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When is a hybrid not a hybrid?
On Feb 2, 2:17 pm, "
wrote: On Feb 2, 1:23?am, "John A" wrote: wrote in message ...... Many thanks for a fascinating post, Len. John A Thank you, but most of the thanks should go to a gentleman at the Signal School that was in Fort Monmouth, NJ, back in 1952. He had spent a lot of his work time at Bell Labs. My MOS was Microwave Radio Relay in the Army and had to encompass comms techniques from landline telephone through radio at VHF to microwaves. Even more to a couple of GE technical reps who oversaw the installation of 24-voice-channel 1.8 GHz radio relay terminals in Japan '54 to '56. They had the knowledge at their mind's finger- tips and infused a number of us back then with some indelible information. :-) If you wish to see a bit more of 50-year-old military communications, download: http://sujan.hallikainen.org/Broadca...s/My3Years.pdf It's about 6 MB and takes about 20 minutes on a dial-up connection. Hal has a lot of information collected there, not all of it on broadcasting. As is so often the case with word/phrase etymology, origins are sometimes cloudy. The wikipedia article alludes to this. But I believe the key is that the two outputs are equal in a so-called "hybrid". You might simply tell your readers in summary that the issue is unclear, and that you gave it the best shot anyone reasonably can. |
#2
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When is a hybrid not a hybrid?
Thanks for all the interesting replies - particularly Len's long historical narrative - and please accept my apologies for not responding immediately. The magazine article took a different course from the one that I'd anticipated, and thus took much longer to write. After all the research and reminiscence, though, we still aren't much closer to understanding why some old-time telephone engineer named this circuit a "hybrid" . We can only speculate that, before finding his true vocation with Ma Bell, he had failed both English and Genetics. In the end it seemed more important to concentrate on the defining characteristics of a modern "RF hybrid", which are coupling between some of its ports (usually equal power division), and at the same time, isolation between other ports. Even that is more of a loose consensus than a firm definition, of course. Anyhow, the article eventually started with a fairly detailed description of the telephone hybrid (which also explains why a hybrid can sometimes be called a bridge instead) and then wandered onward to identify a few RF hybrids and describe some useful applications of RF hybrids; by which point, I had used up my two pages. Thanks again to everyone who contributed - it certainly helped to straighten out my thinking on what had originally seemed such an innocent little question. -- 73 from Ian GM3SEK 'In Practice' columnist for RadCom (RSGB) http://www.ifwtech.co.uk/g3sek |
#3
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When is a hybrid not a hybrid?
On Feb 13, 6:47�am, Ian White GM3SEK wrote:
Thanks for all the interesting replies - particularly Len's long historical narrative - and please accept my apologies for not responding immediately. The magazine article took a different course from the one that I'd anticipated, and thus took much longer to write. After all the research and reminiscence, though, we still aren't much closer to understanding why some old-time telephone engineer named this circuit a "hybrid" . We can only speculate that, before finding his true vocation with Ma Bell, he had failed both English and Genetics. In the end it seemed more important to concentrate on the defining characteristics of a modern "RF hybrid", which are coupling between some of its ports (usually equal power division), and at the same time, isolation between other ports. Even that is more of a loose consensus than a firm definition, of course. Anyhow, the article eventually started with a fairly detailed description of the telephone hybrid (which also explains why a hybrid can sometimes be called a bridge instead) and then wandered onward to identify a few RF hybrids and describe some useful applications of RF hybrids; by which point, I had used up my two pages. Thanks again to everyone who contributed - it certainly helped to straighten out my thinking on what had originally seemed such an innocent little question. -- 73 from Ian GM3SEK * * * * 'In Practice' columnist for RadCom (RSGB)http://www.ifwtech.co.uk/g3sek Heh heh heh, the etymological problems can be furthered by looking at other terms in all of electronics and how they came to be known. :-) Sometimes we just have to plain accept common terms rather than buy industrial-strength aspirin quantities to ease the ensuing headaches. "English" (our supposed 'common' language) has, like most other languages in Yurp, grown, adopted, changed, mangled, seasoned, and baked thoroughly by common folk for centuries in daily use. The only "correct" use seems to be that authorized by our school teachers... :-) How about posting in here when the publishing schedule is firm about which issue the article will appear in? [he said, mangling sentence structure] Might be a fun future topic for discussion? :-) |
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