troly@CS.UCLA.EDU (12/15/87)
The net.debate on platygaeanism seems to have 3 sides. Platygeanism, rational round-earthism, and irrational hysterical round-earthism. I propose to get rid of this last group by flaming them out. Consider a posting by Ronald Cole. I wrote >>MATHEMATICAL CONSISTENCY DOES NOT IMPLY TRUTH. He replied >Then what does it imply? Can this be serious? He further wrote >Can you explain why matter has a nasty tendency to assume a spherical shape >when in free fall? Did a flat raindrop hit you on your flat head? !?!?!?!? This is really strange. Is he saying that the earth is round for the same reason that water droplet is rounded? (Actually a falling raindrop has a long attenuated tail due to air resistance.) That surface tension forces the earth into a round shape? Or that water droplets exemplify the "natural roundness" of nature, the bane of weight-watchers everywhere? :-) :-) You should be sure you understand both the theories you are attacking and those that you support before posting articles to the net. Evidently Ronald Cole understands neither. (Cheer up, Ronald, ignorance can be cured! :-) ) Numerous flames have been posted to the net about supposed conspiracy theories involving Communists, Secular Humanists (whatever they are), the CIA, the Bermuda triangle, The US army, Yetis, LSD experiments, Steven Spielberg(!), the AMA, the "sexist/war-mongering elite",... (I'm sure the Illuminati and the Vogons will pop up tomorrow :-) ). Gosh, platygaeanism sure looks kooky with all those paranoid theories, doesn't it. But has anyone noticed that all those theories have nothing to do with anything I have posted, or with anything posted or stated by any other member of my organization? That these conspiracy theories are entirely the fancies of the *opponents* of platygaeanism. In particular I have never posted any article supporting a conspiracy theory (yet :-)). This sort of nonsense has no place in a rational and honest discussion. So why don't those who understand nothing of either platygaeanism or round-earthism, and those who wish to advance their cause by attacking statements that I have *not* made, either reform themselves or stay out of the discussion. Thanx. By the way, Ronald, I don't mean to single you out too much, you were just a handy example. Many others would have served as well. And don't think I think you're a jerk in general. Everyone occassionally shoots his mouth off about things he knows nothing about. Peace. / Bret Jolly (bo'-ret tro ly) Mathemagus LA platygaean society .
ram@elmgate.UUCP (Randy Martens) (12/17/87)
In article <9901@shemp.UCLA.EDU> troly@CS.UCLA.EDU (Bret Jolly) writes: >The net.debate on platygaeanism seems to have 3 sides. Platygeanism, >rational round-earthism, and irrational hysterical round-earthism. I >propose to get rid of this last group by flaming them out. [mindless drivel deleted] >Numerous flames have been posted to the net about supposed conspiracy >theories involving Communists, Secular Humanists (whatever they are), >the CIA, the Bermuda triangle, The US army, Yetis, LSD experiments, >Steven Spielberg(!), the AMA, the "sexist/war-mongering elite",... >(I'm sure the Illuminati and the Vogons will pop up tomorrow :-) ). >Gosh, platygaeanism sure looks kooky with all those paranoid theories, >doesn't it. But has anyone noticed that all those theories have nothing >to do with anything I have posted, or with anything posted or stated >by any other member of my organization? That these conspiracy theories >are entirely the fancies of the *opponents* of platygaeanism. In particular >I have never posted any article supporting a conspiracy theory (yet :-)). >Bret Jolly (bo'-ret tro ly) Mathemagus LA platygaean society Dear Mr. Jolly, As the official spokesbeing for the Ancient and Venerable Society of the Vogon Illuminatus and Poets Union, I object to your comparing us to your idioitic organization. At least we don't attempt to deny the laws of physics. Your bunch of cretinous drivelers does. The Earth is roughly spherical, and that is all that there is to it. Anyone who attempts to deny this fact has obviously under gone a full cerebrumectomy. But please continue your senseless postings on the topic. It gives us something to write poetry about, and allows us to continue to marvel at the incredible stupidity of some members of your primitive ape-desecended race. Sincerely, Gra-gunt Flavolititiak, Chief Poet and Executioner N.B. They threatened to build a hyper-space bypass through my front yard if I didn't post this for them. But I agree with most of what they had to say. - Randy - * Randy Martens ||| "Reality - What a Concept!" - R.Williams * path : rochester!kodak!elmgate!ram * disclaimer : The preceeding represents only my random babbling, * and certainly reflects no one else's opinions. Fnord.
troly@CS.UCLA.EDU (12/17/87)
In article <1359@quad1.quad.com> oleg@quad1.quad.com (Oleg Kiselev) writes: >Nonsense. If the Earth REALLY were flat I'd be able to get KPFA (a Pacifica >FM radio station in San Francisco) anywhere in the country, particularly here, >in LA. ;-) > Thanks to our friend the ionosphere you probably could get it with a suitable antenna system. Though I don't know why you would *want* to. :-) Seriously, the `problem' you describe has the same resolution as the horizon illusion. Namely, that electromagnetic radiation does not travel in straight lines (at least) through the atmosphere. Interestingly enough this is also accepted in a way by round earth theorists, but they have the rays bending the wrong way order to follow the supposedly curved earth! I bring this up again because Dale Worley still wants to bend light the wrong way in his reply to your article. >And the OTHER question someone brought up -- where does the Sun GO when it dips >below the horizon and how does it get back? (I'd love to hear an answer to >THAT!) The problem is not the lack of an answer but that there are so many plausible answers. There are a plethora of platygaean cosmologies and we platygaean scientists must winnow them down in order to get at the truth. I shall post a summary of the major theories someday when I have time, but I would like to note that many of them consider the earth's surface to be a compact 2-dimensional manifold, just as the round earthers do. But a compact manifold (without boundary) can still be flat. Round-earthers are always confusing topological and metrical arguments. They also confuse extrinsic and intrinsic geometry. For example, Phil Wayne, who apparently is a round-earther boldly toying with platygaeanism, suggests a projective plane as the surface of the earth. This is one of the major compact models (actually it leads to a whole class of models). But Phil's description involves *twisting* and *connecting* the edges in 4 dimensions. At least I think that is what he is trying to say. (Correct me Phil, if I am misrepresenting you.) But a manifold need not be embedded in *any* euclidean space. Things get worse when round-earthers 1) Automatically embed any manifold you talk about in some euclidean space, and 2) then proceed to borrow the *metric* of that euclidean space without even realizing what they're doing. Well, I think I'll sit back and watch the discussion for a while. Hopefully some intelligent knowledgeable people like Miriam Nadel will soon join in. >Oleg Kiselev -- oleg@quad1.quad.com -- {...!psivax|seismo!gould}!quad1!oleg / Bret Jolly (bo'-ret tro ly) Mathemagus LA platygaean society .
grayson@jell-o (Matthew Grayson) (12/18/87)
In article <9959@shemp.UCLA.EDU> troly@CS.UCLA.EDU (Bret Jolly) writes: .... more flat earth stuff >a summary of the major theories someday when I have time, but I would like >to note that many of them consider the earth's surface to be a compact >2-dimensional manifold, just as the round earthers do. But a compact manifold >(without boundary) can still be flat. Round-earthers are always confusing >topological and metrical arguments. They also confuse extrinsic and intrinsic >geometry. >For example, Phil Wayne, who apparently is a round-earther boldly toying >with platygaeanism, suggests a projective plane as the surface of the earth. >This is one of the major compact models (actually it leads to a whole class >of models). That does it. You guys have blown your cover. A projective plane cannot be given a flat metric. Not intrinsicly, anyway. If you want it to be extrinsically flat, then it must be embedded (I'm assuming you don't claim that the Earth intersects itself) in a higher dimensional positively curved manifold. If you insist that the earth's surface be flat in the metric sense, then your only possible non-singular structures for compact complete 2-manifolds are tori and Klein bottles. Since no-one has travelled the earth and come back reversed, we can conclude that the torus is the only possibility. Very good. Please be kind enough to tell us where the non-trivial loops are. What path on the earth's surface does not bound a disk. What's that ? I'm getting topological? Oh. Well, suppose that every loop CAN be contracted, then the surface is a sphere, but then.. oh dear... oh my.. you're back with a round earth, which may have zero extrinsic curvature, but then there's that positively curved 3-manifold again. What's your choice? BTW. A projective plane has a non-contractible loop. Where is it? > But Phil's description involves *twisting* and *connecting* the >edges in 4 dimensions. At least I think that is what he is trying to say. >(Correct me Phil, if I am misrepresenting you.) But a manifold need not >be embedded in *any* euclidean space. But it can be, even isometrically ( see John Nash's embedding theorem). >Things get worse when round-earthers >1) Automatically embed any manifold you talk about in some euclidean space, >and >2) then proceed to borrow the *metric* of that euclidean space without even >realizing what they're doing. It's called the induced metric, and some people even realize it. Like it or not, the surface of the earth which seems flat is embedded in some 3-manifold which seems even flatter, namely an open neighborhood of the surface, so maybe embedding the earth in euclidean space is not such a bad idea, or is the fact that the volume of space near the earth's surface seems to be metrically flat insufficient to conclude that it is (hee hee). Well then, suppose that it's not euclidean 3-space. It's some flat 3-manifold. We're back to non-trivial loops. Where are they? I thought this theory was supposed to be simpler.... >Well, I think I'll sit back and watch the discussion for a while. Hopefully >some intelligent knowledgeable people like Miriam Nadel will soon join in. > >> / >Bret Jolly (bo'-ret tro ly) Mathemagus LA platygaean society > . OK, flat earthers, is the surface of the earth intrinsically flat, extrinsically flat, or both. What 3-manifold is it embedded in, and what metric does the 3-manifold have. Let's see a model!! Matt
esj@beach.cis.ufl.edu (Eric S. Johnson) (12/18/87)
In article <9959@shemp.UCLA.EDU> troly@CS.UCLA.EDU (Bret Jolly) writes: >In article <1359@quad1.quad.com> oleg@quad1.quad.com (Oleg Kiselev) writes: >>Nonsense. If the Earth REALLY were flat I'd be able to get KPFA (a Pacifica >>FM radio station in San Francisco) anywhere in the country, particularly here, >>in LA. ;-) >> >Thanks to our friend the ionosphere you probably could get it with a suitable >antenna system. .... The iono-what???!? ionosphere?? Dont you mean the ionoplane you half-witted moronic excuse for a Artificial Stupidity program! -- In Real Life: UUCP: ...ihnp4!codas!ufcsv!beach.cis.ufl.edu!esj Eric S. Johnson II Internet: esj@beach.cis.ufl.edu University of Florida "Your species is always dying and suffering" -Q
ronald@csuchico.EDU (Ronald Cole) (12/20/87)
In article <9901@shemp.UCLA.EDU> troly@CS.UCLA.EDU (Bret Jolly) writes: >The net.debate on platygaeanism seems to have 3 sides. Platygeanism, >rational round-earthism, and irrational hysterical round-earthism. I >propose to get rid of this last group by flaming them out. >Consider a posting by Ronald Cole. I wrote >>>MATHEMATICAL CONSISTENCY DOES NOT IMPLY TRUTH. >He replied >>Then what does it imply? >Can this be serious? this is a flame? I should've gotten you a gift certificate good for 1 free flaming lesson from that Smith guy in Berserkely, but I'm too cheap. Go get a copy of the Flamer's Bible; merry Christmas anyway. > He further wrote >>Can you explain why matter has a nasty tendency to assume a spherical shape >>when in free fall? Did a flat raindrop hit you on your flat head? >!?!?!?!? This is really strange. Is he saying that the earth is round >for the same reason that water droplet is rounded? (Actually a falling >raindrop has a long attenuated tail due to air resistance.) That surface >tension forces the earth into a round shape? Or that water droplets >exemplify the "natural roundness" of nature, the bane of weight-watchers >everywhere? :-) :-) You should be sure you understand both the theories >you are attacking and those that you support before posting articles to >the net. Evidently Ronald Cole understands neither. (Cheer up, Ronald, >ignorance can be cured! :-) ) The latter half of my my outburst was a poor attempt at a "flat-lander" joke. I am saying the first part of the latter of your assumptions; a sphere is the shape assumed by nature in order to maximize the ratio of volume to surface area in the absence of external forces, obviously the force of surface tension in a falling drop of water is greater than the forces due to air resistance. For the Earth, gravity is the dominant force. What new (unknown) force keeps nature from whacking the Earth with this double-whammy? I was hoping that you would clue me into something I might be missing regarding platygaeanism; however, it appears that this posting one again lacks the requisite information, increasing the entropy of information on the net. But then again, isn't that what this news group is for? ;^} In this day of high technology, I find it difficult to believe that the earth is flat. Is there some kind of magical force that keeps us from flying to its edges and observing them? Are the edges bounded by earth or ocean? If by ocean, then what keeps the oceans from pouring themselves into the ether like an overfilled bathtub, or is the Earth actually _like_ a bathtub (concave instead of flat)? If there are no edges, then is the earth an infinite plane? How thick is this slab of Earth? Arrrgh! Too many new problems to deal with! Personally, Occam's razor gives _me_ a better shave. [ dweebery about Communists, Secular Humanists, etc... mercifully deleted ] >This sort of nonsense has no place in a rational and honest discussion. >So why don't those who understand nothing of either platygaeanism or >round-earthism, and those who wish to advance their cause by attacking >statements that I have *not* made, either reform themselves or stay out >of the discussion. Thanx. >By the way, Ronald, I don't mean to single you out too much, you were just >a handy example. Many others would have served as well. And don't think >I think you're a jerk in general. Everyone occassionally shoots his mouth >off about things he knows nothing about. Peace. Maybe I just hit closer to the mark than the others. Why you singled _me_ out to flame about the "irrational hysterical" ravings of others doesn't make much sense. Otherwise, in attributing the ravings of others to me, _you_ have committed the faux pas of "attacking statements that I have *not* made". Since this sputtering flame doesn't deserve to continue in this group and I don't read talk.religion.newage.closed-mind, let's take it to Email. Ok by U? -- Ronald Cole | uucp: ihnp4!csun!csuchico!ronald AT&T 3B5 System Manager | PhoneNet: ronald@csuchico.edu California State University, Chico | voice (916) 895-4635 "... and if you don't like it, you must lump it." -Joseph Smith
malc@tahoe.unr.edu (Malcolm L. Carlock) (12/20/87)
In article <9959@shemp.UCLA.EDU> troly@CS.UCLA.EDU (Bret Jolly) writes: >In article <1359@quad1.quad.com> oleg@quad1.quad.com (Oleg Kiselev) writes: >>Nonsense. If the Earth REALLY were flat I'd be able to get KPFA (a Pacifica >>FM radio station in San Francisco) anywhere in the country, particularly here, >>in LA. ;-) >> >Thanks to our friend the ionosphere you probably could get it with a suitable >antenna system. Sorry Bret, but it's AM (lower frequency) transmissions that bounce off the ionosphere, not FM. Of course, if electromagnetic waves travel along curved paths, as you suggest, then even without the ionosphere I should be able to pick up KPFA (and WFMT from Chicago) here in Reno, since the transmissions from these stations should be curving gracefully right over the tops of the Rockies to the east, and the Sierras to the west. Interestingly, my FM receiver can't seem to pick up these stations, although on nighttime AM I can pick up Omaha, Nebraska and points east. If those ol' electromagnetic waves are a-curvin', they sure ain't a-curvin' toward little ol' me! Oh, and by the way, could you please explain what it is that determines the radii of curvature of the (allegedly) curved paths that electronic waves (allegedly) follow? If some of us here in Reno could install a device that that could curve those waves toward us (other than a golfball-sized black hole, or are black holes not recognized under platygaeanism?), maybe we could get a wider variety of FM programming around here. Thanks in advance . . . Malcolm L. Carlock ------------------------------------------------------------------------- The Timesharer's Motto: "Batches?! We don't need no stinking batches!!" ------------------------------------------------------------------------- malc@tahoe.unr.edu.UUCP University of Nevada, Reno Long live KUNR-FM (NPR-affiliate) !!
oleg@quad1.quad.com (Oleg Kiselev) (12/22/87)
BTW, why t.r.newage, Bret? Follow-ups go to alt.flames. In article <9959@shemp.UCLA.EDU> troly@CS.UCLA.EDU (Bret Jolly) writes: >>If the Earth REALLY were flat I'd be able to get KPFA (a Pacifica >>FM radio station in San Francisco) anywhere in the country, particularly here, >>in LA. ;-) >Thanks to our friend the ionosphere you probably could get it with a suitable >antenna system. Though I don't know why you would *want* to. :-) I was very deliberate in mentioning "FM". Or I could have used micro-wave, or IR communications equipment as my example. I recall that ionosphere does not reflect EM radiation of frequencies that high. >Seriously, >the `problem' you describe has the same resolution as the horizon illusion. >Namely, that electromagnetic radiation does not travel in straight lines (at >least) through the atmosphere. Interestingly enough this is also accepted in >a way by round earth theorists, but they have the rays bending the wrong way >order to follow the supposedly curved earth! The "curving" due to refraction? Come on, Bret, look up (or measure!) the index of refraction of light in air and calculate the distances needed to achieve the "bending" you are requiring. Trust me, I had driven to San Francisco and back -- it's not THAT far. >>where does the Sun GO when it dips >>below the horizon and how does it get back? >The problem is not the lack of an answer but that there are so many plausible >answers. Please, amuse us, Bret! Post your answers. (HA! Don't hold your breath!) -- Oleg Kiselev -- oleg@quad1.quad.com -- {...!psivax|seismo!gould}!quad1!oleg HASA, "A" Division DISCLAIMER: I don't speak for my employers.
alleng@killer.UUCP (Allen Gwinn) (12/22/87)
In article <829@tahoe.unr.edu> malc@tahoe.unr.edu.UUCP (Malcolm L. Carlock) writes: >Sorry Bret, but it's AM (lower frequency) transmissions that bounce off the >ionosphere, not FM. I'll have to remember that, Malcolm, the next time I use my aircraft radio (+- 110-130 MHz AM). To think that I might have been cleared for takeoff by L.A. Tower when I was in Dallas makes me mighty nervous :-) And while I'm at it, I have decided to junk my 10 Meter FM amateur radio transceiver since you have convinced me that FM signals don't bounce off of the ionosphere (or ionoplane :-) ). '73 All... :-) -- Allen Gwinn / email: {ihnp4!decvax!killer}!sulaco!allen \ USPS: P.O. Box 740444, Dallas, TX 75374-0444
troly@CS.UCLA.EDU (12/28/87)
In article <1471@cartan.Berkeley.EDU> ir353@sdcc6.ucsd.edu (Matthew Grayson) writes: >That does it. You guys have blown your cover. A projective plane cannot be >given a flat metric. Not intrinsicly, anyway. If you want it to be >extrinsically flat, then it must be embedded (I'm assuming you don't >claim that the Earth intersects itself) in a higher dimensional positively >curved manifold. If you insist that the earth's surface be flat in the >metric sense, then your only possible non-singular structures for compact >complete 2-manifolds are tori and Klein bottles. This is quite true (courtesy of the Gauss-Bonnet theorem). We could have a projective plane which is pretty flat except in one locality (the Bermuda triangle? :-)), but I agree that this is not morally flat. However I don't completely reject it out of hand for that reason. The LA Platygaean Society considers all sorts of possibilities, indeed some of our members are round-earthers. But the appeal of the projective plane lies in something apart from Riemannian geometry. If there is one thing we know from round-earth based physics it is the power of duality. Consider coordinates and conjugate momenta in Hamiltonian mechanics, Legendre transforms in Thermodynamics, not to mention the Heisenberg uncertainty principle in quantum mechanics. Like Yin and Yang, yes, there is a Tao of physics! And might not this duality spring from some geometrical basis of the world we live in? Projective geometry embodies duality from the most basic level. But this is not metric, the theory would eventually have to explain our perception of physical distance in terms of fundamental incidence relations. There is good reason to consider distance to be an epiphenomenon, even in conventional round-earth worldviews. Topological or incidence relations are much more fundamental. Personally I am not (currently) a projective planer but I think the theory deserves the same level of critical consideration that I give to platygaean theories. If the ancient Greeks had taken a modern view and Euclid had written his Elements on topology and projective geometry the subsequent history of science would have been much different. But the Greeks could not even imagine geometry aside from that imbedded in Euclidean 3-space. > Since no-one has travelled the earth and come back reversed, we can > conclude that the torus is the only possibility. WAITAMINNIT! There are plenty of non-orientation reversing paths "around" a Klein bottle earth. > Very good. Please be kind enough to tell us where the >non-trivial loops are. What path on the earth's surface does not bound a disk. This seems very difficult experimentally. I'd need to mount many worldspanning expeditions, a heck of a lot of thread, and a way of pulling it taut without breaking it :^). >What's that ? I'm getting topological? Oh. Well, suppose that every loop >CAN be contracted, then the surface is a sphere, but then.. oh dear... oh my.. Exercise: Prove the analogous result for a 3-sphere :^) :^) :^). Recommended reading for all, no matter what shape you think the earth is, THE SHAPE OF SPACE by Jeffrey R. Weeks. (Pub. Marcel Dekker). Mind-stretching! > BTW. A projective plane has a non-contractible loop. Where is it? I found it! (No spoiler). > {Matt quoting me} >>(Correct me Phil, if I am misrepresenting you.) But a manifold need not >>be embedded in *any* euclidean space. {he replies} > But it can be, even isometrically ( see John Nash's embedding theorem). I said *need* not be ... >OK, flat earthers, is the surface of the earth intrinsically flat, >extrinsically flat, or both. What 3-manifold is it embedded in, and what >metric does the 3-manifold have. Let's see a model!! If I figure this out I'll try to write my thesis on it :^). This discussion has drifted far from the new age issues I originally addressed so I move that followups be directed to alt.flame. Unfo
ethan@ut-emx.UUCP (Ethan Tecumseh Vishniac) (12/31/87)
In article <10064@shemp.UCLA.EDU>, troly@CS.UCLA.EDU writes: > {Various literate, sophisticated and ridiculous arguments in favor of a flat Earth deleted, but admired.} These are wonderful articles, but I am greatly puzzled by one thing. They are obviously meant to be satire, but the articles that they most effective satirize are to be found in talk.origins, which is *omitted* from the newsgroup list. Why? Frankly, alt.flame is a poor substitute. -- I'm not afraid of dying Ethan Vishniac, Dept of Astronomy I just don't want to be {charm,ut-sally,ut-ngp,noao}!utastro!ethan there when it happens. (arpanet) ethan@astro.AS.UTEXAS.EDU - Woody Allen (bitnet) ethan%astro.as.utexas.edu@WISCVM.WISC.EDU
oleg@quad1.quad.com (Oleg Kiselev) (01/07/88)
In article <2534@killer.UUCP> allen@sulaco.UUCP (Allen Gwinn) writes: >>... it's AM (lower frequency) transmissions that bounce off the >>ionosphere, not FM. >I'll have to remember that, Malcolm, the next time I use my aircraft >radio (+- 110-130 MHz AM). To think that I might have been cleared for >takeoff by L.A. Tower when I was in Dallas makes me mighty nervous :-) > >And while I'm at it, I have decided to junk my 10 Meter FM amateur radio >transceiver since you have convinced me that FM signals don't bounce off >of the ionosphere (or ionoplane :-) ). Lest some other poor souls get confused by all this (I assume Allen knows wherefor he speaks, as seems to be indicated by the smilies): AM and FM refer to the method of information "encoding" and transmission, rather than the frequency of the carrier wave. Unfortunately, for most people not well informed FM has become synonimous with 88-108 MHz carrier frequency. And the same way AM became sysnonimous with 530-1600 KHz. Which is rather sad, because AM and FM, although being preferred modulation methods at certain distinct frequency ranges, are not frequency specific. So, in discussing ionosurface (;-) reflections of E&M waves, the frequency and not modulation methods should be kept in mind. And yes, signals at 100+ MHz (AM or FM) will not bounce off the ionosphere, while 10 Meter (30 MHz?) very well may be reflected. -- Oleg Kiselev -- oleg@quad1.quad.com -- {...!psivax|seismo!gould}!quad1!oleg HASA, "A" Division DISCLAIMER: I don't speak for my employers.
rjp1@ihlpa.ATT.COM (01/09/88)
In article <1414@quad1.quad.com>, oleg@quad1.quad.com (Oleg Kiselev) writes: >In article <2534@killer.UUCP> allen@sulaco.UUCP (Allen Gwinn) writes: >>> ... it's AM (lower frequency) transmissions that bounce off the >>> ionosphere, not FM. >> >> I'll have to remember that, Malcolm, the next time I use my aircraft >> radio (+- 110-130 MHz AM). To think that I might have been cleared for >> takeoff by L.A. Tower when I was in Dallas makes me mighty nervous :-) >> >> And while I'm at it, I have decided to junk my 10 Meter FM amateur radio >> transceiver since you have convinced me that FM signals don't bounce off >> of the ionosphere (or ionoplane :-) ). > > Lest some other poor souls get confused by all this (I assume Allen knows > wherefor he speaks, as seems to be indicated by the smilies): > > AM and FM refer to the method of information "encoding" and transmission, > rather than the frequency of the carrier wave. Unfortunately, for most people > not well informed FM has become synonimous with 88-108 MHz carrier frequency. > And the same way AM became sysnonimous with 530-1600 KHz. Which is rather sad, > because AM and FM, although being preferred modulation methods at certain > distinct frequency ranges, are not frequency specific. > > So, in discussing ionosurface (;-) reflections of E&M waves, the frequency and > not modulation methods should be kept in mind. And yes, signals at 100+ MHz > (AM or FM) will not bounce off the ionosphere, while 10 Meter (30 MHz?) very > well may be reflected. > -- > Oleg Kiselev -- oleg@quad1.quad.com -- {...!psivax|seismo!gould}!quad1!oleg SO, WHY IS THIS IN TALK.RELIGION.NEWAGE??????
ray@micomvax.UUCP (Ray Dunn) (01/09/88)
In article <2534@killer.UUCP> allen@sulaco.UUCP (Allen Gwinn) writes: >In article <829@tahoe.unr.edu> malc@tahoe.unr.edu.UUCP (Malcolm L. Carlock) writes: >>Sorry Bret, but it's AM (lower frequency) transmissions that bounce off the >>ionosphere, not FM. > >I'll have to remember that, Malcolm, the next time I use my aircraft >radio (+- 110-130 MHz AM). To think that I might have been cleared for >takeoff by L.A. Tower when I was in Dallas makes me mighty nervous :-) > >etc. etc. OK guys already!! Lets try & end this before it starts a landslide! Allen, why clutter us up with sarcasm (only) when you KNOW what Malcolm really meant! The important factor is not AM or FM but *WAVELENGTH*. Teeny waves shoot through the ionosphere (or Heavyside (or is it Appleton) layer (:-)), long waves bounce off (then bounce off the earth again, and so on ...). Wavelength is inversely proportional to the *FREQUENCY* of the signal. meters = 3*10^8/Hz It so happens that what all non-techies call "FM" (i.e. transmissions from "domestic" *F*requency *M*odulated radio stations) is broadcast on the so called, *V*ery *H*igh *F*requency band, and thus has a very short wavelength (around 3 meters). Normal domestic "AM" (*A*mplitude *M*odulation) stations broadcast on the Medium Wave band, around 190 to 580 meters. I'm surprised at your 10meter comment. As I remember, the transition from bounce to no-bounce takes place at about 18Mhz, i.e. 16 meters, so 10meters talks to the stars! Ray Dunn. ..philabs!micomvax!ray
dhesi@bsu-cs.UUCP (Rahul Dhesi) (01/15/88)
In article <875@micomvax.UUCP> ray@micomvax.UUCP (Ray Dunn) writes: >I'm surprised at your 10meter comment. As I remember, the transition from >bounce to no-bounce takes place at about 18Mhz, i.e. 16 meters, so 10meters >talks to the stars! Most times a 10-meter the transmission won't get reflected, but under certain weather conditions some might. I spent many happy years listening to a distant BBS relay station at around 11 meters. -- Rahul Dhesi UUCP: <backbones>!{iuvax,pur-ee,uunet}!bsu-cs!dhesi