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#31
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On Mon, 20 Apr 2009 23:02:59 -0700, Greegor wrote:
A 5-tubes superhet receiver made in Japan about 1955. Notwithstanding I didn't see this line at http://en.wikipedia.org/wiki/Superheterodyne_receiver , when I was a kid, we had an "All-American Five" WELL before 1955. http://en.wikipedia.org/wiki/All_American_Five Hope This Helps! Rich |
#32
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On Apr 21, 5:34�am, Tim Shoppa wrote:
On Apr 21, 1:05�am, "Phil Allison" wrote: "AF6AY" Everyone ought to realize that "Wikipedia" data can be written by ANYONE ** As are NG posts. The difference being that Wikis are full of checkable references and are subject to on-going correction. The best Wikipedia articles are often filled with good checkable references, but other times it sounds like they were written in a foreign language and translated into English and have few (if any) good references. One can write just about anything so that it looks good and authentic. :-) There is plenty of rather authentic information on Edward Howard Armstrong, including scans of Armstrong's patents. As to the words "supersonic" and "subsonic" I doubt that those were coined prior to around 1930, rather long after the superheterodyne came into being as the very model of a modern major receiver structure. Argument over the 'super' prefix/designator would come a cropper on things like the super-regenerative receiver which use a sort of burst oscillation at frequencies quite higher than young adult hearing maximum of 15 KHz, i.e., "supersonic" in terms of frequency. In aerospace, "supersonic" is a term for going faster than the speed of sound. As to "typically converting the signal frequency below the range of tuning," that WAS true but it applies only to most superhets that were designed prior to WWII (at least 60 years ago). Those mixers used only the difference frequency output while the sum frequency output just dissipated internally. That changed with UP-conversion, notably in Collins Radio designs for their lowest selectable bands, then in the first wideband spectrum analyzers covering a full GHz in one sweep. Those early spectrum analyzers would up-convert 0 to 1 GHz to a 2 GHz first IF, then down-convert from there. 2 GHz is so far above 'supersonic' that it would be a misuse of it. Somewhere there's a bunch of people who spend their time correcting and improving Wikipedia entries, and I think overall they are doing a good job, but that doesn't mean the result is always devoted to my interests. Just like anything else in this world, it's got workers and it's got managers and they aren't always devoting their attention to the little corners of arcania that I live in. There's also a lot more folks who just vent their frustrations on everyone else, such as Phil Allison (who's profile can't be accessed because he violated the Terms of Service on Google). As to the ORIGIN of technical terms, speaking as a lifetime engineer and technician and worker IN engineering, it matters little as to etymology but a great deal more on the SUBJECT the word is referring to. If anyone wants to think "supersonic" applied in 1918 to anything at all, then they are welcome to point out the "supersonic" aircraft of that time...made of pieces of steel, wood, wire, and fabric. :-) It was a long time between 1918 and 1947 when the first aircraft broke the 'sound barrier' (Bell X-1 piloted by Chuck Yeager). 73, Len AF6AY |
#33
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Jean-Christophe wrote:
On Apr 20, 5:50 pm, Tim Shoppa wrote: A terminology question I suppose about the derivation of the term "Superheterodyne" more than anything else: Does the "Super" actually mean anything? Is there a Subheterodyne? Traditionally superhets mix a higher radio frequency down to a lower IF frequency, but certainly in the past few decades radios with IF's above the RF frequency have become very common in broadband applications, and those are still called superhets, not subhets :-). Google turns up a couple hits on subheterodyne but other than one that might mean "IF higher in frequency than RF" I don't recognize what they mean.. A superheterodyne can be Supradyne or Infradyne, depending of the IF against the RF. I suspect that "Super" was more a marketing term than anything else :-). I don't superthink so. There was a type of circuit called the 'heterodyne', which is actually just a direct conversion receiver. Adding the IF stage made it a 'super' heterodyne. Also remember the 'super-regenerative' circuit? That was an improvement over the regenerative receiver in that feedback could be increased past the self oscillation point to get even more gain via the use of a supersonic quench oscillator. So maybe the prefex DOES refer to supersonic. |
#34
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P
Is there a Subheterodyne? ** No. But if you wind your tickler coil bass-ackwards you end up with a degenerative receiver circuit. |
#35
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![]() "AF6AY" = radio ham nutter One can write just about anything so that it looks good and authentic. :-) ** Shame how that leaves this retarded old ham out in the cold. As to the words "supersonic" and "subsonic" I doubt that those were coined prior to around 1930, ** So the clot has no idea what terms were in use back then at all - but it suits him to pretend that he knows. What a hee-hawing bloody ASS. ....... Phil |
#36
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TheM wrote:
"Robert Baer" wrote in message net... Joerg wrote: John Larkin wrote: On Mon, 20 Apr 2009 12:36:12 -0700, Joerg wrote: Tim Shoppa wrote: A terminology question I suppose about the derivation of the term "Superheterodyne" more than anything else: Does the "Super" actually mean anything? Is there a Subheterodyne? Traditionally superhets mix a higher radio frequency down to a lower IF frequency, but certainly in the past few decades radios with IF's above the RF frequency have become very common in broadband applications, and those are still called superhets, not subhets :-). Google turns up a couple hits on subheterodyne but other than one that might mean "IF higher in frequency than RF" I don't recognize what they mean.. I suspect that "Super" was more a marketing term than anything else :-). If you want to file a new patent for old stuff you could try subheterodyne and it just might sail through :-) Oh wait, call it hyperheterodyne, has more glitz. Just like the supermercados in Spain. I meant hypermercados :-) I think we're going to be doing a superhet receiver soon. Maybe we'll do it in an FPGA! How'd you do the preamp in there? Bit shift? Yes, but 2x zero is still zero... ![]() M .... +/-3dB. -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM. |
#37
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![]() "Tim Shoppa the ****** " Greegor the Geek What specifically are your complaints with this Wiki ? http://en.wikipedia.org/wiki/Superheterodyne_receiver A 180 Kbyte article about a technology developed in the 1910's, ** Irrelevant when it was first developed - cos it is still current tech. The article is not pretending to be being a history lesson. A smaller point, is that the language sounds a lot like it was written in a language other than English and then translated. ** That is an utterly absurd idea. Smacks of paranoid schizophrenia. Shoppa has completely lost it. ...... Phil |
#38
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"Tim Shoppa the ****head Troll "
Everyone ought to realize that "Wikipedia" data can be written by ANYONE ** As are NG posts. The difference being that Wikis are full of checkable references and are subject to on-going correction. The best Wikipedia articles are often filled with good checkable references, but other times it sounds like they were written in a foreign language and translated into English ** Only indicates your lack of comprehension. Just because a Wikipedia entry isn't well-written or sounds awkward ** You are irrationally obsessed with style over content. Mostly likely because you cannot comprehend the content. Somewhere there's a bunch of people who spend their time correcting and improving Wikipedia entries, and I think overall they are doing a good job, but that doesn't mean the result is always devoted to my interests. ** What a revolting, pompous little narcissist you are - Tim. Just like anything else in this world, it's got workers and it's got managers and they aren't always devoting their attention to the little corners of arcania that I live in. ** I was much too kind earlier .... It's not that the Encyclopedia Britannica is perfect either. I can open it up to the very few subjects that I happen to be expert on and find over-simplifications and a lack of cites to what I consider to be the best references. ** Mere narcissism has just turned into full blown ego-mania. Of course in academia I got real used to opening a journal and instead of reading the articles, to go straight to the references and see if they are quoting one of my articles :-). ** Wot a nauseating computer geek puke. ....... Phil |
#39
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On Apr 21, 5:54*pm, "Phil Allison" wrote:
** *Only indicates your lack of comprehension. ** You are irrationally obsessed with style over content. ** What a revolting, pompous little narcissist you are *- ** *I was much too kind earlier .... ** *Mere narcissism has just turned into full blown ego-mania. ** Wot a nauseating computer geek puke. There is a thin line between ignorance and arrogance, Phil. I have erased that line! Tim. |
#40
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![]() "Tim Shoppa = Autistic Troll " The best Wikipedia articles are often filled with good checkable references, but other times it sounds like they were written in a foreign language and translated into English ** Only indicates an autistic lack of comprehension. Just because a Wikipedia entry isn't well-written or sounds awkward ** You are autistically obsessed with imaginary flaws in the writing. Mostly likely because you have gone quite insane. Somewhere there's a bunch of people who spend their time correcting and improving Wikipedia entries, and I think overall they are doing a good job, but that doesn't mean the result is always devoted to my interests. ** What a revolting, pompous narcissistic pig you are - Tim. Just like anything else in this world, it's got workers and it's got managers and they aren't always devoting their attention to the little corners of arcania that I live in. ** I was much too kind earlier .... It's not that the Encyclopedia Britannica is perfect either. I can open it up to the very few subjects that I happen to be expert on and find over-simplifications and a lack of cites to what I consider to be the best references. ** Mere narcissism has just turned into full blown, autistic ego-mania. Of course in academia I got real used to opening a journal and instead of reading the articles, to go straight to the references and see if they are quoting one of my articles :-). ** Shoppa's self delusions have made him a legend in his own mind. When all he really has become is " history ". ...... Phil |
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