Strange idea..
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From: Jan Panteltje on 12 Jul 2010 19:38 PS I wrote: >OK, let me try to explain my way of thinking, maybe bit vague for some, >but it goes like this: >It is much easier to keep a pendulum going then moving it fast left to right >or forward backward, takes less energy. >I like resonant, way of least resistance. >As you have capacitance in the transformer windings plus lots of other places, >why not make use of it and tune things. To clarify things some more, for example IIRC in the TV the HV coil is tuned to the 3rd harmonic of the H frequency, 3 x 15625 Hz.
From: Grant on 12 Jul 2010 20:14 On Mon, 12 Jul 2010 13:02:39 -0500, "Tim Williams" <tmoranwms(a)charter.net> wrote: >"Jan Panteltje" <pNaonStpealmtje(a)yahoo.com> wrote in message news:i1fkaj$9l$1(a)news.albasani.net... >> OK, I was getting the wrong impression perhaps because you marked it as >> '1 W'. >> As for the high voltage, I had (or have?) a lot of those TV H output >> transistors, BU208 and things like that. >> They are great, 700V Vce or more. > >Oddly, I recently tried making an absurdly high ratio boost converter with a 2SC5404 (same old 10A 1.5kVcbo thing). It was avalanching at only 300V. I think this was because I wasn't driving the base negative, only "off" (shunted to GND with a power MOSFET). > >I replaced it with an 800V MOSFET, which dutifully went right up to 820V peak. Not a bad ratio for a 16V supply. > >>>Snubbers are OK to skip where there's a lot of capacitance. This = >>>effectively makes a "lossless" snubber. The downside is, it gets very = >>>frequency sensitive (think induction heater), or draws lots of reactive = >>>current (bad for caps), or something like that. >> >> But much better to tune the thing? >> Square waves radiate a lot... > >Tune? > >BTW, you might want to check your newsreader's settings. In previous posts, you've mentioned an interest in the workings of Usenet so I'm guessing you'll be interested. > >Take the above quote for instance, it has been erroneously appended with equals signs. I'm guessing the encoding isn't set correctly. If it were, either the equals wouldn't be placed, or my newsreader would remove them appropriately. > >In other passages (like the second line of your first quote in this message), your random-length lines wrap at inopportune points, resulting in ugly paragraphs. > >I don't have a clue how my posts (quoted-printable encoding) appear to other newsreaders; in my own, they wrap to the window width, which is perfectly readable. AlwaysWrong seems to object as if they don't wrap at all; maybe he has to read them with a horizontal scroll bar. In his case, I consider that an advantage... but I wonder about others. They wrap to screen here if I turn on wrap option, right now they're going past end of screen since I set 250 char line width for posting to a place that requires no line wrapping sometimes ;) > >I do know that some newsreaders (including OE) have trouble quoting "quoted-printable" (which seems rather ironic). The "> " marks don't get added automatically, which is annoying. I'm curious how this will look without my usual manual newlines ;) Pardon the interruption... Grant. > >Tim
From: Jim Thompson on 12 Jul 2010 20:17 On Tue, 13 Jul 2010 10:14:16 +1000, Grant <omg(a)grrr.id.au> wrote: >On Mon, 12 Jul 2010 13:02:39 -0500, "Tim Williams" <tmoranwms(a)charter.net> wrote: > >>"Jan Panteltje" <pNaonStpealmtje(a)yahoo.com> wrote in message news:i1fkaj$9l$1(a)news.albasani.net... >>> OK, I was getting the wrong impression perhaps because you marked it as >>> '1 W'. >>> As for the high voltage, I had (or have?) a lot of those TV H output >>> transistors, BU208 and things like that. >>> They are great, 700V Vce or more. >> >>Oddly, I recently tried making an absurdly high ratio boost converter with a 2SC5404 (same old 10A 1.5kVcbo thing). It was avalanching at only 300V. I think this was because I wasn't driving the base negative, only "off" (shunted to GND with a power MOSFET). >> >>I replaced it with an 800V MOSFET, which dutifully went right up to 820V peak. Not a bad ratio for a 16V supply. >> >>>>Snubbers are OK to skip where there's a lot of capacitance. This = >>>>effectively makes a "lossless" snubber. The downside is, it gets very = >>>>frequency sensitive (think induction heater), or draws lots of reactive = >>>>current (bad for caps), or something like that. >>> >>> But much better to tune the thing? >>> Square waves radiate a lot... >> >>Tune? >> >>BTW, you might want to check your newsreader's settings. In previous posts, you've mentioned an interest in the workings of Usenet so I'm guessing you'll be interested. >> >>Take the above quote for instance, it has been erroneously appended with equals signs. I'm guessing the encoding isn't set correctly. If it were, either the equals wouldn't be placed, or my newsreader would remove them appropriately. >> >>In other passages (like the second line of your first quote in this message), your random-length lines wrap at inopportune points, resulting in ugly paragraphs. >> >>I don't have a clue how my posts (quoted-printable encoding) appear to other newsreaders; in my own, they wrap to the window width, which is perfectly readable. AlwaysWrong seems to object as if they don't wrap at all; maybe he has to read them with a horizontal scroll bar. In his case, I consider that an advantage... but I wonder about others. > >They wrap to screen here if I turn on wrap option, right now they're going past end of screen since I set 250 char line width for posting to a place that requires no line wrapping sometimes ;) >> >>I do know that some newsreaders (including OE) have trouble quoting "quoted-printable" (which seems rather ironic). The "> " marks don't get added automatically, which is annoying. > >I'm curious how this will look without my usual manual newlines ;) > >Pardon the interruption... > >Grant. >> >>Tim There should be a wrap setting in your newsreader, in the same section where you set quote (>>>) marks. ...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 | Obama isn't going to raise your taxes...it's Bush' fault: Not re- newing the Bush tax cuts will increase the bottom tier rate by 50%
From: m II on 12 Jul 2010 21:10 Tim Williams wrote: > And apparently Tesla himself was convinced of this fallacy. I'd like to read the his views on that. He doesn't seem the type to be easily duped. I know he felt there was an 'aether' permeating the universe, but that isn't such a big sin. mike
From: Grant on 12 Jul 2010 21:41
On Mon, 12 Jul 2010 17:17:32 -0700, Jim Thompson <To-Email-Use-The-Envelope-Icon(a)On-My-Web-Site.com> wrote: .... >There should be a wrap setting in your newsreader, in the same section >where you set quote (>>>) marks. Yes, I have it set to 250 to suit another place (lkml) ;) Even though Linux CodingStyle specifies max 80 char lines, if somebody exceeds it, one cannot rewrap that line, as the meaning of the code would change. I'm quite happy putting in manual newlines, been doing that writing code for so many years, it is second nature ;) Occasionally I'll break the convention on Usenet when reporting or responding to stuff that exceeds 80 cols and looks totally messed up if line-wrapped. Current nature of usenet is pretty messed up anyway, probably because self-moderation doesn't exist for lot's of people? Grant. |