> If you'd like to read one of many reasonably balanced views > of the use of ESSB, check this web site. I don't know the > fellow, but from what I've read of his site, I agree with him. > > http://www.icycolors.com/nu9n/apologetics_2.html > > But then, I tend to agree with most who speak in terms of > moderation...
That site is full of misinformation and is hardly "moderation." Many years ago AT&T (Bell Labs) proved rather conclusively that an audio bandwidth of less than 3 KHz (generally about 2.4 - 2.7 KHz) was all that was necessary for reasonable "communications quality" or "tool grade" voice. Most communications services - including government HF voice circuits and the US amateur rules for 60 Meters - are based on 2.5 KHz "Channels" (2K4J3E USB with a slight "guard band"). That makes a very good standard against which to judge "minimum necessary bandwidth" - particularly on a crowded band. There is no communications requirement for a 6 (or even 5) KHz audio bandwidth - that's equivalent to the old "remote broadcast lines" that Ma Bell made available only on a limited basis through much of the history of analog telephony. Anyone who makes the "AM requires 6 KHz" argument is comparing apples and oranges. 6 KHz AM (6K00A3E) represents a highest modulating frequency of 3 KHz - comparable to 2K70J3E! Most amateurs will relax the minimum bandwidth a little and accept 2.7 or 2.8 KHz vs. 2.4 KHz at the 6 dB points. That represents an audio response of 200 Hz or 300 Hz to 3 KHz. However, there is no intelligent reading of Part 97 that supports (justifies) the use of 4K00J3E, 5K00J3E or 6K00J3E any more than it will support 8K00A3E (8 KHz wide AM - 100 Hz to 4 KHz audio) or 10K00A3E (10 KHz wide AM - 100 Hz to 5 KHz audio). The ESSB argument is nothing more than a small group of individuals saying "I will do it because I have the technology to do it." That's the same as saying "I'm going to drive 160 MPH on the interstate because my car can go that fast." It's a dangerous, selfish and short sighted attitude. 73, ... Joe, W4TV _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
