I designed analog and digital filters for processing flight test vibration measurements in the aerospace industry. I understand how cascaded filters work, and the function of a roofing filter versus the DSP filtering in the K3. I have owned and operated my K3 since mid 2008, and have turned the bandwidth knob a time or two during the past several years!
I prefer to keep my roofing filter bandwidth close to the DSP bandwidth, for maximum attenuation of close in signals. My experience running stations during Field Day is that callers are sometimes rusty on their CW skills and unfamiliar with the equipment they are using. A fairly wide bandwidth (500-600 Hz) is sometimes needed to capture these callers. Yes, turning the bandwidth knob will accomplish this, and should work in most cases. But some roofing filter will be in the chain. My preference is that it be 700 Hz rather than 2.1 or 2.7 KHz for the additional skirt selectivity and protection of the A/D from close in signals. I am not affiliated with Gary, other than being a satisfied customer. (I used his "Rework Eliminators" when I built my K2, and I have used the 700 Hz filter for several years now.). 73, Chuck NI0C ______________________________________________________________ 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
