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 > >
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