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- One thing I've learned...stick to your guns.
--Wtshymanski 17:47, 24 July 2007 (UTC)
Mains power systems
OK, what exactly in Liberia am I supposed to look at as referenced in your edit summary? Further, how do you figure the text does not violate the policy of WP:NOTHOWTO, and since it is unreferenced WP:V? Or are you going with the thread on the talk page, which would violate WP:OR? Also, please not that Misplaced Pages fails as a WP:RS, so we cannot reference articles with Misplaced Pages references. Thanks. Aboutmovies (talk) 15:59, 29 October 2008 (UTC)
- Oh you horrible little man. Go away. Liberia had a civil war, you know, and it did destroy their electrical infrastructure. Go fix a Pokemon article. --Wtshymanski (talk) 00:38, 30 October 2008 (UTC)
- Excuse me? Not only at this point are you exercising ownership of the article, but now you are being incivil and have leveled a personal attack. Please reconsider your actions and remove your comment here, and revert at the article. Aboutmovies (talk) 04:18, 30 October 2008 (UTC)
Power factor
I would like to learn more about your ideas regarding the range of Power Factor, which I have always understood to be a value between -1 and 1. My impression is that you believe the correct range for Power Factor is between 0 and 1. Could you explain more? Your range puzzles me, because power factor is usually considered to be the ratio of watts (measured over some integer number of periods) which of course can be either positive or negative, to volt-amps (measured over the same number of periods), which is by definition positive.
I note your comment that "power flows in both directions", which is of course true for instantaneous power. But when we are discussing power factor, the power we are concerned with is the average power, which is instantaneous power averaged over an integer number of periods -- the Misplaced Pages article correctly shows this as a horizontal pinkish line in its graphs. Average power is usually positive, i.e. it usually flows from the nominal source to the nominal load. But it certainly can be negative - if you're not sure about this, just do a quick calculation of watts with 180 degrees between the voltage and current waveforms. Indeed, with the increasing number of microgenerator sources in the grid (photovoltaic, etc.), it is becoming more common for the power that flows through a revenue meter to be positive during part of the day and all of the night, but negative during the times of day when there is strong solar radiation available. So in the case of true PF=W/VA, W can be positive or negative but never larger than VA, and the correct range for PF is -1 to 1.
Is there any possibility you were confused by the terminology used back when displacement power factor dPF=cosine(angle between voltage and current) was commonly used? dPF is equal to true PF if both the voltage waveform and the current waveform are sinusoidal. These days, there are so many non-linear loads that the current is often highly distorted, so true PF is a much better measure for most purposes. (dPF is still the correct measurement to use if, and only if, you are choosing the size of power factor correction capacitors.) The possible confusion, in dPF, is that it was conventional to use a "+" or a "-" to indicate leading or lagging - somewhat misleading and mathematically inaccurate, of course, because it made the assumption that the power flow was in the expected direction. But, for dPF, it was a good enough assumption from the 1920's through the 1980's or so.
Some background (so you don't dismiss me as a crank!): I am the President of Power Standards Lab in California, the author of the Electric Power Measurements article in the Encyclopedia of Electrical Engineering, a Senior Member of the IEEE, the author of various texts on measurements in the electric power grid, etc., so I am at least a little familiar with this topic. With best wishes - Alex McEachern AMcEachern (talk) 15:19, 14 December 2008 (UTC)
- Responses at Mr. McEachern's talk page, though regrettably he seems to have gotten discouraged and left.
Merges
I opened a thread at talk:IBM PC-DOS; please discuss there before merging IBMBIO and IBMDOS. Thanks, JeremyMcCracken (talk) (contribs) 20:20, 11 January 2009 (UTC)
- These still look like candidates to merge to me. --Wtshymanski (talk) 21:26, 16 January 2009 (UTC)
Thury
Thanks Bill. At least I know now that one person read it, and can appreciate his significance. I think I'd like this guy if I worked with him. Pragmatic, alert towards opportunities and stubborn.
He was one of many under appreciated engineer inventors whose story and significance is now only beginning to be understood. Another guy is the Russian fellow- Pavel Yablochkov who figured out how to use AC to run multiple arcs off a single generator. The interesting part was that he understood the potential of transformers because he employed an induction coil in his system. So when some hobbyist guys get a hold of his system and do a multiple mile test in London, we have the first case of long distance ac system employing a transformer to change voltages. I think I put that story in the history of electricity transmission article. To be accurate, I believe Yablochkov was using the coil to step up rather than step down the voltage. What would be really interesting is if it came out that George Westinghouse took a close look at it and understood why he needed to get Stanley working on transformers, and why Tesla's step up transformers would be exceptionally valuable.
That's the frequent pattern with invention. One guy takes it a small step, and another sees broader uses and expands the application. Kind of like how a steam engine and the industrial revolution came about due to a guy named Thomas Savery who was only interested in removing water from mines. -J JMesserly (talk) 21:56, 22 January 2009 (UTC)
NTSC
Thanks for the note. While the article has improved considerably in scope, I still think there are some problems with the article structure and tone. There's a lot of very technical information that should probably be confined to the Technical Details section, and a good portion of the article uses informal voice ("This is done by...", "You could think of it as...", etc.) The content on the whole is really good, it just needs some formalization. :) I've left the tag for now, but keep up the good work! //Blaxthos ( t / c ) 23:56, 25 January 2009 (UTC)
Is there a good place elsewhere to put the Color Encoding section you deleted from NTSC? Should it have its own article? Seems a shame to just lose it. Also, see the discussion at Talk:NTSC#NTSC_is_just_a_colour_encoding_system!. — Wdfarmer (talk) 14:54, 4 March 2009 (UTC)
- I should have left a note in the edit summary - I thougt it fit very well in to Color television so that's where the comparision of the different standards went. --Wtshymanski (talk) 15:13, 4 March 2009 (UTC)
Please take a look at the Stray voltage article
(This is being CC'd to both Wtshymanski's and Plugwash's talk.) :-)
Due your background in electrical systems I think you could provide valuable edits to the Stray voltage article, which is just a mess right now. I am trying to put in some objective science discussion of eddy currents, inductive heating, capacitive coupling, ground loops, etc, but it really needs more work. I will dig through my public domain Hawkins/Audels illustration collection to see if I can help flesh out the science better. DMahalko (talk) 19:55, 6 February 2009 (UTC)
Scattershot
On 16 Mar you posted this message to user Armstrong113149:
- Rather than tagging a whole bunch of articles, it would be more useful for Wikiproject Electronics to fix really bad articles such as Semiconductor and Zener diode or even Transistor. Any of these needs far more attention than Incandescent light bulb which has pretty good descriptions of operation, history, and references. --Wtshymanski (talk) 14:25, 16 March 2009 (UTC)
- Agreed, however before I focused my energies on specific articles I wanted to take a wider snapshot of where wikipedia was with regards to electronics. Perhaps we could work together. Do you have a particular article in mind. Regards Armstrong1113149 (talk) 16:11, 16 March 2009 (UTC)
- Start with Semiconductor, Transistor, Zener diode, Integrated circuit, Electronics. Get the core articles on the topic into a readable form (better than a C-student's grade-school essay) first before tagging peripheral topics.
- I'm skeptical of the whole "wikiproject" notion since I've often seen tags added announcing a brave new project and that is the last contribution the "project" members make to the article. Misplaced Pages doesn't need more tags. Misplaced Pages needs spelling checks, fact checks, references, organization -- good writing, not "slacktivism". Some people like to put "physics" tags on everything in sight, too -- also with no effect. In my opinion no matter how good I may feel about scattergunning tags across hundreds of articles, that's not nearly as valuable to the project as working on one or two articles and adding actual content.--Wtshymanski (talk) 16:24, 16 March 2009 (UTC)
- Agreed, however before I focused my energies on specific articles I wanted to take a wider snapshot of where wikipedia was with regards to electronics. Perhaps we could work together. Do you have a particular article in mind. Regards Armstrong1113149 (talk) 16:11, 16 March 2009 (UTC)
I've been working on Zener diode User:Armstrong1113149/Sandbox_1. It's about 50% complete, please review and comment Armstrong1113149 (talk) 03:44, 19 March 2009 (UTC)