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William Gothberg William Gothberg is offline
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Default Do switch mode power supplies flicker in time with mains?

On Sun, 23 Dec 2018 22:28:10 -0000, Rod Speed wrote:



"William Gothberg" "William wrote in message
news
On Sun, 23 Dec 2018 17:38:42 -0000, Rod Speed
wrote:



"William Gothberg" "William wrote in message
news On Sat, 22 Dec 2018 23:33:40 -0000, Rod Speed
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"William Gothberg" "William wrote in message
news On Sat, 22 Dec 2018 23:01:40 -0000, Rod Speed

wrote:



"William Gothberg" "William wrote in
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news On Sat, 22 Dec 2018 21:18:35 -0000, Rod Speed

wrote:



"William Gothberg" "William wrote in
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news On Sat, 22 Dec 2018 02:55:55 -0000, Rod Speed

wrote:



"William Gothberg" "William wrote in
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news why does google have 4.5 million results for the car light
flicker?

Just a few mindlessly ranting freaks, like you.

I must have asked about 30 people I know about it, and about half
agreed
it was irritating.

The technical term for that is 'pathetically inadequate sample'

I've done statistics at uni,

And clearly the whole lot went right over your head, as always.

I know what an adequate sample is.

You clearly don't with that steaming turd above.

Well I understand this,

No you do not.

How can you possibly know if I don't?

From that stupid claim of yours above.


It's your end that's stupid.


Everyone can see for themselves who the stupid is, you.

do you?

Corse I do.

Don't believe you.

You have always been, and always will be, completely and utterly
irrelevant. What you may or may not claim to believe in spades.


Stop backpedalling


Just another of your pathetic little drug crazed drunken psychotic fantasys.

and discuss your shortfall properly.


There is no shortfall of mine.


You always give up and quote the same "insults" when you don't have an answer. I have you backed into a corner because you haven't a ****ing clue what you're talking about. You're so predictable.

https://en.wikipedia.org/wiki/Sample...pothesis_tests

To make it easier for you:
https://www.qualtrics.com/blog/calculating-sample-size/

For example, with the world population of 7.5 billion, to be 90% sure
you
only have an error margin of 10%, you only need 63 people in your
sample.

So yours is clearly a pathetically inadequate sample.

It's half of what's required for the above accuracy. I don't need that
much accuracy. Even if I was 20% out, then saying that 50% of people
can
see flicker means that 40% can. 40% is a big enough part of the
population to cater for.

Thanks for that completely superfluous
proof that you don't in fact have a ****ing
clue about even the most basic statistics.


If you did, you'd tell me what I did wrong.


Already did.


No, you gave no information, you just said "bull****" etc.

If half could actually see car lights flicker, the
designers wouldn't have designed them like that.

Economy.

Doesn't cost anymore to say double the pulse
rate so that even freaks like you can't see it.

I assume the higher switching speed needs better transistors etc.

You're wrong with the rates involved.


Funny how they don't all do it.


Because the designers can't see it and didnt bother to research
what flicker fusion thresholds are out there with you freaks.


A designer who only designs something to be suitable for himself is an idiot.

Funny how it's only recently we've had them fast enough to make switch
mode power supplies and smaller coils possible.


Those operate at much higher rates again.


There must be a reason they don't just make them switch very fast, perhaps it wears the LED out?

In spades with movies in movie theaters. That frame
rate was chosen because most couldn't see that flicker.

Not the same thing.

Corse its still flicker for freaks.

It's less visible.

Still visible for freaks.


Why do you persist in calling half the population freaks,


It isnt anything even remotely like half the population.


Yes it is, by simple observation of those around you. Don't you ever talk to anyone?

who can all see something you can't?


Because thats what they are, freaks.

Is a dog a freak because it can smell better than we can?


No, because its only the freaks of dogs that can't.


Ah, so you just accept the majority as being correct. So Einstein was a freak because he was one of very few people who was that clever. You would have had him burned at the stake wouldn't you? I mean it's not normal to be that clever, there must be something wrong with him, best we get rid of him?

Or does it perhaps have the ability to detect what we miss?


Yes they do with sound unless they have gone deaf.
My parents believed that dogs had ESP because they
can work out when one of them is coming home long
before any human can. The answer is trivial, the dog
can hear the family vehicle long before a human can.


Which makes them useful, they can do something we can't. A human who could do the same would be equally useful, yet you'd call them a freak.

LED lights on cars are deliberately pulsed to get more effective
brightness (as far as the human eye is concerned, peak brightness is
what enables you to see better) from the same LEDs with less heat..
But LEDs go completely off between pulses.

And so doubling the pulse rate doesn't cost anymore.

Movie theatres (you mean cinemas,

No I do not.

theatres are for plays, they have a stage,

Movie theaters arent for plays and they don't have stages.

you're talking American)

Wrong, as always.

Cinema = big screen and projector.
Theatre = stage with live actors.

Wrong, as always.


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

"Theatre or theater[1] is a collaborative form of fine art that uses live
performers, typically actors or actresses, to present the experience of a
real or imagined event before a live audience in a specific place, often a
stage. The performers may communicate this experience to the audience
through combinations of gesture, speech, song, music, and dance. Elements
of art, such as painted scenery and stagecraft such as lighting are used
to enhance the physicality, presence and immediacy of the experience.[2]
The specific place of the performance is also named by the word "theatre"
as derived from the Ancient Greek θ*ατρον (théatron, "a place for
viewing"), itself from θεάομαι (theáomai, "to see", "to watch", "to
observe")."


Thats just one type of theater, stupid. Even you
must be aware of operating theaters which have
no stage and no play being performed.


They also have live people in them. A cinema just plays a film, no people are present.

Pity about
https://en.wikipedia.org/wiki/Theatre_(disambiguation)


https://en.wikipedia.org/wiki/Movie_theater , linked from your own link.
"A movie theater (American English),[1] cinema (British English)[2] or cinema hall (Indian English)[3] is a building that contains an auditorium for viewing films (also called movies) for entertainment."
Only Americans get it wrong. The language is English, not American.
Australia is a British colony, not an American one, you even use our Queen ffs.

don't illuminate the screen with LEDs.

Duh. And irrelevant to whether the frame rate was
chosen because most don't see any flicker with it.
Flicker didn't only happen with LEDs, stupid.

They happen more so as they switch on and off instantly.

Wrong, as always.


LEDs switch on ad off faster than any other form of light, that is an
indisputable fact.


Irrelevant to the fact that it isnt how quickly
they switch that matters, its the pulse RATE
that determines how visible the flicker is.


Bull****. Consider a variable duty cycle. As that approaches 1, there's no flicker. Clearly LEDs have a much lower duty cycle than that. A decent phosphor coating on a CRT will have a duty cycle of say 0.8 to 0.9, which will be much harder to see flickering.

Why do you think Panasonic made a 100Hz TV?

Because some freaks can see flicker at 50Hz and are free to pay more
for
something faster.

Being able to detect something you can't makes them better than you..

Even sillier than you usually manage and that's saying
something. Much worse in fact when car lights flicker.

Perhaps you should ditch your sense of smell, because smelling things
you
don't like is annoying.

There is nothing that I find annoying about any
smell except a big rotting animal corpse in hot
weather and that's so rare that it just isnt a problem.


Being able to detect (and being annoyed about) something that smells bad
is a good thing.


Wrong, as always, particularly with stuff like paint etc.


Paint doesn't smell bad. Bad smells mean something is harmful, like ****.