Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> Wrote in message:> On 01/31/2016 04:43 PM, bitrex wrote: >> Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> Wrote in >> message: >>> On 01/31/2016 03:42 PM, bitrex wrote: >>> >>>>> >>>>> You've already said that you're a moral relativist, so there's >>>>> no use appealing to your better nature. ;) >>>> >>>> True, but it doesn't seem to stop people from trying... >>> >>> A lot of moral relativists are much better than their principles, >>> and I hope you're one. The principles themselves are so bad that >>> it's scarcely possible for someone to be worse. >>> >>> I try very hard to deal only with straight shooters. I've had to >>> fire customers who weren't, and I certainly wouldn't knowingly work >>> with someone whose moral ideas were controlled by his own >>> convenience. >>> >>> Cheers >>> >>> Phil Hobbs >>> >> >> The weird thing is, regardless of my moral relativism, I seem to >> generally behave in a moral fashion. But I couldn't tell you exactly >> why. Guess I had those messages drilled into me real good and I >> can't handle the cognitive dissonance. I catch spiders and gently put >> them outside. > > Which does make you better than your principles, at least part of the > time. You might want to inquire--as a matter of some urgency--where > that higher moral law (for that is what it is) that judges your > intentions comes from.A sociopathic rapist murder goes to Heaven because he accepts Christ on his deathbed, but an atheist who lived a moral life to the best of their abilities within the structure of their society is damned, because they didn't accept that someone died for their sins (of which they likely committed fairly few.) lol, want talk about universal concepts of "fairness"! -- ----Android NewsGroup Reader---- http://usenet.sinaapp.com/
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Started by ●January 31, 2016
Reply by ●January 31, 20162016-01-31
Reply by ●January 31, 20162016-01-31
On 01/02/16 10:00, Phil Hobbs wrote:> On 01/31/2016 04:43 PM, bitrex wrote: >> The weird thing is, regardless of my moral relativism, I seem to >> generally behave in a moral fashion > Which does make you better than your principlesWhat makes you the expert in someone else's moral principles? Sheesh, that arrogance surely knows no bounds.> One of the many problems with that view is the immense agreement between > people of all eras and all places on what is and is not OK.So therefore there's something extra-physical, mystical, magical, non-material, from which all moral truth descends? That's a total failure of logic. Could it be that folk just recognize that they need to try to contribute to making and maintaining the kind of world they'd like to live in? That they have a responsibility - even a selfish one - to maintain a moral order? C'mon, it's not that hard to imagine! No need to invent angels and faeries to define the truth for us, and then try to use logic to prove they're not invented. Hilarious. Clifford Heath.
Reply by ●January 31, 20162016-01-31
On Sun, 31 Jan 2016 18:24:55 -0500 (EST), bitrex <bitrex@de.lete.earthlink.net> wrote:>Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> Wrote in message: >> On 01/31/2016 04:43 PM, bitrex wrote: >>> Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> Wrote in >>> message: >>>> On 01/31/2016 03:42 PM, bitrex wrote: >>>> >>>>>> >>>>>> You've already said that you're a moral relativist, so there's >>>>>> no use appealing to your better nature. ;) >>>>> >>>>> True, but it doesn't seem to stop people from trying... >>>> >>>> A lot of moral relativists are much better than their principles, >>>> and I hope you're one. The principles themselves are so bad that >>>> it's scarcely possible for someone to be worse. >>>> >>>> I try very hard to deal only with straight shooters. I've had to >>>> fire customers who weren't, and I certainly wouldn't knowingly work >>>> with someone whose moral ideas were controlled by his own >>>> convenience. >>>> >>>> Cheers >>>> >>>> Phil Hobbs >>>> >>> >>> The weird thing is, regardless of my moral relativism, I seem to >>> generally behave in a moral fashion. But I couldn't tell you exactly >>> why. Guess I had those messages drilled into me real good and I >>> can't handle the cognitive dissonance. I catch spiders and gently put >>> them outside. >> >> Which does make you better than your principles, at least part of the >> time. You might want to inquire--as a matter of some urgency--where >> that higher moral law (for that is what it is) that judges your >> intentions comes from. >> >>> >>> But given some of the horrible experiences I've had in life, I find >>> it very difficult to believe that morality is anything innate or >>> universal. At the end of the day, the Universe doesn't care. >> >> One of the many problems with that view is the immense agreement between >> people of all eras and all places on what is and is not OK. There are >> disagreements at the edges, e.g. whether you have to be unselfish >> towards everybody or just your own family/tribe/clan/nation, or whether >> you can have one wife or five. >> >> But I claim that you can't actually imagine a society that sincerely >> admired people who ran away in battle, or who double-crossed all their >> friends, for instance. >> > >Well, yeah, a society made completely of atavistic sociopaths > wouldn't last very long. But then that means at some level > morality is something that must evolve parallel to humans living > in societies at all, which means it must stem from a particular > society. i.e. it's not a universal innate quality of humans. > > >Maybe it might be better to say that certain humans have an innate > _capability_ for morality, in the same sense that every human > born with certain physical and mental characteristics has the > capability to be an astronaut, given the right environment and > the right life circumstances. > >I'm pretty sure that some people (fortunately a small amount) are > born rotten. They come that way from the factory and nothing can > change it. I definitely don't belive in any innate "goodness" of > humans, or that we're all made in God's image.It's advantageous for an individual to live in a society of honest and productive and generous people, and it's advantageous for that person to steal all he can. So, we have laws. -- John Larkin Highland Technology, Inc lunatic fringe electronics
Reply by ●January 31, 20162016-01-31
John Larkin <jjlarkin@highlandtechnology.com> Wrote in message:> On Sun, 31 Jan 2016 18:24:55 -0500 (EST), bitrex > <bitrex@de.lete.earthlink.net> wrote: > >>Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> Wrote in message: >>> On 01/31/2016 04:43 PM, bitrex wrote: >>>> Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> Wrote in >>>> message: >>>>> On 01/31/2016 03:42 PM, bitrex wrote: >>>>> >>>>>>> >>>>>>> You've already said that you're a moral relativist, so there's >>>>>>> no use appealing to your better nature. ;) >>>>>> >>>>>> True, but it doesn't seem to stop people from trying... >>>>> >>>>> A lot of moral relativists are much better than their principles, >>>>> and I hope you're one. The principles themselves are so bad that >>>>> it's scarcely possible for someone to be worse. >>>>> >>>>> I try very hard to deal only with straight shooters. I've had to >>>>> fire customers who weren't, and I certainly wouldn't knowingly work >>>>> with someone whose moral ideas were controlled by his own >>>>> convenience. >>>>> >>>>> Cheers >>>>> >>>>> Phil Hobbs >>>>> >>>> >>>> The weird thing is, regardless of my moral relativism, I seem to >>>> generally behave in a moral fashion. But I couldn't tell you exactly >>>> why. Guess I had those messages drilled into me real good and I >>>> can't handle the cognitive dissonance. I catch spiders and gently put >>>> them outside. >>> >>> Which does make you better than your principles, at least part of the >>> time. You might want to inquire--as a matter of some urgency--where >>> that higher moral law (for that is what it is) that judges your >>> intentions comes from. >>> >>>> >>>> But given some of the horrible experiences I've had in life, I find >>>> it very difficult to believe that morality is anything innate or >>>> universal. At the end of the day, the Universe doesn't care. >>> >>> One of the many problems with that view is the immense agreement between >>> people of all eras and all places on what is and is not OK. There are >>> disagreements at the edges, e.g. whether you have to be unselfish >>> towards everybody or just your own family/tribe/clan/nation, or whether >>> you can have one wife or five. >>> >>> But I claim that you can't actually imagine a society that sincerely >>> admired people who ran away in battle, or who double-crossed all their >>> friends, for instance. >>> >> >>Well, yeah, a society made completely of atavistic sociopaths >> wouldn't last very long. But then that means at some level >> morality is something that must evolve parallel to humans living >> in societies at all, which means it must stem from a particular >> society. i.e. it's not a universal innate quality of humans. >> >> >>Maybe it might be better to say that certain humans have an innate >> _capability_ for morality, in the same sense that every human >> born with certain physical and mental characteristics has the >> capability to be an astronaut, given the right environment and >> the right life circumstances. >> >>I'm pretty sure that some people (fortunately a small amount) are >> born rotten. They come that way from the factory and nothing can >> change it. I definitely don't belive in any innate "goodness" of >> humans, or that we're all made in God's image. > > It's advantageous for an individual to live in a society of honest and > productive and generous people, and it's advantageous for that person > to steal all he can. So, we have laws. >Yep, but any society of sufficient size can always stably support a few chronic vampires that will be successful pulling it off. -- ----Android NewsGroup Reader---- http://usenet.sinaapp.com/
Reply by ●January 31, 20162016-01-31
On Sun, 31 Jan 2016 17:52:24 -0500, mixed nuts <melopsitticus@undulatus.budgie> wrote:>On 1/31/2016 4:31 PM, John Larkin wrote: >> On Sun, 31 Jan 2016 14:58:48 -0500, mixed nuts >> <melopsitticus@undulatus.budgie> wrote: >>> On 1/31/2016 12:26 PM, bitrex wrote: >>>> John Larkin <jjlarkin@highlandtechnology.com> Wrote in message: >>>>> On Sun, 31 Jan 2016 05:34:23 -0600, "Tim Williams" >>>>> <tiwill@seventransistorlabs.com> wrote: >>>>> >>>>>> Designing an RF amplifier. Concept is, high power, complementary cascodes >>>>>> for the output stage (with heavy class A use, but being PP, class AB is an >>>>>> option). 50 ohm output, direct drive, say 10W level. >>>>>> >>>>>> I happen to have a complementary pair that's not too slow (2SC2690A and >>>>>> 2SA1220A), and I'd like to maximize the bandwidth around that. The NPN >>>>>> side is fine, I have a 30V, 1A, 2GHz transistor that would pair very well >>>>>> with it. Don't have any such thing for the PNP side. >>>>>> >>>>>> So, what if I fake a PNP, by wrapping, say, a BFT92 around the NPN? >>>>>> http://seventransistorlabs.com/Images/Sziklai_Cascode.png >>>>>> That'd be Q1 = BFT92, Q2 = 2SC4821, Q3 = 2SA1220A, and resistors for >>>>>> flavor, but probably roughly representative. (Ground wouldn't actually be >>>>>> ground-ground, but probably something like +40V, and "+12V" would be >>>>>> +45V.) >>>>>> >>>>>> The combination is still fast... ah, but Sziklai connections have a >>>>>> propensity for oscillation all their own, let alone in a cascode, plus >>>>>> whatever other machinations I might have for feedback around the thing. >>>>>> Game killer? >>>>>> >>>>>> The other option would be folded cascode, which is understandably rather >>>>>> wasteful for a power stage! >>>>>> >>>>>> Tim >>>>> >>>>> What's the frequency and the bandwidth requirement? >>>>> >>>>> Regular low-frequency circuit topologies generally don't scale well >>>>> into RF amps. >>>>> >>>> >>>> Does anyone use that admittance/Z parameter matrix stuff for RF >>>> amp design/stability analysis that I've read about in books like >>>> "Intro to RF Design" by Wes Hayward, or do they just mess with it >>>> in Spice and are then like "eh works well enough ship >>>> it" >>> >>> Not so much anymore - it's all wired into RF design packages - some >>> bloody expensive, a couple free. SPICE input files can be used - if you >>> have a well characterized SPICE model, the simulation engine will >>> understand it. S-Parameter simulations are the norm. Generally, these >>> packages will work with MATLAB/Octave, VHDL, Verilog... or have >>> something similar built in - lots of post processing and modeling options. >>> >>> SPICE sucks for modeling transmission lines. The RF/Microwave packages >>> will work directly with dimensions and materials - just plug in the >>> numbers or click on a library definition. Life is good. >> >> Think so? I Spice txlines all the time, and the results seem to be >> realistic. > >It can be done - and I did it when there were no other options with >realistic results. The problem comes, for example, when you're dealing >with a dispersive structure over a wide bandwidth with frequency >dependent losses. With SPICE you have to generate a lumped element >equivalent circuit which may consist of 20 sections (to get good numbers >over 4 octaves). Each section is a 3 element LP but the L is a set of >inductors and resistors to produce a piecewise approximation to skin >effect (fractional pole expansion - see >http://www.designers-guide.org/Modeling/ind.pdf ). > >Farkin' tedious, especially when you have 2 balanced lines broken up >into 6 subsections that you want to vary length to tune to one >frequency, null another, and couple a signal in/out. > >So, being able to drop the pieces onto a schematic, plug in dielectric >constants, physical dimensions and conductivities, select a well tested >model for the dispersive component and go is much nicer. > >This is an xml definition for a one section of a coupled microstrip filter: > > <MCOUPLED MS1 1 410 840 -26 37 0 0 "Subst1" 1 "384um" 1 "5.24mm" 1 >"482um" 1 "Kirschning" 0 "Kirschning" 0 "26.85" 0> > >"Subst1" further expands in a piece of 30 mil thick Rogers Duroid 5880. >"Kirschning" is a recognized model for dispersive microstrip. The >numbers are entered into a dialog box or pulled in from a library. > >Less pain.LT Spice has the ltline element, a classic Heaviside lossy transmission line. It doesn't do higher-order things like skin effect. At some point, prototype it or get some big-bucks EM modeling software. -- John Larkin Highland Technology, Inc lunatic fringe electronics
Reply by ●January 31, 20162016-01-31
On 01/31/2016 06:24 PM, bitrex wrote:> Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> Wrote in > message: >> On 01/31/2016 04:43 PM, bitrex wrote: >>> Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> Wrote in >>> message: >>>> On 01/31/2016 03:42 PM, bitrex wrote: >>>> >>>>>> >>>>>> You've already said that you're a moral relativist, so >>>>>> there's no use appealing to your better nature. ;) >>>>> >>>>> True, but it doesn't seem to stop people from trying... >>>> >>>> A lot of moral relativists are much better than their >>>> principles, and I hope you're one. The principles themselves >>>> are so bad that it's scarcely possible for someone to be >>>> worse. >>>> >>>> I try very hard to deal only with straight shooters. I've had >>>> to fire customers who weren't, and I certainly wouldn't >>>> knowingly work with someone whose moral ideas were controlled >>>> by his own convenience. >>>> >>>> Cheers >>>> >>>> Phil Hobbs >>>> >>> >>> The weird thing is, regardless of my moral relativism, I seem to >>> generally behave in a moral fashion. But I couldn't tell you >>> exactly why. Guess I had those messages drilled into me real good >>> and I can't handle the cognitive dissonance. I catch spiders and >>> gently put them outside. >> >> Which does make you better than your principles, at least part of >> the time. You might want to inquire--as a matter of some >> urgency--where that higher moral law (for that is what it is) that >> judges your intentions comes from. >> >>> >>> But given some of the horrible experiences I've had in life, I >>> find it very difficult to believe that morality is anything >>> innate or universal. At the end of the day, the Universe doesn't >>> care. >> >> One of the many problems with that view is the immense agreement >> between people of all eras and all places on what is and is not OK. >> There are disagreements at the edges, e.g. whether you have to be >> unselfish towards everybody or just your own >> family/tribe/clan/nation, or whether you can have one wife or >> five. >> >> But I claim that you can't actually imagine a society that >> sincerely admired people who ran away in battle, or who >> double-crossed all their friends, for instance. >> > > Well, yeah, a society made completely of atavistic sociopaths > wouldn't last very long.I'm not talking about that, I'm talking about the difference between "ought to be" and "is".> But then that means at some level morality is something that must > evolve parallel to humans living in societies at all, which means it > must stem from a particular society. i.e. it's not a universal innate > quality of humans.But that's contrary to the evidence. You're a victim of your preconceptions here.> > > Maybe it might be better to say that certain humans have an innate > _capability_ for morality, in the same sense that every human born > with certain physical and mental characteristics has the capability > to be an astronaut, given the right environment and the right life > circumstances.Again, morality is about "ought to", not "is".> > I'm pretty sure that some people (fortunately a small amount) are > born rotten. They come that way from the factory and nothing can > change it. I definitely don't belive in any innate "goodness" of > humans, or that we're all made in God's image.But how do you define "rotten", if there's no standard? How can you say that a saint or a great humanitarian is "better" than a Mafia don or a drug dealer, if there's no standard? Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 hobbs at electrooptical dot net http://electrooptical.net
Reply by ●January 31, 20162016-01-31
On 01/31/2016 06:31 PM, bitrex wrote:> Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> Wrote in message: >> On 01/31/2016 04:43 PM, bitrex wrote: >>> Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> Wrote in >>> message: >>>> On 01/31/2016 03:42 PM, bitrex wrote: >>>> >>>>>> >>>>>> You've already said that you're a moral relativist, so there's >>>>>> no use appealing to your better nature. ;) >>>>> >>>>> True, but it doesn't seem to stop people from trying... >>>> >>>> A lot of moral relativists are much better than their principles, >>>> and I hope you're one. The principles themselves are so bad that >>>> it's scarcely possible for someone to be worse. >>>> >>>> I try very hard to deal only with straight shooters. I've had to >>>> fire customers who weren't, and I certainly wouldn't knowingly work >>>> with someone whose moral ideas were controlled by his own >>>> convenience. >>>> >>>> Cheers >>>> >>>> Phil Hobbs >>>> >>> >>> The weird thing is, regardless of my moral relativism, I seem to >>> generally behave in a moral fashion. But I couldn't tell you exactly >>> why. Guess I had those messages drilled into me real good and I >>> can't handle the cognitive dissonance. I catch spiders and gently put >>> them outside. >> >> Which does make you better than your principles, at least part of the >> time. You might want to inquire--as a matter of some urgency--where >> that higher moral law (for that is what it is) that judges your >> intentions comes from. >> > > A higher moral law giving humans free will, but then essentially > revoking it in the same breath by dictating that there will be > horrible consequences for not using it in the appropriate > fashion, and then giving the players no option whether the wish > to play or not (being born) seems like a rather perverse game.I don't know anybody who advances such a worldview. Do you?> You might sometimes question the sanity of whatever moral > authority wants to run that one.If there were such a person, I certainly would. But there isn't, as far as I know.> > But yeah, I'm pretty sure that if there was a Son of God, Christ > was a good candidate. Tell people to love each other, get nailed > to a cross? Sure. Sounds like just the sort of thing people would > do.Absolutely. But He also exhibited what love looked like in an altogether unique way. Hint: it isn't always about making nice. If your teenage daughter is a heroin addict, you don't say, "That's lovely, dear, have a good time shooting up in the back alley." Sin is like that--harmful from the beginning, and in the end, lethal. Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 hobbs at electrooptical dot net http://electrooptical.net
Reply by ●January 31, 20162016-01-31
On 01/31/2016 06:39 PM, bitrex wrote:> Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> Wrote in message: >> On 01/31/2016 04:43 PM, bitrex wrote: >>> Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> Wrote in >>> message: >>>> On 01/31/2016 03:42 PM, bitrex wrote: >>>> >>>>>> >>>>>> You've already said that you're a moral relativist, so there's >>>>>> no use appealing to your better nature. ;) >>>>> >>>>> True, but it doesn't seem to stop people from trying... >>>> >>>> A lot of moral relativists are much better than their principles, >>>> and I hope you're one. The principles themselves are so bad that >>>> it's scarcely possible for someone to be worse. >>>> >>>> I try very hard to deal only with straight shooters. I've had to >>>> fire customers who weren't, and I certainly wouldn't knowingly work >>>> with someone whose moral ideas were controlled by his own >>>> convenience. >>>> >>>> Cheers >>>> >>>> Phil Hobbs >>>> >>> >>> The weird thing is, regardless of my moral relativism, I seem to >>> generally behave in a moral fashion. But I couldn't tell you exactly >>> why. Guess I had those messages drilled into me real good and I >>> can't handle the cognitive dissonance. I catch spiders and gently put >>> them outside. >> >> Which does make you better than your principles, at least part of the >> time. You might want to inquire--as a matter of some urgency--where >> that higher moral law (for that is what it is) that judges your >> intentions comes from. > > A sociopathic rapist murder goes to Heaven because he accepts > Christ on his deathbed, but an atheist who lived a moral life to > the best of their abilities within the structure of their society > is damned, because they didn't accept that someone died for their > sins (of which they likely committed fairly few.)Where do you get the idea that any of us is permitted to speculate on the eternal fate of another? Christ Himself explicitly forbade it. That's what "Judge not, lest ye be judged" means. It isn't about behaviour--we're expected to be sensible about _that_--but we can't possibly set bounds to the mercy of God.> > lol, want talk about universal concepts of "fairness"!Again, I don't know anybody who advances the view you recite. Do you? Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 hobbs at electrooptical dot net http://electrooptical.net
Reply by ●January 31, 20162016-01-31
"John Larkin" wrote in message news:ecvsab1s93c4v3joh7imn68pb5ngthqg6k@4ax.com...>The real fork in the road is whether it needs to be wideband. A 100 >MHz amp is a lot different from a DC-to-100 MHz amp. Narrowband, you >can tune out parasitics, which is how people get tubes and mosfets to >work at a GHz. > >Wideband gets more interesting. > >What's it for?Well, including DC basically means replacing inductors with complementary PP, or CCSs. And bandwidth is just the span from "near DC" to whatever the HF cutoff is. You can tweak a "narrow" amp into a "wide" one by playing with the filter topology and impedances. Suppose you start with a conventional narrowband amplifier, using parallel tuned resonators, and matched with whatever means apply (L-match, L or C dividers, tapped coils..). At each resonator, the ratio of resonator Zo to system Z gives the Q factor and therefore width of that stage (give or take stacking resonators for flatter bandpass, sharper skirts, and slightly stretching (peaking) the bandwidth limits). As you reduce Q (assuming you are able to, by increasing Z and L, and reducing C; normally C has a minimum due to the amplifying device, which trades off with Z as an approximate GBW limitation), the bandwidth spreads out, and the impedance ratios available via reactive matching networks get closer to 1. So you start needing more transformers than reactive networks for matching, and resonators with impedances closer to the device or system impedance. Which tend to get less extreme and therefore easier to construct. Series-parallel transformations can be reversed, giving traditional filter topologies, like series resonant links between parallel resonant tanks, instead of coupled resonators. As BW rises still further, Q < 1 means R dominates over X for much of the band, and the networks aren't really resonators at all anymore, so you can pull them apart, using large value RFCs to supply bias, and using LPF network design to manage the device capacitance. At this point, it's usually relatively trivial to convert the remaining RFCs and coupling capacitors into DC-friendly R or CCS parts, at the usual cost of efficiency. Transformers being the one exception, for which you need to change much more (supply voltages, transistor types..). (This being one of the fundamental limitations of vacuum tubes -- high load impedance.) So along this spectrum, I expect to design an amplifier in one of the latter categories: treating HP and LP behavior separately, using matching if necessary. "Wideband" means different things to different people. I've seen planar circuits claiming 1GHz "wideband" performance. Sure, that's pretty wide in the usual scheme of things, but out of a 20GHz center frequency, that's a puny 5%... a Q of 20... To me, I mean a circuit where the LP and HP behavior is roughly independent, and the HP is optional (so that it may truly include DC). Speaking of tubes -- they work just fine at high frequencies. 6C4 is a rather unimpressive type, but an oscillator built with one (running at a modest, say, 100MHz) will show harmonics out to nearly 1GHz! It's the only nonlinear element in the circuit, so all those harmonics are indeed due to changes in electron flow occurring that fast. Of course, those harmonics are in the -80dB range, so it's not like there's much left up there. (It's also relatively unusable, because electrode self-resonances occur in the 300MHz+ range.) But the physics is real. Planar triodes of course went out to about 10GHz, and TWTs are still around with us today. I don't think most transistors drop off in the same way. Tubes have such low current density (and therefore high Z and low Gm) that, for baseband, electrode capacitance dominates over the fundamental limitations. Most BJTs have R_L* Ccb dropping off around the same range as fT (which is due to Rb * Cbe and diffusion/recombination). I suspect that power switching FETs are similarly Ciss * Rg limited; but RF FETs (in Si) have quite high limitations (small Cin and Cout, low Rg), when made properly. There was one RF part that you found rather lazy, an HBT I think? That's probably such an example. Relatively high Cout, but fT through the roof? Coming from your main perspective, I think -- most of your projects have been limited to baseband, and thus your HF limit is pretty much 1 / (2*pi*Cout*R_L). With peaking, a little over double this, but I'm guessing for your applications, dropping in a superlative GaNFET or whatever is more efficacious and economical. And if this were a job job, I'd do the same, but fortunately it's not, so I can take the learning opportunity instead. :-) Application, just lab use, maybe a little radio when I get there (hey, just add a wideband antenna and you're set, no need for "tuning the finals" :) ). Tim -- Seven Transistor Labs, LLC Electrical Engineering Consultation and Contract Design Website: http://seventransistorlabs.com
Reply by ●January 31, 20162016-01-31
On 01/31/2016 06:45 PM, Clifford Heath wrote:> On 01/02/16 10:00, Phil Hobbs wrote: >> On 01/31/2016 04:43 PM, bitrex wrote: >>> The weird thing is, regardless of my moral relativism, I seem to >>> generally behave in a moral fashion >> Which does make you better than your principles > > What makes you the expert in someone else's moral principles? > Sheesh, that arrogance surely knows no bounds.Sorry? It's okay with you if I rob you blind because I think it's okay?>> One of the many problems with that view is the immense agreement between >> people of all eras and all places on what is and is not OK. > > So therefore there's something extra-physical, mystical, magical, > non-material, from which all moral truth descends? That's a total > failure of logic.I didn't say that. You keep going on about mystical magical stuff, whereas I'm talking about the basic structure of existence.> > Could it be that folk just recognize that they need to try to contribute > to making and maintaining the kind of world they'd like to live in? That > they have a responsibility - even a selfish one - to maintain a moral > order?No, it couldn't. Otherwise nobody would do the right thing when nobody was looking. Some people do.> > C'mon, it's not that hard to imagine! No need to invent angels and > faeries to define the truth for us, and then try to use logic to prove > they're not invented. Hilarious.If anyone actually thought that, it might be. But you're just whistling in the dark. Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 hobbs at electrooptical dot net http://electrooptical.net
