What is the best way of determining the gain setting? Seem to recall an app for this.
David Wilburn NM4M Sent from my Verizon Wireless BlackBerry -----Original Message----- From: Brett Howard <br...@livecomputers.com> Date: Sat, 15 Aug 2009 15:51:46 To: Merv Schweigert<k...@flex.com> Cc: <Elecraft@mailman.qth.net> Subject: Re: [Elecraft] K3 new V3.25 NR not so good for CW week signal Not saying I'd do it. (and I'm not with the 8 filters I have in my radio) but one can if thats what they wish to do. ~Brett On Sat, 2009-08-15 at 12:42 -1000, Merv Schweigert wrote: > Not really, if you read the recommendations for the filters you will > notice > that caution is warranted for setting the gain higher than > recommended, > for IMD prevention if I remember correct. Kind of like the Inrad > roofing > filters, in some cases the gain is set to high and causes more IMD > than > without the filter. > Some Inrad roofers for the FT-1000D had too much gain and the radio > was worse with them installed than without. W8JI had some > measurements > on those issues. > Merv KH7C > > This is sorta already there if you have multiple roofing filters. You > > can define the gain that is added when each filter kicks in. > > > > > > On Sat, 2009-08-15 at 13:50 -0600, William Carver wrote: > > > > > I've noticed in homebrew receivers as the bandwidth narrowed, shedding > > > noise and QRM I preferred the gain to go up, increaseing the in-passband > > > signal amplitude. I always attributed it to formative years with a > > > Heathkit Q multiplier. It may be an effect similar to AGC with > > > adjustable flatness (May 1996 analog circuit, in DSP of K3). I found I > > > preferred to have strong signals sound louder rather than perfectly > > > flat. Prolly a psycho-acoustic explanation (or maybe just get my head > > > examined?). > > > > > > In firmware one could increase the audio gain by an adjustable amount as > > > the IF bandwidth was decreased, with an operator-settable scaling > > > number. Say 0 = gain independent of bandwidth, to 100 = gain multiplied > > > by K * (2800/DSP bandwidth). Very similar to the AGC rise scaling. That > > > sounds good to me. > > > > > > > > > > > > ______________________________________________________________ > > > 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 > > > > > > > ______________________________________________________________ > > 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 > > > > > ______________________________________________________________ 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 ______________________________________________________________ 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
