I am pretty sure the DSP filter is effective only if it is narrower than the roofing filter. In your setup the DSP filter is pretty much turned off. Please, don't forget, the crystal filters in K3 are ROOFING filters, they are protecting next IF stages and the DSP from strong near by signals, improving dynamic range . The main filtering is done in DSP. There is white paper on the matter somewhere on Elecraft web site (by Eric S).
73, Igor, N1YX ----- Original Message ----- From: "Dave Hachadorian" <[email protected]> To: "Elecraft Reflector" <[email protected]> Sent: Tuesday, March 27, 2012 12:52:51 PM Subject: Re: [Elecraft] K3 Filter questions I used the 1.8 for the entire WPX SSB contest, with a DSP width of 2.1 KHz. It sounded great. I never messed with any of the settings for the entire contest. To get this combination of DSP=2.1 and crystal=1.8, one has to install the 1.8 filter as if it were a 2.1, so it switches in at DSP=2.1. This installation setup is most easily done using the K3 Utility. In practice, normalize, then use high cut until the filter switches in. To me, the audio sounds best using that technique. WPX SSB is traditionally the worst-case QRM-fest, and the 1.8 filter was just the ticket for dealing with it. Dave Hachadorian, K6LL Yuma, Arizona >From experience, I had both the 2.1 and 1.8 fitted and by >judicious use of the Hi Cut/Lo Cut adjustment I find the 1.8 far better in practice. ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] 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:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
