I see that others have told you that you can narrow the DSP and it will be just as good as long as there are no nearby signals greater than about S9+20.
Let me add that a huge improvement in copyability of weak CW can be gained by using the APF in current firmware. It has a bandwidth (I believe) of about 30 Hz at 6 dB points, and also provides a slight gain boost. It's easiest to select 1 Hz tuning steps (tab 'fine') when tuning with it on. I usually use a DSP bandwidth of 300-400 Hz and APF on when copying really, really weak signals. I know there are guys like W4ZV who have a DSP between their ears that does a better job with wider bandwidths, but not all of us have this ability! On 2/9/2011 12:07 AM, Edward R. Cole wrote: > Let me ask a filter question for a different situation. I am > interested in receiving very-weak CW and currently have the 2.8 KHz > and 400-Hz 8-pole filters. Will narrowing the DSP bw down to 200-Hz > work as well as using a 200-Hz filter? There are no strong stations > either nearby or on the band. > > BTW I am impressed with the 400-Hz filter on the K3 when compared to > the 400-Hz DSP on my FT-847 (no surprise). > I find trying to hear extremely weak-CW that narrowing down to 200, > 100 or even narrower makes the difference. > > I left a blank filter space on the main receive for adding a narrow > SSB filter at a later time. I also have the 13-KHz filter for > FM/AM. Sub-Rx has 2.8 and 13-KHz. > > > 73, Ed - KL7UW, WD2XSH/45 > ====================================== > BP40IQ 500 KHz - 10-GHz www.kl7uw.com > EME: 144-1.4kw*, 432-100w*, 1296-testing*, 3400-winter? > DUBUS Magazine USA Rep [email protected] > ====================================== > *temp not in service > ______________________________________________________________ > 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 -- Vic, K2VCO Fresno CA http://www.qsl.net/k2vco/ ______________________________________________________________ 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
