major contributions of CO2 - always assuming that it is accepted that climate change is as a result of CO2 emission and that man has some ability to influence it.

It is that bad. The light quality of these things remains apalling.

If at all. I am sure that ways will be found around this nonsense, if it ever happens.

This is the first time that I can think of where the development of a new lighting technology is coupled with attempts to explicitly remove others from the market by legislation.

We can still buy candles, oil for oil lamps and the mantles etc. for gas lamps. The free market has moved in the direction of electric lighting by choice.

Likewise, the free market should be allowed to decide this issue as well. The two basic arguments being made by the CFL lobby are that money is saved and that there is an improvement in CO2 emissions. Buying patterns and shelf space indicate otherwise and it is then said that people are taking a short term, purchase outlay view as opposed to the life cost. This may be true to some extent.

However, the moment that there is a suggestion of legislation to remove a product from the market as opposed to allowing people to make their own decisions indicates that the arguments were weak in the first place, which they are.

[Andy Hall]

Absolutely. I can see any of them quite distinctly from the light quality, whether it's walking past them in the street, walking into a hotel room, or anywhere else.

The one application that I would consider for CFLs is outside, overnight security lighting, because basically I don't have to look at the light from the things.

[Andy Hall]

I wonder what would have happened if one were to dial the codes back and forth or in a circle back to the starting exchange.

[Tony Williams]

When I worked at Ferranti in Bracknell, (before STD), one of the lunchtime competitions was to do exactly that. You needed two phones near to each other, both with direct dial out. Then tap from local exchange to local exchange and finally back to the nearby phone. The winner of course was the one who went through the highest number of exchanges.

Reminiscent of "All Gas and Gaiters" and their railway competition. The quickest place to place using Bradshaw's Timetables book.

Jeez. That's showing my age.

[Brian Sharrock]

Omigod! Was this 'game' introduced to Bracknell by an expatriate Scouse who'd worked at ATE ? We played it too ... then came Crossbar.

[Huge]

I've done this between adjacent telephone boxes.

[Clive Mitchell]

In message , The Natural Philosopher writes

Not if the PWM is done at a high enough frequency. In some cheap disco lights the PWM was done at something like 50Hz which they then tried to hide by softening the edge with a capacitor on the input of the drive transistor. Their low frequency was down to trying to achieve too much from a common processor.

My own control system for RGB colour changing uses a PWM frequency of about 350Hz to avoid flicker.

[Tony Williams]

I don't know where it came from. Such things would be all the rage for a few months, then off onto something else.

[The Natural Philosopher]

Sill get strobing effects. Most disturbing.

[Clive Mitchell]

In message , The Natural Philosopher writes

Only if swished back and forth vigorously to make the effect visible. Still less than a traditional fluorescent tube or discharge lamp by a large margin.

[Mark Carver]

Yep, I'll make space alongside my stockpile of red and black T&E.

[Mike Barnes]

No, what I meant was how could *John* (whose words have been snipped) tell that they *couldn't* take CFLs?

[Andy Hall]

Ah, I see what you're saying.