View Single Post
  #236   Report Post  
Posted to alt.home.repair,alt.electronics,uk.d-i-y
William Gothberg William Gothberg is offline
external usenet poster
 
Posts: 190
Default Do switch mode power supplies flicker in time with mains?

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
wrote:



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



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

wrote:



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

wrote:



"William Gothberg" "William wrote in
message
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.

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 and discuss your shortfall properly.

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.

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

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, who can all see something you can't? Is a dog a freak because it can smell better than we can? Or does it perhaps have the ability to detect what we miss?

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")."

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.

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. It makes you want to get rid of it.

I poison mice because its more convenient to
do that than to fart around with traps and never
have a problem with any smell from dead ones.


More fun to trap them and watch them slowly die.

Nevermind the advantage of smell....

Why do you think Iiyama made 90Hz monitors?

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


High frequency monitors were very popular.


Not because many ever saw any flicker.


There would be no other reason.

And it was proven that low frequency ones cause headaches and eye damage
for people using them all day in offices.


Bull****.


No it isn't. Go do some research and stop yourself being so utterly clueless. At my first place of work it was actually one of the regulations that anyone could request a higher frequency monitor if they believed it was annoying or giving them headaches.