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Everything posted by @~thehung

  1. @~thehung

    Smallest, most direction antenna

    ohhh righhhhht ... i think i see the cause of misunderstanding now. that car analogy OMG WTF! :P well i cant blame you since i never stated it all explicitly in one chunk. - the antennas are monopole omnis. - when i originally said "rotate the orientation of the two antennas while mapping the spectra of their summed signal for all compass directions" i was talking about rotating the array — ie. two antennas both affixed to a single rigid structure at around 1/2λ apart — so that a measurement is made at 'every' bearing represented by a straight line between antenna A and antenna B. so for example, ignoring coupling, if the transmitter was due north, you would expect near cancellation when the array is pointed at either 0° or 180°. yes?
  2. @~thehung

    Smallest, most direction antenna

    LOL nice one. so maybe you know little beyond generalities then? because youve had ample opportunity to add something pertinent. if you check the relevant section of the technical paper i quoted from there is actually a graph showing the amount of mutual impedance due to coupling as a function of antenna separation in fractions of a wavelength. yeah, somehow that hadnt escaped my attention, and has never been in dispute. just so we are clear, i was supposing that the distance between the rotated antennas would remain constant. IF it is your contention that no useful phase information (ie. ZERO) could possibly survive the presence of ANY amount of coupling (Z > 0), then why not educate me on how and why this is the case? shouldnt be too hard if you actually know what you are talking about and are actually interested in a civil discussion.
  3. @~thehung

    Smallest, most direction antenna

    perhaps i should have said "...incidence of incoming signal direction of arrival" instead. i wasnt talking about the orientation or type of transmitter. "Note that in general, the definition of the receiving mutual impedance implies that the receiving mutual impedance is dependent on the direction of the plane wave, which is used as the excitation source. But for omni-directional antennas such as dipole and monopole antennas, the receiving mutual impedance is independent of the azimuth angle of the excitation plane wave." https://studylib.net/doc/18215614/mutual-coupling-in-antenna-arrays still not convinced you grasp what i am proposing about the symmetry of the spectral information. do you have anything more elucidating to add than 'it will fuck your shit up'?
  4. @~thehung

    Smallest, most direction antenna

    maybe you missed my point. i understand well enough what it is in general terms. and after some reading i am under the impression that the mutual coupling effect on two receiving monopoles is independent of transmitter direction. it will surely play havoc on SNR regardless of what exactly it does to phase/magnitude, so there is that — but my point was there will still likely be symmetry either side of the bearing to the transmitter (pointing towards or away). if you expect otherwise for some specific reason, then do elaborate. i can see that accounting for the errors added to any two omnis rooted to the ground would result in calculating a useless range of maybes, but propose that when data from all orientations is mapped, a true bearing could be inferred.
  5. @~thehung

    What Did You Watch Lately ?

    knew nothing of them, so watched a couple mins, switched tabs while it played, all the while thinking this Greta chick is a little too butch to find attractive but damn if she doesnt have an impressive androgenous power to her vocals HAHAHAHA really fricken good. the Plant flavour is super strong obviously, especially in the way its produced, but somehow his vocals dont feel like lame-assed mimicry either. theres flavours of other notables in there too, but most importantly, his sound is 'authentic' in its own right. cant say i have been yearning for a zeppelin-esque aesthetic for a long while, but if this song is representative of the band i will be looking to them if/when the mood hits, looooong before the likes of *spit* shitemother.
  6. @~thehung

    Smallest, most direction antenna

    yes it seems like that could be somewhere between significant and deal breaker as far as i can tell 'mutual coupling' is expressed as an impedance but its unclear to me how this effects magnitude/phase and hence adds ambiguity however - what i proposed above *might* diminish its relevance. suppose you can to rotate the orientation of the two antennas while mapping the spectra of their summed signal for all compass directions. even with a fairly FUBAR signal you should be able to identify some kind of pattern of symmetry either side of the points where total cancellation would (ideally) be expected. and drastically more precisely than you could vs merely watching a meter.
  7. @~thehung

    What Did You Watch Lately ?

    shame about the post fight mayhem, but the beating McGregor was taking during the second round was good to see after the bus incident.
  8. @~thehung

    Beth vs Nathaniel.

    yes and no. making certain presumptions about what "artistry" is, and what 'adding to it' means... yes, in that any substance capable of altering states of consciousness can add to someone's artistry. as for heroin, people who are pain free and in a relaxed and pleasant mood will find it easier and be more inclined to use their creative imagination. its reasonable to guess that in a one-off experiment in which 1000 randoms were tasked with being 'artistic', a carefully calibrated dose of heroin given to one half would result in them as a group producing art of superior quality/quantity by some objective measure. but then its also reasonable to assume that if the experiment were extended over a year with the participants given free reign to determine their dosage, the initial results would be resoundingly overturned. compared to many other drugs, opiates are inferior in their ability to enhance creativity at any time, and superior in their ability to bring disaster over time. so, no.
  9. @~thehung

    What's on your mind?

    look, i know theres inherent difficulties in that it isnt really possible to project the colour black, however, for the potential revenue its totally worth finding a way to make this work!
  10. @~thehung

    i see dead people

    https://www.dropbox.com/s/pt92rz4mxah0dil/ninjaisshakuhassun.mp3?dl=1 awesome!
  11. @~thehung

    And What Are You Listening To?

    ^that was great. makes reliving this for the umpteenth time obligatory. Vai vs Cooder. everything about this scene...cinematically...musically...PERFECT!
  12. @~thehung

    Cyberpunk 2077 - 48 minutes preview!

    interview with CD Projekt https://www.eurogamer.net/articles/2018-06-13-we-watched-50-minutes-of-uncut-cyberpunk-2077-gameplay-and-interviewed-cd-projekt-about-it
  13. i agree with all of that in principle Chaos, but it all depends on how you would actually apply it. something like this is usually intended in almost every unit on anything ever, but unfortunately in practice is so often reduced to superficial mind-numbing formality. anyone who has learnt about computers has covered Charles Babbage. but theres a world of difference between paying lip-service to the stale facts of history and, say, actually learning how the difference engine actually worked, and maybe even emulating some aspect of it with leggo mindstorms or something like that. so, yeah, as long as its done right.
  14. @~thehung

    Smallest, most direction antenna

    ha yeah TANSTAAFL now i am curious about what you would see if you just had 2 antennas 1/2λ apart, and then you summed them and eyeballed a spectogram. complex data and noise, but maybe you could identify a signature visual pattern — which is what our brains are good at — in the form of comb filtering either side of the bearing that you could keep sweeping past and hone in on.
  15. i think youre carrying on a conversation with yourself here. lots of non-sequiturs... you say this: "Again, I'm no pedagogy expert, but it seems to me that a syllabus should avoid including topics for reasons that (a) the creator thinks its interesting, or (b) its relevant to the creator." having just ignored this: "as for pedagogy, i dont presume that anything incorporating wired is necessarily "boring" compared to wifi or cant be of comparable educational value. it all depends, and its not like its a binary choice. " which pretty is pretty much a preemptive response. and you "strongly disagree that the history of IT is necessarily important" okaaaay? so are you just spitballing statements now because...non-sequiturs...or in your imagination i said that it is?
  16. first principles are so often neglected in education and it has always bothered me. too many jaded teachers obsessed with drilling empty facts so they can tick off another box on whatever flawed syllabus theyre stuck with. take pi for example. you might learn only how to apply it in an automatic way. but it doesnt take very long to manually derive in the way that Pythagoras did. not just glossing over the foundations has lasting benefits conceptually — if its done with active thinking, not just rote digestion of facts. sometimes slow and steady wins the race. i learnt more about the how and why of Newton's gravity law in Feynman's 1 hour lecture on it than in all of high school physics because he actually went back to first principles.
  17. token ring? well now you nerds are just going too far! :) if its there at all, it should be a one mark question in a quiz at the end of week 1 Which one of these is an example of ring topology? a) token protocol b) token ring c) onion router d) onion ring
  18. there was nothing in my post you needed to refute. i didnt take any strong position. nevertheless, you didnt quote the most salient point: when deciding on the relevance or lack thereof of wired to foundational knowledge, areas in which it still has longevity should not be forgotten. all very on topic re: "networking systems" as for pedagogy, i dont presume that anything incorporating wired is necessarily "boring" compared to wifi or cant be of comparable educational value. it all depends, and its not like its a binary choice.
  19. @~thehung

    Smallest, most direction antenna

    i didnt mean triangulation quite so literally. i meant, for any configuration of at least 3 antennas with a triangular relationship, you could think of the total +/- timing error* as positional error in terms of something like a radius around the idealised positions of each antenna. the actual measured 'triangle' represented by the phase data has to conform to points within those three circles. the maximum error between each pair of measurements is always constrained by the third, if they are to collectively be consistent with a known signal coming from a singular physical source. so, there could *potentially* be a probabalistic 'line of best fit triangle' drawn to apply fuzzy weighted corrections to the measurements. <-- already stupidly complicated in 2D. probably impossible in 3D. *lets just blithely assume that random mechanical error is known to make up the highest proportion.
  20. re: wireless vs wired it is now the done thing to learn to drive exclusively in an automatic car, although knowledge of manual is still good to have. we are approaching a similar point with wireless vs wired networking. its worth remembering though, that wired "PoE networks can power and control: Desktops, Access points, LED lighting, Monitoring systems, Surveillance cameras, VoIP phone systems, VDSL and DSLAM installations" https://www.versatek.com/blog/2018-update-ethernet-cabling-still-better-wifi/ @Kothos, that 2003 syllabus cannot still be active. i REFUSE to believe it.
  21. can be useful for a tenet who is configuring a residential router
  22. @~thehung

    Smallest, most direction antenna

    woah, hadnt even thought about 1. i assume that is like the reverse of a VOR beacon for aircraft navigation — which has a ring of transmitters that take turns, effectively applying FM to a carrier. makes me wonder about how fast the switching would need to be and the analogue side of that. as for the DSP of 2, i guess i am supposing that correlation would provide ample latitude for noisy/weak and time-smeared signals (mechanical or digital judder) and some of the timing error being reigned through deduction based on triangulation, but then again, they are probably too close together and i am imagining the receivers magically sitting on the same 2D plane as the transmitter.
  23. @~thehung

    Smallest, most direction antenna

    ok stadl tell me everything wrong with this harebrained idea :P 3 monopole antennas at the vertices of an equilateral triangle with a height at least, say, 1/8 λ a bearing is arrived at when two antennas show the same positive (near 90°) phase delay
  24. @~thehung

    Bullying: The risk with 'accepting differences'.

    i am inclined to characterise it as harassment and assault with extenuating circumstances rather than bullying. but whatever you call it, its still lizard-brained parental vigilantism that doesnt fly as the right thing to do™, at least not in 2018. its true that "it takes a village" doesnt mean what it used to. back when my dad was a juvenile, a kid getting a swift kick up the arse from a shop owner for low-level vandalism was all well and good. in some ways we've thrown the baby out with the bathwater. same goes for corporal punishment in schools: some kids would turn out better if it was still a thing. but, on balance, many more are better off without it. that age has passed. if your kid is victimised and you have no faith in the school system, then the first order of business is taking reasonable steps to address the issue verbally with a parent / legal guardian of the minor in question, with physically assaulting said minor being so far down the list as to not even be on the table. yes, in the real world 'aresholes that cant be reasoned with' are a multi-generational fact, and i do not assume the current orthodoxy has satisfactory solutions in place for every circumstance. but violence, especially against a kid must be assumed to be a last resort. personally, if i ever found myself convinced that a physical altercation with a parent was inevitable/necessary, i think i would be angling to have that occur in the principal's office