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From: John Fields on 18 Mar 2010 09:45 On Wed, 17 Mar 2010 18:42:16 -0700, Jim Thompson <To-Email-Use-The-Envelope-Icon(a)My-Web-Site.com> wrote: >On Wed, 17 Mar 2010 17:56:02 -0700, John Larkin ><jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: > >>On Wed, 17 Mar 2010 16:37:47 -0500, John Fields >><jfields(a)austininstruments.com> wrote: >> >>> >>>>Yes, he and JT are unusually vulgar today. I figure they were cuddling >>>>for warmth and the shawl fell off their knees. >>> >>>--- >>>Geez, John, one of us finding you wrong and the other agreeing with that >>>finding doesn't represent "cuddling" in my book, just statement of, and >>>agreement on, objective fact. >>> >>>Of course being found wrong is "mea maxima culpa" when viewed through >>>your deranged set of values and can't be allowed to coexist with what >>>you hold precious; your infallibility, Mr. "Infinity only means >>>something very large.", so you'll try to do whatever you can to fool all >>>of the people all of the time even though all you do is fool yourself >>>since you think you've gotten everyone to goose-step along with you. >>> >>>JF >> >> >>Let's see, your brilliant corrections include >> >>Disputing whether unboundedly large things can be properly referred to >>as "infinite" >> >>and >> >>Correcting me when I said a divisor can be programmed from 1 to 128, >>without specifying the programming step size. I did say that three >>pins did the selection, which some people would take as a clue. >> >> >>And JT calls me prissy! >> >>John >> > >Would you prefer "pompous" ?:-) --- I'm pretty sure he'd prefer: "Your Majesty". JF
From: Jan Panteltje on 18 Mar 2010 10:05 On a sunny day (Wed, 17 Mar 2010 16:14:09 -0700) it happened "Paul Hovnanian P.E." <Paul(a)Hovnanian.com> wrote in <4BA16241.F0FF0278(a)Hovnanian.com>: >VWWall wrote: >> >> Paul Hovnanian P.E. wrote: >> > Kevin Lang wrote: >> >> What would be the simplest way to derive a simultaneous three phase >> >> output from a sine wave produced by a single function generator IC ... >> >> that does not change as the frequency is varied? >> >> >> >> Specifically, two additional sinewaves remaining 120 and 240 degrees >> >> out of phase with the original as the frequency is varied between >> >> 100Hz and 1KHz. >> >> >> >> Kevin Lang >> > >> > Google "Scott Tee Transformer" and then figure out how to generate a >> > sine wave in quadrature to the reference. >> > >> From my reply in the same thread,3/11/2010 03:03PM: >> >> "Once you've got two sine waves in quadrature, getting three phase is >> simple. Just use a Scott-T transformer. These were once used for power >> applications, but since two phase power is almost extinct, they are now >> used for connecting servos that use synchros to those with resolvers." >> >> http://en.wikipedia.org/wiki/Scott-T_transformer >> >> Glad to see another old time power guy! :-) > >Yeah. These electronic types loose me when they start talking about 61 >Hz or higher. Yes, I remember we had a 50 Hz frequency meter in the lab, it consisted of some metal tongues resonating at 46, 47, 48, 49, 50, 51, etc. Each tongue had the frequnecy written above it. Big thing :-) The one that vibrated the most indicated the frequency. frequency 48 49 50 51 52 = = = = =
From: John Larkin on 18 Mar 2010 10:39 On Thu, 18 Mar 2010 08:41:55 -0500, John Fields <jfields(a)austininstruments.com> wrote: >On Wed, 17 Mar 2010 17:56:02 -0700, John Larkin ><jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: > >>On Wed, 17 Mar 2010 16:37:47 -0500, John Fields >><jfields(a)austininstruments.com> wrote: >> >>> >>>>Yes, he and JT are unusually vulgar today. I figure they were cuddling >>>>for warmth and the shawl fell off their knees. >>> >>>--- >>>Geez, John, one of us finding you wrong and the other agreeing with that >>>finding doesn't represent "cuddling" in my book, just statement of, and >>>agreement on, objective fact. >>> >>>Of course being found wrong is "mea maxima culpa" when viewed through >>>your deranged set of values and can't be allowed to coexist with what >>>you hold precious; your infallibility, Mr. "Infinity only means >>>something very large.", so you'll try to do whatever you can to fool all >>>of the people all of the time even though all you do is fool yourself >>>since you think you've gotten everyone to goose-step along with you. >>> >>>JF >> >> >>Let's see, your brilliant corrections include >> >>Disputing whether unboundedly large things can be properly referred to >>as "infinite" > >--- >Even in the original context, where you claimed that switching relays >exhibit infinite gain, they _cannot_ because the power used to switch >them is non-zero. You must be another nym of AlwaysWrong. He's obscessed with how I use a cleaning machine, and you're obscessed with how I once used the word "infinite." >--- > >>and Correcting me when I said a divisor can be programmed from 1 to 128, >>without specifying the programming step size. > >--- >Well, in reality it was originally: > >"We're using one part that's pin strappable for 8-4-2-1 MHz." But it is strappable for those frequencies. > >Then, when you got called on that it changed to: > >"It's basically an 8 MHz oscillator with three pins that can be strapped >to divide by 1 through 128." > >Now, I know you're from Louisiana, so English isn't your first language, >but when most of the rest of us read: "1 through 128", we generally tend >to include all of the counting numbers between 1 and 128. Not people who can figure out that 3 bits only have 8 states. And anybody who is picky about details can always read the datasheet. > >Just for your future reference, if it's: "1 through 128, inclusive", >that includes the numbers on the ends. And JT calls me prissy! >--- > >>I did say that three >>pins did the selection, which some people would take as a clue. > >--- >And, believing mistakenly that you were right, some people would take >that "clue" to consider that with 128 output frequencies available, >those pins would be for a serial data input, a clock, and a latch which >would select any one of the 128 output frequencies you said were >available. I said that three pins were "strappable" to set the frequency. Are you now going to open a debate about whether SPI programming is a special case of strapping? We're also using some tiny surface-mount VCXOs whose frequency *can* truly be programmed over a very wide range... to PPB resolution. John
From: John Fields on 18 Mar 2010 11:15 On Thu, 18 Mar 2010 07:39:42 -0700, John Larkin <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >On Thu, 18 Mar 2010 08:41:55 -0500, John Fields ><jfields(a)austininstruments.com> wrote: > >>On Wed, 17 Mar 2010 17:56:02 -0700, John Larkin >><jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >> >>>On Wed, 17 Mar 2010 16:37:47 -0500, John Fields >>><jfields(a)austininstruments.com> wrote: >>> >>>> >>>>>Yes, he and JT are unusually vulgar today. I figure they were cuddling >>>>>for warmth and the shawl fell off their knees. >>>> >>>>--- >>>>Geez, John, one of us finding you wrong and the other agreeing with that >>>>finding doesn't represent "cuddling" in my book, just statement of, and >>>>agreement on, objective fact. >>>> >>>>Of course being found wrong is "mea maxima culpa" when viewed through >>>>your deranged set of values and can't be allowed to coexist with what >>>>you hold precious; your infallibility, Mr. "Infinity only means >>>>something very large.", so you'll try to do whatever you can to fool all >>>>of the people all of the time even though all you do is fool yourself >>>>since you think you've gotten everyone to goose-step along with you. >>>> >>>>JF >>> >>> >>>Let's see, your brilliant corrections include >>> >>>Disputing whether unboundedly large things can be properly referred to >>>as "infinite" >> >>--- >>Even in the original context, where you claimed that switching relays >>exhibit infinite gain, they _cannot_ because the power used to switch >>them is non-zero. > >You must be another nym of AlwaysWrong. He's obscessed with how I use >a cleaning machine, and you're obscessed with how I once used the word >"infinite." --- "Guilt by association", huh? Tricky... Hardly "obscessed", I just like to use that little incident every now and then to point out that you have feet of clay and how far you'll go to try to deny that you don't. --- >>>and Correcting me when I said a divisor can be programmed from 1 to 128, >>>without specifying the programming step size. >> >>--- >>Well, in reality it was originally: >> >>"We're using one part that's pin strappable for 8-4-2-1 MHz." > >But it is strappable for those frequencies. --- And more, which you'd have included if you had a clue back then. --- >>Then, when you got called on that it changed to: >> >>"It's basically an 8 MHz oscillator with three pins that can be strapped >>to divide by 1 through 128." >> >>Now, I know you're from Louisiana, so English isn't your first language, >>but when most of the rest of us read: "1 through 128", we generally tend >>to include all of the counting numbers between 1 and 128. > >Not people who can figure out that 3 bits only have 8 states. --- Yeah, but 3 _pins_ can easily access many more, and your "1 through 128" mistakenly alluded to that, as I pointed out earlier in my last post. --- >And anybody who is picky about details can always read the datasheet. --- Which I gave you credit for finally coming up with a link to. --- >>Just for your future reference, if it's: "1 through 128, inclusive", >>that includes the numbers on the ends. > >And JT calls me prissy! --- Because you are! --- >>>I did say that three >>>pins did the selection, which some people would take as a clue. >> >>--- >>And, believing mistakenly that you were right, some people would take >>that "clue" to consider that with 128 output frequencies available, >>those pins would be for a serial data input, a clock, and a latch which >>would select any one of the 128 output frequencies you said were >>available. > >I said that three pins were "strappable" to set the frequency. Are you >now going to open a debate about whether SPI programming is a special >case of strapping? --- No, _you_ already did that by associating "1 through 128" with the 3 pins, whatever "strapping" means. --- >We're also using some tiny surface-mount VCXOs whose frequency *can* >truly be programmed over a very wide range... to PPB resolution. --- Sidestep, but... That's not really the same thing, is it? JF
From: John Larkin on 18 Mar 2010 12:01
On Thu, 18 Mar 2010 10:15:52 -0500, John Fields <jfields(a)austininstruments.com> wrote: >On Thu, 18 Mar 2010 07:39:42 -0700, John Larkin ><jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: > >>On Thu, 18 Mar 2010 08:41:55 -0500, John Fields >><jfields(a)austininstruments.com> wrote: >> >>>On Wed, 17 Mar 2010 17:56:02 -0700, John Larkin >>><jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >>> >>>>On Wed, 17 Mar 2010 16:37:47 -0500, John Fields >>>><jfields(a)austininstruments.com> wrote: >>>> >>>>> >>>>>>Yes, he and JT are unusually vulgar today. I figure they were cuddling >>>>>>for warmth and the shawl fell off their knees. >>>>> >>>>>--- >>>>>Geez, John, one of us finding you wrong and the other agreeing with that >>>>>finding doesn't represent "cuddling" in my book, just statement of, and >>>>>agreement on, objective fact. >>>>> >>>>>Of course being found wrong is "mea maxima culpa" when viewed through >>>>>your deranged set of values and can't be allowed to coexist with what >>>>>you hold precious; your infallibility, Mr. "Infinity only means >>>>>something very large.", so you'll try to do whatever you can to fool all >>>>>of the people all of the time even though all you do is fool yourself >>>>>since you think you've gotten everyone to goose-step along with you. >>>>> >>>>>JF >>>> >>>> >>>>Let's see, your brilliant corrections include >>>> >>>>Disputing whether unboundedly large things can be properly referred to >>>>as "infinite" >>> >>>--- >>>Even in the original context, where you claimed that switching relays >>>exhibit infinite gain, they _cannot_ because the power used to switch >>>them is non-zero. >> >>You must be another nym of AlwaysWrong. He's obscessed with how I use >>a cleaning machine, and you're obscessed with how I once used the word >>"infinite." >--- >"Guilt by association", huh? > >Tricky... > >Hardly "obscessed", I just like to use that little incident every now >and then to point out that you have feet of clay and how far you'll go >to try to deny that you don't. >--- > >>>>and Correcting me when I said a divisor can be programmed from 1 to 128, >>>>without specifying the programming step size. >>> >>>--- >>>Well, in reality it was originally: >>> >>>"We're using one part that's pin strappable for 8-4-2-1 MHz." >> >>But it is strappable for those frequencies. > >--- >And more, which you'd have included if you had a clue back then. >--- > Read my post. I said that I was at home, speaking from memory, and that I didn't recall the exact part number. Given that, I only said things that were true. When I got to work and looked it up, I did post the LTC part number, at which point anybody interested could look it up and get all the gory details. I never said anything about the part that wasn't true. >>>Then, when you got called on that it changed to: >>> >>>"It's basically an 8 MHz oscillator with three pins that can be strapped >>>to divide by 1 through 128." >>> >>>Now, I know you're from Louisiana, so English isn't your first language, >>>but when most of the rest of us read: "1 through 128", we generally tend >>>to include all of the counting numbers between 1 and 128. >> >>Not people who can figure out that 3 bits only have 8 states. > >--- >Yeah, but 3 _pins_ can easily access many more, and your "1 through 128" >mistakenly alluded to that, as I pointed out earlier in my last post. >--- > >>And anybody who is picky about details can always read the datasheet. > >--- >Which I gave you credit for finally coming up with a link to. >--- When I got to work and checked the part number, that's what I did. > >>>Just for your future reference, if it's: "1 through 128, inclusive", >>>that includes the numbers on the ends. >> >>And JT calls me prissy! > >--- >Because you are! >--- > >>>>I did say that three >>>>pins did the selection, which some people would take as a clue. >>> >>>--- >>>And, believing mistakenly that you were right, some people would take >>>that "clue" to consider that with 128 output frequencies available, >>>those pins would be for a serial data input, a clock, and a latch which >>>would select any one of the 128 output frequencies you said were >>>available. >> >>I said that three pins were "strappable" to set the frequency. Are you >>now going to open a debate about whether SPI programming is a special >>case of strapping? > >--- >No, _you_ already did that by associating "1 through 128" with the 3 >pins, whatever "strapping" means. You don't know what pin strapping means? >--- > >>We're also using some tiny surface-mount VCXOs whose frequency *can* >>truly be programmed over a very wide range... to PPB resolution. > >--- >Sidestep, but... > >That's not really the same thing, is it? The same thing as what? We were discussing oscillators, and new types of oscillators are an interesting offshoot. As you get older, you can settle into doing 555 circuits over and over, "the same thing", or you can keep up on new things that are possible. I think it's fun to talk about and design with new things. http://www.silabs.com/support/pages/support.aspx?ProductFamily=VCXOs A couple of other people make similar any-frequency XOs and VCXOs. Now you can run to the dictionary and start a debate about the meaning of "any." Enjoy. John |