I’ve done all that. On some voices, distortion is minimal. On others, it is serious.
Dave Hachadorian, K6LL Yuma, AZ From: Johnny Siu Sent: Sunday, March 30, 2014 5:29 PM To: Dave Hachadorian ; Reflector Elecraft Subject: K3 in WPX SSB with 2.7 roofer Hello Dave, I did have the same experience with 1.8Khz filter in the past. However, upon the guidance of my contest elmer, I played around the IF shift. By moving the centre position of the IF passband, you will find a sweet spot where you can hear the speech with minimal degrade but excellent selectivity. 73 Johnny VR2XMC 寄件人︰ Dave Hachadorian <k6ll.d...@gmail.com> 收件人︰ Reflector Elecraft <elecraft@mailman.qth.net> 傳送日期︰ 2014年03月31日 (週一) 4:30 AM 主題︰ [Elecraft] K3 in WPX SSB with 2.7 roofer I was in the WPX SSB contest this weekend, and wanted to try using just the 2.7 roofing filter, using only DSP to narrow the response below that. I previously have had the feeling that the 1.8 roofer was degrading speech intelligibility. The WPX is a QRM-fest of the first order. Everybody can work everybody, so the whole world is doing their own thing all the time. 15 meters was particularly bad, with almost nobody having a clear channel. Using only the 2.7 filter, I never experienced a case of adjacent-signal AGC pumping, or any other negative issue during the contest. I think if an SSB signal is so close to you that it is pumping your agc through the 2.7 filter, the frequency is hopelessly splattered anyway, and you'd best be moving on. I did narrow the DSP down by using HI CUT, and usually ran it at LOW=0.15 and HIGH=2.25. I could be persuaded to part with my pair of 1.8 filters, if someone is interested in them. Dave Hachadorian, K6LL Yuma, AZ ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net/ Please help support this email list: http://www.qsl.net/donate.html Message delivered to vr2...@yahoo.com.hk ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
