FYI One of my ADs sent the attached item to me. I had not been aware of it even though you all may have been. Jim Weaver, K8JE Director, Great Lakes Division ARRL 5065 Bethany Rd., Mason, OH 45040 Tel. 513-459-0142, E-mail k8je@arrl.org ARRL: The reason Amateur Radio is! Members: The reason ARRL is! -----Original Message----- From: ragchewersgroup@yahoogroups.com [mailto:ragchewersgroup@yahoogroups.com] Sent: Thursday, April 14, 2005 9:26 AM To: ragchewersgroup@yahoogroups.com Subject: [Rag Chewers' Club] Digest Number 258 ------------------------ Yahoo! Groups Sponsor --------------------~--> Dying to be thin? Anorexia. Narrated by Julianne Moore . http://us.click.yahoo.com/Dtf6vA/gsnJAA/d1hLAA/0NYolB/TM --------------------------------------------------------------------~-> There is 1 message in this issue. Topics in this digest: 1. Bandwidth Proposal From: "Walter A. Breining" <n9wb@nltc.net> ________________________________________________________________________ ________________________________________________________________________ Message: 1 Date: Wed, 13 Apr 2005 16:40:43 -0000 From: "Walter A. Breining" <n9wb@nltc.net> Subject: Bandwidth Proposal The ARRL is proposing to place a petition for rulemaking before the FCC to define emission type by bandwidth. The ARRL is accepting comments and opinions on this proposal. So far the majority of the problems that have been addressed have involved digital operations. Those of us who use SSB on the Amateur frequencies below 28 MHz need to take a very close look at what is being proposed. This proposal establishes a maximum bandwidth of 3 kHz for SSB. What is not obvious in this proposal is what is meant by bandwidth. Here is the definition of bandwidth in the Part 97 FCC rules. 97.3 (a) (8) (8) Bandwidth. The width of a frequency band outside of which the mean power of the transmitted signal is attenuated at least 26 dB below the mean power of the transmitted signal within the band. Notice that 3 kHz will not be the point where the signal starts to roll off, or even the 6 dB point, it is the point where the signal must be 26 dB down on each side! To comply with this our bandwidth will have to be extremely narrow depending on the slope factor of our filters. I think you will find that with most stock filters, 2.8 kHz, 2.4 kHz, and many 2.2 kHz filters will not meet this requirement. With the common 2.5/1 slope factor of most filters that come stock in most existing Amateur Transceivers, we could not run a filter specified at a width of more than 2 kHz at the 6 dB points to meet this requirements. First, let me explain that I am not a proponent of running extremely wide bandwidth such as 10 kHz. In the days when AM radio was king, many studios were connected to the transmitter by 5 kHz equalized telephone lines. While music sounded somewhat poor by today's standards, the DJ's voices were quite good. My experience has been that intelligibility increases with bandwidth. However there is a point where the returns diminish. In my experience, this point of diminishing returns begins at about 3.5 kHz. Wider bandwidth makes the audio subtly more pleasant, but the rate of increase in intelligibility and pleasantness decreases beyond 3.5 to 4 kHz. Please note that I am talking of a flat bandwidth of 3.5 kHz not a bandwidth that is 26 dB down between points separated by 3.5 kHz. Collins started out with a bandwidth on SSB of 1.8 kHz and soon increased to 2.4 kHz filters. Most filters specify the bandwidth, as the distance between 6 dB points not 26 dB points. If this proposal passes as proposed, in order to fully comply with the rules, we will either have a narrow DX type sound like the Heil HC-4 element or a muffled sound depending on where we place the center of our band pass within the audio range. While I enjoy Dxing and Contesting, I also take pride in the way my audio sounds. Most Amateurs strive to have a good sounding station. Interest in audio quality has always been a part of Amateur Radio. To degrade and limit the quality of H.F. SSB is ill advised and will quench the enthusiasm of many Radio Amateurs. Please do not turn this into an ARRL bashing thread. I am an ARRL member and intend to remain so. I believe that most of the Directors and most Amateurs are thinking in terms of 3 kHz flat bandwidth and do not understand the 26 dB down requirement. What do we do? The ARRL is asking for comments and opinions from Amateurs about this proposal. You should write or e-mail your Division Director and let him know that you oppose the 3 kHz analog bandwidth part of the proposal. Also, you should write the League. If the Directors get a lackluster response in opposition to this proposal, it will probably be submitted to the FCC as is. If letters and e-mails in opposition barrage them, they should correct this situation. The league is governed by a group of Division Directors. League members elect these Directors. They are required to represent us, the members. This is our League. Frankly, I think that most of the Directors mean well by this but do not fully realize the problems that this will cause due to the minus 26 dB definition of bandwidth. It is our responsibility to tell them what we want. In my opinion, if there must be an established bandwidth at all, it should be 5 kHz per side band between 26 dB points. This would also be simpler than the current proposal. Here is a list of Directors and their e-mail: http://www.arrl.org/divisions The thing to NOT do is to get mad and quit the League. To do so is childish and hurts Amateur Radio. If Amateur Radio is to survive, we need the representation. The League has been extremely successful in many areas including preserving our frequencies in a very competitive world. They have made great strides to protect us from ignorant antenna ordinances, and the only hope in defending our interests against the big business BPL industry is strong representation provided by the ARRL. Without the League, BPL will eat us alive and we will find ourselves secondary to unlicensed services. If almost happened with Cable TV. The cable industry tried to hold us responsible whenever we interfered with transmissions through leaky lines. A strong effort on the part of the League prevented Cable TV from doing so. Beside your Division Director, send copies of your letters to bandwidth@arrl.org also send a copy to: President: Jim Haynie, W5JBP 3226 Newcastle Dr Dallas, TX 75220 w5jbp@arrl.org I would hope that we could resolve this problem now rather than having to oppose an ARRL sponsored petition before the FCC. Vy 73, Walter A. Breining, N9WB ________________________________________________________________________ ________________________________________________________________________ ------------------------------------------------------------------------ Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/ragchewersgroup/ <*> To unsubscribe from this group, send an email to: ragchewersgroup-unsubscribe@yahoogroups.com <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/ ------------------------------------------------------------------------