In a message dated 8/12/07 8:39:25 AM Eastern Daylight Time, [EMAIL PROTECTED] writes:
> What is the definition of ESSB, anything greater than 2.7kHz? My > Orion2 can do up to 3000 I believe, so is this ESSB? > > No. THere's no hard-and-fast defintion of ESSB that I've seen. In practice, it means SSB 6 to 9 kHz wide or thereabouts. IMHO, the justifications for ESSB boil down to these: 1) 'ESSB sounds "better" than regular SSB'. "Better", is of course in the ear of the beholder. The questions are, does the better sound come from the wider bandwidth or from other things, like less distortion? And does sounding better justify twice the bandwoth or more? 2) 'DSB AM with carrier typically takes up 6 to 9 kHz of the band. If it's OK for that kind of AM to take up 6 to 9 kHz, why isn't it OK for a different kind of AM to do the same?" The answer is that DSB AM *has to* occupy that much space, by its very nature. SSB doesn't. 3) 'ESSB users are "experimenting" with new modes". That's a good thing, but does it justify the bandwidth? Particularly when decades of research have shown that voice comms need only 3 kHz maximum audio? Could other modes justify bandwidth-enhanced things like clicks and hum on that principle? 4) 'There's no explicit rule limiting the bandwidth of an SSB signal.' That's true - and it's a good thing. FCC has given US hams a lot of leeway in the regs, and has repeatedly avoided hard-and-fast technical rules on things like bandwidth out of trust that hams will 'do the right thing'. Abusing that trust is just begging for more and stricter regulations. The question I ask is this: What about FM? I really like FM voice. Sounds really good, the equipment is simple and there's a lot of it in use by amateurs and others. Why can't I run FM voice that's 15 or 20 kHz wide on 75 meters? I think it would sound really, really good. Much better than even AM, and immune to summer QRN. The transmitter would be very efficient, modulated at low level and amplified in highly efficient Class E stages that are very simple and don't have to be amplitude-linear at all. I'd be experimenting with new things. What's the problem? 73 de Jim, N2EY ************************************** Get a sneak peek of the all-new AOL at http://discover.aol.com/memed/aolcom30tour _______________________________________________ Elecraft mailing list Post to: [email protected] 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
