geekhack

geekhack Community => Other Geeky Stuff => Topic started by: Phaedrus2129 on Sat, 12 March 2011, 00:54:40

Title: Subjects more confusing than Alps switches
Post by: Phaedrus2129 on Sat, 12 March 2011, 00:54:40
Such as power supplies:

Quote
Cynism aside, their going for active-clamp reset forward then doing synchronous buck from 12 to 3.3 and 5 V is pretty ballsy. If they did it right, this could be pretty good, actually. With properly set switch delays (and frequency) they can get nearly lossless turn-off of the main switcher(s). Also, during steady-state operation, the clamp capacitor's voltage will be equal to the ratio of input voltage over (1 - duty cycle). And since the duty cycle decreases as the in-voltage increases, the voltage on the clamp capacitor will adapt to maintain the equality. This enables the use of a low drain-source breakdown voltage MOSFET in the reset section, which means lower RDS |on| and lower gate charge, meaning less power is wasted. Add to that the leakage inductance is returned to source, and you have high efficiency with inexpensive silicon.
http://www.jonnyguru.com/forums/showpost.php?p=74386&postcount=22


(http://1.bp.blogspot.com/_zE8CzamN1Y0/SniCWCU2hUI/AAAAAAAAAdc/K8LcusCKhss/s320/gil-head-explode-again.gif)
Title: Subjects more confusing than Alps switches
Post by: killy on Sat, 12 March 2011, 01:31:27
Most of it is jargon.
Title: Subjects more confusing than Alps switches
Post by: Phaedrus2129 on Sat, 12 March 2011, 01:43:01
Quote from: killy;310299
Most of it is jargon.


Even if you know the jargon it's hard to get your head around.
Title: Subjects more confusing than Alps switches
Post by: woody on Sat, 12 March 2011, 04:02:50
Just try math entry on Wikipedia.
Title: Subjects more confusing than Alps switches
Post by: muchadoaboutnothing on Sat, 12 March 2011, 10:17:12
Quote from: woody;310328
Just try math entry on Wikipedia.


Mediawiki uses AMS-LaTeX, that's not difficult at all.
Title: Subjects more confusing than Alps switches
Post by: Phaedrus2129 on Sat, 12 March 2011, 10:49:40
How is a power supply a peripheral? It's inside the computer.
Derp.
Title: Subjects more confusing than Alps switches
Post by: Moneyless on Sun, 13 March 2011, 14:25:26
Quote from: Wikipedia
Nimtz told New Scientist magazine: "For the time being, this is the only violation of special relativity that I know of." However, other physicists say that this phenomenon does not allow information to be transmitted faster than light. Aephraim Steinberg, a quantum optics expert at the University of Toronto, Canada, uses the analogy of a train traveling from Chicago to New York, but dropping off train cars at each station along the way, so that the center of the ever shrinking main train moves forward at each stop; in this way, the speed of the center of the train exceeds the speed of any of the individual cars.[42] Herbert Winful argues that the train analogy is a variant of the "reshaping argument" for superluminal tunneling velocities, but he goes on to say that this argument is not actually supported by experiment or simulations, which actually show that the transmitted pulse has the same length and shape as the incident pulse.[40] Instead, Winful argues that the group delay in tunneling is not actually the transit time for the pulse (whose spatial length must be greater than the barrier length in order for its spectrum to be narrow enough to allow tunneling), but is instead the lifetime of the energy stored in a standing wave which forms inside the barrier. Since the stored energy in the barrier is less than the energy stored in a barrier-free region of the same length due to destructive interference, the group delay for the energy to escape the barrier region is shorter than it would be in free space, which according to Winful is the explanation for apparently superluminal tunneling.[43][44] A number of authors have published papers disputing Nimtz's claim that Einstein causality is violated by his experiments, and there are many other papers in the literature discussing why quantum tunneling is not thought to violate causality.[45]

http://en.wikipedia.org/wiki/Faster-than-light#Faster_light_.28Casimir_vacuum_and_quantum_tunnelling.29


(http://i177.photobucket.com/albums/w204/moneyless27/1292275600196.jpg)
Title: Subjects more confusing than Alps switches
Post by: keyboardlover on Sun, 13 March 2011, 14:29:03
Quote from: ripster;310430
I'm  only interested in confusing subjects I can tap:  Keyboards and Women.


Psssh. And you claim I drive the ladies away!
Title: Subjects more confusing than Alps switches
Post by: mr_a500 on Sun, 13 March 2011, 16:04:12
Quote from: ripster;310430
I'm  only interested in confusing subjects I can tap:  Keyboards and Women.

Show Image
(http://modmyi.com/forums/attachments/iphone-2g-3g-3gs-ipod-touch-1g-2g-3g-new-skins-themes-launches/50281d1211568945-new-babe-keyboard-released-keyboard1.png)


I know what I'd be typing.. "B..B..BB..X..B..X.." (...just hope the keyboard has "n-key-****over")

Actually, I think in this case, "multi-touch" would be much better than a keyboard.
Title: Subjects more confusing than Alps switches
Post by: Hak Foo on Sun, 13 March 2011, 22:32:57
Power supplies are boring until the day your machine starts behaving less like a PC and more like a particularly tight slot machine because your power supply was poorly made.
Title: Subjects more confusing than Alps switches
Post by: Hak Foo on Mon, 14 March 2011, 00:16:28
I have this big-ass Delta 600W unit; weighs like 6kg, and had an Intel badge on it.  Came with this server case I bought for $10, and I didn't even realize the PSU was desirable til I brought it home and noticed 'Hey, this looks like a good piece of kit'.
Title: Subjects more confusing than Alps switches
Post by: typo on Fri, 18 March 2011, 21:07:20
things are only hard to understand if you do not understand them lol.

i will say, the psu being described in the first post is one you do not want. the way the author describes it as being bettered is of course desirable.

the post with the anaology of the train seems to be written in plain laymans terms.

the psu post would be for people that have a background in ee i suppose.
Title: Subjects more confusing than Alps switches
Post by: typo on Sat, 19 March 2011, 00:28:32
as usual, lol ripster!
Title: Subjects more confusing than Alps switches
Post by: crowstar on Sat, 19 March 2011, 05:51:58
Double slit experiment. Google for the dr quantum animation, although simple, it has that wtf is the world feeling