User talk:Spinningspark/Archive 6

Re: Hooks are for catching, articles are for explaining

Sure. You can just ignore my comments and wait for others. DYK is much about sense of phrasing, which is an art I haven't mastered. You probably know that DYK admins rewrite most hooks before launching. One of my hooks was completely replaced by another fact in the article in the last moment before launch. As to my mocking at DYK, it had its grounds ;-) Getting serious, I think the article title should be changed. "On copper lines" is a slang on its own, electronics uses that for bare copper lines on printed boards, and I would use something like "in electrical cables". To you, reflections refer to electrical signals, but my immediate reaction was reflection of light (I'm sure some people think of sound instead - that is why my comment on ringing). "High-frequency noise" is more neutral than ringing, but again, if you want a mystery in the hook .. Materialscientist (talk) 07:54, 27 August 2009 (UTC)

Sorry for bothering. Just a thought. "Signal reflections on electrically conducting lines" may refer and does refer to any signal (acoustic, optical, radio, whatever) and "on" to me sounds like an external wave (propagating somewhere) crossed the cable and interacted with it. I imagine usual several power cables running parallel to the ground, acting like diffraction grating to incoming radiowaves. Materialscientist (talk) 08:06, 27 August 2009 (UTC)

I chose the article title on the grounda that Wikipedia follows the common name of a thing and "copper lines" is certainly the common name. It might be informal and slightly inaccurate but it is not exactly slang. "Reflections on tranmsission lines" is no good as it includes waveguides and fibre-optics which are outside the scope and if I call it that we will get the analogue filter argument all over again. "Reflections on electrical transmission lines" is possible but still arguably including waveguides. Your suggestion of "...in electrical cables" excludes stripline and microstrip formats which are definitely within the scope of the article. Without going to something utterly cumbersome like "signal reflections on electrical transmission lines consisting of electrical conductors", I think "reflections on copper lines" is a good compromise which nails precisely what is being discussed to the reader. The job of the title is to allow the reader to choose the right article from amongst reflection (mathematics), reflection (linear algebra), reflection (computer science), reflection (physics) or even reflection (electrical) and with this title there is little danger the reader will go to the wrong one. SpinningSpark 11:05, 27 August 2009 (UTC)

Two questions, (i) why "on" not "in" ? Consider "light scatters on a waveguide" and "light scatters in a waveguide" To me, first means light traveled through space, met a waveguide and scattered on it, second means light propagated through a waveguide and scattered on its way. (ii) why copper? I understand it is a common slang, but copper is only one cable (or strip) material. Why not "(signal) reflections in conducting lines" ? Materialscientist (talk) 12:10, 27 August 2009 (UTC)

"in" is acceptable but "on" is definitely the more common expression in this context. Why? there is no why; it's just one of those perverse idioms of English. We can be on form but later in decline; you might be instructed to do something "when you are in receipt..." but "you should, on receipt, ...". The "up" and "down" conventions are even worse: we cut down trees, but then chop them up; after dinner we wash up, but to get rid of the suds we rinse down. I could go on, but the short answer is I don't know why. I know copper is not the only material, but that is the common expression, especially when disambiguating against fibre-optic. The reason here is obvious - it is by far the most common metal used for cables. I don't really care if the article title gets changed, but this is what I think it should be. SpinningSpark 12:34, 27 August 2009 (UTC)

Yes, idioms are a nightmare of foreign language. BTW, would it be correct to say that "My reflections on copper wires" means "My thoughts about copper wires" ? I trust you know terminology of your field and leave this with you. My message above was only to say that in my field, "reflection on" and "reflection in" have different and geometry related (rather than idiomatic) meanings. Materialscientist (talk) 22:10, 27 August 2009 (UTC)

My reflections on copper wires, yes you are absolutely right, are you going to write that article? It will go with reflections on the Guillotine, an article about how shiny it is. SpinningSpark 23:29, 27 August 2009 (UTC)

I was eager to, but you took that from me by your Reflections on copper lines ;-). Materialscientist (talk) 23:41, 27 August 2009 (UTC)

Just a thought

Have you considered bringing copper to GA nomination? WP:Elements would only be grateful for that as the activity there dropped to nearly zero during the last few month. As far as can see, no-one is developing this article. I thought it could be a nice refreshment after electrical circuits. Materialscientist (talk) 23:39, 29 August 2009 (UTC)

I'm more than willing to assist with a GA nomination. I would not want to take the lead though, ie somone else should nominate it, many areas of that article are well outside my area of expertise. SpinningSpark 23:49, 29 August 2009 (UTC)

That is my point - to get out of "your areas of expertise" and nominate yourself. I was first scared to do so too, but came over. I know no-one on WP who can cover professionally all aspects of any elements article, which has not been a problem. I will help. Materialscientist (talk) 23:56, 29 August 2009 (UTC)

Don't really want to take on any more right now. I want to have another crack at getting Otto Zobel through FA first. SpinningSpark 00:07, 30 August 2009 (UTC)

DYK for Primary line constants

On August 30, 2009, Did you know? was updated with a fact from the article Primary line constants, which you created or substantially expanded. You are welcome to check how many hits your article got while on the front page (here's how) and add it to DYKSTATS if it got over 5,000. If you know of another interesting fact from a recently created article, then please suggest it on the Did you know? talk page.

— Jake Wartenberg 11:15, 30 August 2009 (UTC)

DYK for Reflections on copper lines

On August 30, 2009, Did you know? was updated with a fact from the article Reflections on copper lines, which you created or substantially expanded. You are welcome to check how many hits your article got while on the front page (here's how) and add it to DYKSTATS if it got over 5,000. If you know of another interesting fact from a recently created article, then please suggest it on the Did you know? talk page.

— Jake Wartenberg 11:15, 30 August 2009 (UTC)

You seem rather lonely so...

..hi. Lord Spongefrog, (I am a flesh-eating robot) 19:02, 30 August 2009 (UTC)

Always listen to Lord Sponge a.k.a. Spfizzilizounge. But if you want one more, make a page with all the reasons why you should have them - and I'll give you the shame barnstar for it. :) Lord Spongefrog, (I am a flesh-eating robot) 19:12, 30 August 2009 (UTC)

Filter (signal processing)

Not a bad article, but are we sure we really need a new one? And after all my decades in signal processing, I've never used, or even much heard, the term "wave filter". It seems like a rather obsolete term (I do find it defined in the BSTJ in 1922). I'm not sure what other term would commonly fill in for this concept, other than just "linear filter", but I don't think we should give some prominence to a term so little used (see these few books). Dicklyon (talk) 22:35, 30 August 2009 (UTC)

On the first point, there is no doubt in my mind that we need this article. A top level filter article is needed which can then refer down to all the other filter articles in an organised way. This article used to exist years ago but was merged into electronic filter because it was very lightweight. Ever since then "electronic filter" has been the de facto top level article and has accumulated all kinds of inappropriate material. There has been sporadic debates on this on the talk pages, usually concluding that this is bad but no action ever been taken. So I was bold ... but truth be known, I think there is still a lot of material in "electronic filter" that should be elsewhere but did not want to be too drastic as a first step, just establish the existence of "filter (signal processing)".

On "wave filter" you are absolutely right, this is my bad, the term is completely obsolete. I have been writing a lot of articles on the "image filter" era and have been wading through endless papers and patents that all use this term and it kind of got ingrained. However, there is a need to distinguish frequency filtering filters from those filtering something else - but what to call them? Aye there's the rub. SpinningSpark 22:54, 30 August 2009 (UTC)

Very interesting stuff, now that I see what you've been up to. I've been doing a bit of related work myself recently (not in WP), on auditory filter models related to the non-uniform wave propagation system of the cochlea (actually, not just recently, but for over 30 years, but with a new spin). Yet somehow I had missed a lot of that old filter theory. I have been very aware of the transmission-line cochlea-model circuits of Wegel and Lane (1924), Peterson and Bogert (1950), etc., but hadn't really read the AT&T origins of transmission-line-based filters; very interesting and useful stuff, actually. It's cool how Campbell discovered that a loaded line makes a good lowpass filter. By the way, since you're an old (I'm guessing) British telecomms engineer, maybe you know my old buddy Colin M. of BT (last name by email on request) who spent the summer of '73 with me working at Bell Labs Holmdel. My immediate interest is to make a good procedure to go from the exponential description of a transmission line to a good section rational transfer function to make a cascade-form filter out of; not for sharp cutoff, but for a nice pseudo-resonant response to model the cochlea. The math looks like it might come out pretty simple. I haven't seen anything like that; let me know if you have any pointers to relevant art.

As for what to call them, I'd just say continuous-time linear filters, since that's what sinusoids (or complex exponentials, really) are the eigenfunctions of. Dicklyon (talk) 04:01, 31 August 2009 (UTC)

No, I am not BT, my background is the broadcast and military-aerospace industries. I only know the transmission line model of the ear in broad outline so am probably not going to be much help, but for what its worth, here are my thoughts. My gut feeling is that image filters based on the Campbell model are not going to be much use to you. The original Campbell filter is reasonably well behaved, but most of the subsequent development was aimed at improving the cut-off with no regard to how badly that mangled the phase response - which it did. Plus, there are theoretical flaws in the image method which is what led to it being abandoned - experience is needed to know what is, and is not, going to work. You are right though, that calculation is particularly simple, which is why the method stayed in use long after better techniques came along, an important consideration pre-internet era. What may be of use to you is the classic image era method of constructing artificial lines was with lattice filter sections. This idea originated (I think) with Bartlett but was much developed at Bell Labs. I have to hand some patents of Zobel on this subject (see particularly US1760973), doubtless he published in BSTJ as well but I don't have any references (edit: there is also G. W. Pierce's artificial delay lines for use with sonar). I am presuming you are looking at digital implementations here, but if you are not, here's another idea. If you frequency shift your signal up to somewhere in SHF microwaves you will be able to construct you model with real transmission lines in a reasonably small space using, say, stripline technology. There is no shortage of material on design of filters in this area.

I saw your comment on the "strange redirect" at analogue filter. The history of that is that I wrote a major expansion of the original stubby article, but was asked to change the name at GA review because there was not enough material in it on active implementations. I would like to see it moved back at some stage, but I'm not going to touch it for fear of starting another argument. It seems every article I write nowadays triggers a dispute over the title and I'm getting paranoid about it. You are not helping with "wave filter" -:) I am wondering if I am speaking a different language; maybe there should be a wiki for daft old timers who refuse to use modern terminology. SpinningSpark 10:13, 31 August 2009 (UTC)

In regard to the last post in your Archive 5...

Munich calling? Are you some sort of German spy? Lord Spongefrog, (I am a flesh-eating robot) 20:02, 31 August 2009 (UTC)

If I was do you suppose I would tell you? So either way die Antworte ist nein the answer is no. SpinningSpark 20:09, 31 August 2009 (UTC)

Ich glaube Sie nicht. Sie sind ein Spion. Lord Spongefrog, (I am a flesh-eating robot) 20:18, 31 August 2009 (UTC)

Changed my mind. Your German masters would most likely choose a better place than Wikipedia to make communications. Lord Spongefrog, (I am a flesh-eating robot) 20:25, 31 August 2009 (UTC)

Talkback

Hello, Spinningspark. You have new messages at Ron Ritzman's talk page.
You can remove this notice at any time by removing the {{Talkback}} or {{Tb}} template.

Ron Ritzman (talk) 13:17, 4 September 2009 (UTC)

Sorry

Sorry about that. I will remove the comment. I removed your comment on my talk page. My mistake. Ikip (talk) 14:58, 6 September 2009 (UTC)

It's definitely not you!

		The Barnstar of Liberty
		For your willingness to stand for truth and get to the point. Firefly322 (talk) 17:27, 7 September 2009 (UTC)