Bass in audio is good
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In reply to this post by Geoffrey Mackenzie-Kennedy
> 'Information rate' is I suppose the let-out. Information rate is not a "let out" in analog voice. > I would have thought that the use of ESSB would come close to > breaking the rules on Emission Standards as imposed by some > regulators, e.g. FCC Amateur Rules section 97.307 which says > in part 'No amateur station transmission shall occupy more > bandwidth than necessary for the information rate and > emission type being transmitted, in accordance with good > amateur practice'. This is key and should be enforced. Many years ago Bell Labs (and others) proved rather thoroughly that 2.4 to 2.6 KHz was more than adequately for "communications" purposes. Their tests were specifically in relation to "toll grade" audio for long distance telephony. The FCC rules specifically required a maximum bandwidth of 2.6 KHz on the US 60 meter channels. That should provide a strong example of what FCC and NTIA consider to be the "maximum bandwidth necessary" for single sideband operation in amateur allocations. Most amateur transceivers use 2.4 KHz bandwidth filters for SSB generation - even cascaded 2.4 KHz filters with an effective bandwidth in the 2.2 KHz range. The default SSB transmit bandwidth for the K3 should be 300 - 2900 Hz or 200 - 2800 Hz in order to not be excessively wide and meet the FCC regulations for use on the US 60 meter allocation. 73, ... Joe, W4TV > -----Original Message----- > From: [hidden email] > [mailto:[hidden email]] On Behalf Of > Geoffrey Mackenzie-Kennedy > Sent: Monday, May 05, 2008 2:37 PM > To: Elecraft Discussion List > Subject: Re: [Elecraft] Bass in audio is good > > > Ian J Maude <[hidden email]> wrote: > > > Good idea, give them 5kHz :-) > > > > Sorry, I could not resist! > > I would have thought that the use of ESSB would come close to > breaking the > rules on Emission Standards as imposed by some regulators, > e.g. FCC Amateur > Rules section 97.307 which says in part 'No amateur station > transmission > shall occupy more bandwidth than necessary for the > information rate and > emission type being transmitted, in accordance with good > amateur practice'. > 'Information rate' is I suppose the let-out. > > 73, > Geoff > GM4ESD > > _______________________________________________ > Elecraft mailing list > Post to: [hidden email] > 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 _______________________________________________ Elecraft mailing list Post to: [hidden email] 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 |
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In reply to this post by ab2tc
More Bass on my fish stringer, is better.
John k7up _______________________________________________ Elecraft mailing list Post to: [hidden email] 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 |
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In reply to this post by Mike Scott-7
In a message dated 5/5/08 5:14:48 PM Eastern Daylight Time,
[hidden email] writes: > Many years ago Bell Labs > (and others) proved rather thoroughly that 2.4 to 2.6 KHz > was more than adequately for "communications" purposes. Their > tests were specifically in relation to "toll grade" audio for > long distance telephony. Which is *not* amateur radio communication! Things like QRM, QRN and selective fading are not usually encountered in landline telephones. Note also that despite the quality standards, people often have to repeat themselves on the telephone, spell out words and names, etc. > > The FCC rules specifically required a maximum bandwidth of 2.6 > KHz on the US 60 meter channels. That should provide a strong > example of what FCC and NTIA consider to be the "maximum > bandwidth necessary" for single sideband operation in amateur > allocations. No, they shouldn't. The 60 meter channels are shared with other services. Amateurs are secondary users there, and must conform to the primary user's standards. > > Most amateur transceivers use 2.4 KHz bandwidth filters for > SSB generation - even cascaded 2.4 KHz filters with an effective > bandwidth in the 2.2 KHz range. The default SSB transmit bandwidth > for the K3 should be 300 - 2900 Hz or 200 - 2800 Hz in order to > not be excessively wide and meet the FCC regulations for use on > the US 60 meter allocation. Agreed! But that's only on 60 meters. Should we stop using LSB because other services don't generally use it? Should we channelize our bands because that's what other services do? I say there's room for all. 73 de Jim, N2EY ************** Wondering what's for Dinner Tonight? Get new twists on family favorites at AOL Food. (http://food.aol.com/dinner-tonight?NCID=aolfod00030000000001) _______________________________________________ Elecraft mailing list Post to: [hidden email] 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 |
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In reply to this post by Joe Subich, W4TV-3
You meant to say "affect other modes" Joe, not effect.
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In reply to this post by Joe Subich, W4TV-3
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