Decoders operate on the audio stream presented to them from the receiver. The decoding algorithms use the difference in audio level at each instant in time to make bit decisions. AGC reduces those differences and thus increases the bit error rate.
Of course, it is important to adjust the absolute audio levels so that the dynamic range of the signal(s) is placed within the dynamic range of the decoder. But, compressing the dynamic range, i.e., AGC, increases the error rate of the decoder. Ed W0YK _________________________________________________________________ -----Original Message----- From: Bill Frantz [mailto:fra...@pwpconsult.com] Sent: 07 March, 2017 13:05 To: e...@w0yk.com Cc: elecraft@mailman.qth.net Subject: RE: [Elecraft] [K3] AGC White Paper What I get using a relatively flat AGC is automation of my riding the RF gain control. I don't see how this kind of automation affects decoder performance. It should help performance as the decoder has a nearly constant level signal to work with. Please explain. Thanks - Bill AE6JV On 3/7/17 at 11:37 AM, e...@w0yk.com (Ed Muns) wrote: >Just the opposite. Most digital signal decoders work best with the least >AGC action possible, even AGC Off. AGC constrains decoder performance. > >Ed W0YK >_____________________________________________________________________ > >-----Original Message----- >From: Elecraft [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Bill >Frantz >... >Now to use SLP=15 for digital, where I want the AtoD to not >have to deal with a big range, while using something with more >dynamic range for voice/CW. ----------------------------------------------------------------------- Bill Frantz |Security, like correctness, is| Periwinkle (408)356-8506 |not an add-on feature. - Attr-| 16345 Englewood Ave www.pwpconsult.com |ibuted to Andrew Tanenbaum | Los Gatos, CA 95032 ______________________________________________________________ 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
