Grant has this correct!! for those that doubt, ask youself this. How often do I use phonetics when speaking face to face? And why not? Ans. BECAUSE YOU ARE HEARING THE FULL SPECTRUM! Bernie W8RPW----- Original Message ----- From: "Grant Youngman" <[email protected]> To: "Discussion of AM Radio in the Amateur Service" <[email protected]> Sent: Tuesday, September 15, 2009 2:31 PM Subject: Re: [AMRadio] AM Transmitter "quality"
> > On Sep 15, 2009, at 1:11 PM, Joe Hankins wrote: > >> I >> operation was effective radiotelephone service. Human speech falls >> into >> the range between 300 and 3000 Hz. There are sounds outside this >> range, >> but they do not contribute to intelligibility. > > That's actually a complete myth. There are frequency components both > above and below this range which, if present, contribute in a major > way to speech intelligibility. The fundamental frequency in vowels > is closer to 100 Hz, and frequencies well above 3 Khz (actually above > 4Khz) are needed to reliably distinguish an "f" from an "s". There > are also significant intelligibility cues in the 20-80Hz range for > some consonants. > > 300-3000 hz was convenient for the phone company and was proselytized > by Collins (which we all know is never incorrect in design philosophy) > as the gospel truth. But it contributed mostly to Uncle Bob and > Granny being so hard to understand and sounding so lousy on the > telephone. And contributes still to "pinched" sounding radios. Your > modern telephone (fortunately) exceeds this old accepted range in > bandwidth. > > Grant/NQ5T > ______________________________________________________________ > Our Main Website: http://www.amfone.net > AMRadio mailing list > Searchable Archives: http://www.mail-archive.com/[email protected]/ > List Rules (must read!): http://w5ami.net/amradiofaq.html > List Home: http://mailman.qth.net/mailman/listinfo/amradio > Post: [email protected] > To unsubscribe, send an email to [email protected] with > the word unsubscribe in the message body. > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > ______________________________________________________________ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/[email protected]/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Post: [email protected] To unsubscribe, send an email to [email protected] with the word unsubscribe in the message body. This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
