Let's Take A Vote...
in [Design]
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From: John Fields on 26 Jul 2010 15:37 On Mon, 26 Jul 2010 09:57:07 -0700, Jim Thompson <To-Email-Use-The-Envelope-Icon(a)On-My-Web-Site.com> wrote: >On Sun, 25 Jul 2010 18:09:32 -0700, Jim Thompson ><To-Email-Use-The-Envelope-Icon(a)On-My-Web-Site.com> wrote: > >>On Sun, 25 Jul 2010 20:04:07 -0500, John Fields >><jfields(a)austininstruments.com> wrote: >> >>>On Sun, 25 Jul 2010 12:40:12 -0700, John Larkin >>><jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >>> >>>>On Sun, 25 Jul 2010 13:26:21 -0500, John Fields >>>><jfields(a)austininstruments.com> wrote: >>>> >[snip] >>>>> >>>>>"The Moving Finger writes; and, having writ, >>>>> Moves on: nor all thy Piety nor Wit >>>>>Shall lure it back to cancel half a Line, >>>>> Nor all thy Tears wash out a Word of it." >>>>> >>>>> >>>>>From Edward Fitzgeralds's translation of the >>>>>Rub�iy�t of Omar Khayy�m. >>>> >>>>I guess you didn't read the wiki article. I pointed you at the easiest >>>>part. >>>> >>>>http://en.wikipedia.org/wiki/Dimensional_analysis#Commensurability >>> >>>--- >>>I read it, but it seems you're trying to prove whatever your point is >>>by grasping at straws. >>> >>>Can the force between like charges not be determined by the magnitude >>>of the charge(s) and the separation between them? >>> >>>JF >> >>Careful there John Fields, Phil Hobbs will plonk you... like you could >>care :-) --- Phil Hobbs??? Don't you mean John Larkin? --- >>I think I still have the whole thread in "Trash", since I haven't >>emptied it for awhile. I'll track down the "force" discussion. >> >> ...Jim Thompson > >John F, I've just E-mailed you the portions of the thread that contain >the word "force", with headers. So you can peruse it and find what >you need. > > ...Jim Thompson --- Thanks!
From: Jim Thompson on 26 Jul 2010 18:49 On Mon, 26 Jul 2010 14:37:49 -0500, John Fields <jfields(a)austininstruments.com> wrote: >On Mon, 26 Jul 2010 09:57:07 -0700, Jim Thompson ><To-Email-Use-The-Envelope-Icon(a)On-My-Web-Site.com> wrote: > >>On Sun, 25 Jul 2010 18:09:32 -0700, Jim Thompson >><To-Email-Use-The-Envelope-Icon(a)On-My-Web-Site.com> wrote: >> >>>On Sun, 25 Jul 2010 20:04:07 -0500, John Fields >>><jfields(a)austininstruments.com> wrote: >>> >>>>On Sun, 25 Jul 2010 12:40:12 -0700, John Larkin >>>><jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >>>> >>>>>On Sun, 25 Jul 2010 13:26:21 -0500, John Fields >>>>><jfields(a)austininstruments.com> wrote: >>>>> >>[snip] >>>>>> >>>>>>"The Moving Finger writes; and, having writ, >>>>>> Moves on: nor all thy Piety nor Wit >>>>>>Shall lure it back to cancel half a Line, >>>>>> Nor all thy Tears wash out a Word of it." >>>>>> >>>>>> >>>>>>From Edward Fitzgeralds's translation of the >>>>>>Rub�iy�t of Omar Khayy�m. >>>>> >>>>>I guess you didn't read the wiki article. I pointed you at the easiest >>>>>part. >>>>> >>>>>http://en.wikipedia.org/wiki/Dimensional_analysis#Commensurability >>>> >>>>--- >>>>I read it, but it seems you're trying to prove whatever your point is >>>>by grasping at straws. >>>> >>>>Can the force between like charges not be determined by the magnitude >>>>of the charge(s) and the separation between them? >>>> >>>>JF >>> >>>Careful there John Fields, Phil Hobbs will plonk you... like you could >>>care :-) > >--- >Phil Hobbs??? > >Don't you mean John Larkin? You mean you missed this... [Begin quoted thread] "Jim Thompson wrote: > On Sun, 25 Jul 2010 18:34:31 -0400, Phil Hobbs > <pcdhSpamMeSenseless(a)electrooptical.net> wrote: > >> Jim Thompson wrote: >>> On Sun, 25 Jul 2010 21:53:36 +0100, John Devereux >>> <john(a)devereux.me.uk> wrote: >>> >>>> Jim Thompson <To-Email-Use-The-Envelope-Icon(a)On-My-Web-Site.com> writes: >>>> >>>>> On Sun, 25 Jul 2010 12:25:02 -0700, John Larkin >>>>> <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >>>>> >>>>>> On Sun, 25 Jul 2010 11:02:46 -0700 (PDT), Nunya >>>>>> <jack_shephard(a)cox.net> wrote: >>>>>> >>>>>>> On Jul 25, 10:10 am, John Larkin >>>>>>> <jjlar...(a)highNOTlandTHIStechnologyPART.com> wrote: >>>>>>>> On Sun, 25 Jul 2010 09:55:35 -0700 (PDT), Nunya >>>>>>>> >>>>>>>> <jack_sheph...(a)cox.net> wrote: >>>>>>>> >>>>>>>>> Nobody said that coulombs were a measure of force. >>>>>>>> John Fields said precisely that, which was what started this whole >>>>>>>> series. >>>>>>>> >>>>>>>> John >>>>>>> They can be a measure of proof that force was applied, and >>>>>>> that can be quantified with certain devices, such as capacitors. >>>>>>> You lose, again. >>>>>> Word salad, again. >>>>>> >>>>>> John >>>>> John "The Bloviator" Larkin obfuscates yet again. Where's the "meat", >>>>> John? You can't deliver, so you bloviate. >>>> Oh, give it a rest Jim. >>> Larkin can "give it a rest" simply by withdrawing his asinine >>> statement. But he won't... ever. John "The Bloviator" Larkin is >>> totally incapable of admitting error. >>> >>>>> Anyone here EVER seen real numbers from John "The Bloviator" Larkin? >>>> Of course, many times. He frequently posts circuit measurements for >>>> but one example. >>>> >>>>> Speak up if you think you have. >>>>> >>>>> ...Jim Thompson >>> On components. When has John "The Bloviator" Larkin ever presented a >>> circuit with values AND performance specified? >>> >>> ...Jim Thompson >> Tiresome. Very tiresome. I'd really hate to have to killfile you, Jim, >> but I'm getting close. >> >> Cheers >> >> Phil Hobbs > > Go ahead. > > Did not John err in his "charge is not conserved" statement? > > But I guess you're not interested in _factual_ discussions, just BS > ones ?? > > ...Jim Thompson You won't catch this trout with that wilted bit of bait. Not the whitelist, the kill file. A small select group--even Mr. Many Nyms isn't in it. Sayonara. Phil Hobbs -- Dr Philip C D Hobbs Principal ElectroOptical Innovations 55 Orchard Rd Briarcliff Manor NY 10510 845-480-2058 hobbs at electrooptical dot net http://electrooptical.net" [End quoted thread] Don't you get a kick about the "trout" ?:-) Mustn't catch up anyone in FACTS. Phil defends the Larkin village-idiot repeatedly. At first I thought it was a financial arrangement... Phil was on Larkin's payroll. Now, I'm beginning to wonder... all the folderol over the "young bucks" makes me wonder if there isn't some other relationship :-) [snip] No one seems to care that I have a full (lengthy) website page devoted to WORKING circuits I've posted to SED. I've been a subscriber and occasional poster to the LTspice List. No nonsense there, Helmut won't put up with it. With this group dominated by bloviating village idiots and pompous PhD's, maybe I should just pull a "Woodgate" and walk away from here and spend more of my time with LTspice... no one here would notice... SED is really now below SEB in technical content... and readership and authors. ...Jim Thompson -- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | Spice is like a sports car... Only as good as the person behind the wheel.
From: Nunya on 26 Jul 2010 18:58 On Jul 26, 12:37 pm, John Fields <jfie...(a)austininstruments.com> wrote: > On Mon, 26 Jul 2010 09:57:07 -0700, Jim Thompson > > > > <To-Email-Use-The-Envelope-I...(a)On-My-Web-Site.com> wrote: > >On Sun, 25 Jul 2010 18:09:32 -0700, Jim Thompson > ><To-Email-Use-The-Envelope-I...(a)On-My-Web-Site.com> wrote: > > >>On Sun, 25 Jul 2010 20:04:07 -0500, John Fields > >><jfie...(a)austininstruments.com> wrote: > > >>>On Sun, 25 Jul 2010 12:40:12 -0700, John Larkin > >>><jjlar...(a)highNOTlandTHIStechnologyPART.com> wrote: > > >>>>On Sun, 25 Jul 2010 13:26:21 -0500, John Fields > >>>><jfie...(a)austininstruments.com> wrote: > > >[snip] > > >>>>>"The Moving Finger writes; and, having writ, > >>>>> Moves on: nor all thy Piety nor Wit > >>>>>Shall lure it back to cancel half a Line, > >>>>> Nor all thy Tears wash out a Word of it." > > >>>>>From Edward Fitzgeralds's translation of the > >>>>>Rubáiyát of Omar Khayyám. > > >>>>I guess you didn't read the wiki article. I pointed you at the easiest > >>>>part. > > >>>>http://en.wikipedia.org/wiki/Dimensional_analysis#Commensurability > > >>>--- > >>>I read it, but it seems you're trying to prove whatever your point is > >>>by grasping at straws. > > >>>Can the force between like charges not be determined by the magnitude > >>>of the charge(s) and the separation between them? > > >>>JF > > >>Careful there John Fields, Phil Hobbs will plonk you... like you could > >>care :-) > > --- > Phil Hobbs??? > > Don't you mean John Larkin? > --- > > >>I think I still have the whole thread in "Trash", since I haven't > >>emptied it for awhile. I'll track down the "force" discussion. > > >> ...Jim Thompson > > >John F, I've just E-mailed you the portions of the thread that contain > >the word "force", with headers. So you can peruse it and find what > >you need. > > > ...Jim Thompson > > --- > Thanks! See below for something almost as good as the song links... I wonder how much charge is being transferred between these various, separated 'bodies'. Is anything lost between these elements when they transfer "charge" (besides JL)? http://jpeojtrs.mil/files/org_info/OV-1_ver16.pdf Version 16 is a damn sight more complicated than the original plan was. Nobody can complain anymore about cost when they keep piling on complexity. It is getting there, however... It turns out to be the only way to get there after all. It is kind of like Von Braun's decision to use an LOR paradigm for the Moon missions. Turns out the way proposed was the ONLY way, yet it was not *his* way, so he was against it, right up to the last design choice review, and surprised his own team went he agreed to it.
From: George Herold on 26 Jul 2010 22:42 On Jul 26, 2:55 pm, John Larkin <jjlar...(a)highNOTlandTHIStechnologyPART.com> wrote: > On Mon, 26 Jul 2010 11:25:26 -0700 (PDT), George Herold > > > > > > <gher...(a)teachspin.com> wrote: > >On Jul 26, 1:24 pm, John Larkin > ><jjlar...(a)highNOTlandTHIStechnologyPART.com> wrote: > >> On Sun, 25 Jul 2010 20:51:54 -0700 (PDT), George Herold > > >> <gher...(a)teachspin.com> wrote: > >> >On Jul 25, 11:40 pm, John Larkin > >> ><jjlar...(a)highNOTlandTHIStechnologyPART.com> wrote: > >> >> On Sun, 25 Jul 2010 20:14:06 -0700 (PDT), George Herold > > >> >> <gher...(a)teachspin.com> wrote: > >> >> >On Jul 25, 8:54 am, Phil Hobbs > >> >> ><pcdhSpamMeSensel...(a)electrooptical.net> wrote: > >> >> >> George Herold wrote: > >> >> >> >>>> John > >> >> >> >>>> [1] extra credit: how big would they be? > >> >> >> >> Objects have both self-capacitance and mutual capacitance, so it's quite > >> >> >> >> sensible to talk about a capacitor with only one lead. In Gaussian > >> >> >> >> units, the self-capacitance of an isolated sphere of radius r > >> >> >> >> centimetres is r. (The CGS unit of capacitance is the centimetre.) > > >> >> >> >> One cm ~= 1.12 pF, so 330,000 pF is about 30 km radius. That's quite a > >> >> >> >> big reel! > > >> >> >> >> - Show quoted text - > > >> >> >> > (Or get Phil to check my math.) > > >> >> >> > George H. > > >> >> >> He's having enough trouble with his own recently--it took two tries this > >> >> >> time. > > >> >> >> Cheers > > >> >> >> Phil Hobbs > > >> >> >> -- > >> >> >> Dr Philip C D Hobbs > >> >> >> Principal > >> >> >> ElectroOptical Innovations > >> >> >> 55 Orchard Rd > >> >> >> Briarcliff Manor NY 10510 > >> >> >> 845-480-2058 > >> >> >> hobbs at electrooptical dot nethttp://electrooptical.net-Hidequotedtext - > > >> >> >> - Show quoted text - > > >> >> >My 4*pi was a guess. > >> >> >What's more interesting is the C of an isolated trace with no ground > >> >> >plane near by. (say some high impedance circuit) > >> >> >Do you know how the C scales with the width? Assuming the length is > >> >> >much greater than the width. > > >> >> >George H. > > >> >> Do you mean, like, a microstrip trace on an FR4 board with no ground > >> >> plane anywhere? Like all such problems, it's messy. If the trace is > >> >> narrow compared to the dielectric thickness, Er is midway between > >> >> FR4's (around 4.6 maybe) and air. If the trace is much wider, Er > >> >> approaches 1. > > >> >> I have tools to compute L and C per unit length for the common cases, > >> >> microstrip with ground plane, stripline, CPW, things like that. Your > >> >> case isn't among them. Easier to measure... if you can decide what to > >> >> measure *to* > > >> >> I think Wadell's book covers that case, but his book is pretty much > >> >> unusable. He has equations that cover a full page, and they include > >> >> terms that themselves occupy other pages. > > >> >> John- Hide quoted text - > > >> >> - Show quoted text - > > >> >Oh, I was thinking about my question, ... Well first it should scale > >> >with the length of the trace. (that's pretty obvious) And then I > >> >thought there should be some logaritham(sp) of the width vs some other > >> >distance... But I couldn't think what distance. It must be the > >> >distance from the trace to where ever the nearest ground is... perhaps > >> >the walls of the metal box enclosing it. > > >> >I wasn't thinking about the dielectric. That should be a secondary > >> >effect... as long as the distance to the walls is a lot more than the > >> >dielectric thickness. > > >> >George H. > > >> I checked: Wadell does a lot of weird cases, but not a conductor on > >> dielectric and nothing else. His "covered microstrip" equation is 4 > >> pages long! > > >> Look up ATLC, the free transmission-line calculator. It will solve > >> cases like this. > > >> I think that a big grounded box will be the same as free space, as > >> close as any of the tools can usefully resolve. > > >> John- Hide quoted text - > > >> - Show quoted text - > > >Thanks John, I'll see what I find. I really should just do the > >problem for myself from a fundamental physics level. Assume an > >infinite wire of radius R and calculate the capacitance per unit > >length. > > >The 'real' question I have is, does it make sense to make really > >skinny traces for a high impedance circuit with no ground plane? > >Sense in that on want to keep the capacitance low. > > Absolutely. Use the shortest and skinniest traces you can, no planed > nearby, no or tiny vias. > > >OK I got down the "Radio Engineers Handbook" by Terman, from my bosses > >book shelf. (He's an old fart.) Terman does the case of a wire > >diameter d a height h above a ground plane. For h>>d the capacitance > >per foot (in units of micro micro Farads) > >is, > >C = 7.354/log(4h/d) > > Appcad (free from Agilent) does that case, but only gives you Zo and > effective Er. I have a little PowerBasic program that converts those > values to c and l per inch. You're welcome to it. > > Almost any simple equation, like the one above, gets inaccurate at > certain geometries. The classic microstrip equation, like in the Moto > ECL book, reports negative impedance for wide traces. Appcad is pretty > good and will warn you when it isn't. As far as I can tell, many such > equations are basically accidental curve fits, not based on much > actual physics. No, the logarithm is real physics. The E field between concentric cylinders goes as 1/r. Integrating that gives a log of the ratio of radii. (with a minus sign in the exponent.) If I cut the width in half I only get some 30% improvement. Keeping the traces as short as possible is much more important. (I think) George H. > > Another nice program is Txline 2003, which does some cases that Appcad > doesn't. > > I have a bunch of Terman's books, but I am *not* an old fart! Terman > apparently was... read "The Inventor and the Pilot" for some dirt. Really? I'm only 51 or 3? But whatever, I still figure I'm an old fart too. Old fart was mostly meant as a term of endearment. I don't know Terman at all. (should I take the book home for a night or two?) I remembered that JR (my boss) had pulled it off the shelf when Id asked a similar question about the inductance of traces. George H. > John- Hide quoted text - > > - Show quoted text -
From: John Larkin on 27 Jul 2010 10:01
On Tue, 27 Jul 2010 04:00:22 -0500, John Fields <jfields(a)austininstruments.com> wrote: >>It has to do with >>getting SI units right. Did you ever read the wiki piece on >>dimensional analysis? Do you think it is smoke and mirrors? >> >>So, where did I say that charges can't generate forces? If you can't >>find such a statement, YOU are the one with emotions clouding your >>reason. > >--- >Nonsense. > >All it means is that its location has slipped my mind, that the >message has been deleted or, who knows??? Who knows??? I know. You are deluded or just a liar. I would never say anything so silly. John |