I agree with this assessment and when I get my rig back plan on upping my 250 filter to kick in at 350. But I had 4dB of gain on the 250 and it still seemed like things got a lot quieter when switching to the 250. I'd have to measure and see if I had the actual same level there (and I can do that now that I have the XG2) :).... But I did have 4dB thrown in for good measure! :) I found myself using the 250 all the time for rag chewing... But I use 250 on my K1 for its lowest filter position too..
I tend to generally like things pretty quiet. I use 850 for scanning the band (as that is as wide as the K1 can go). I use 500 to 550 for calling CQ if they're further away than that then I guess I don't get to hear them... And then I crank it down to 200 to 250 when I'm talking with a guy. It not only ensures that I'm pretty close to zero beat with him but also makes things quieter and gets rid of a lot of the electrical hash I have in my area. The K1's noise blanker doesn't hold a candle to the noise in my area but the K3 was doing a pretty fantastic job! On Tue, 2008-07-08 at 08:02 -0700, Dick Dievendorff wrote: > A couple of related points, which may not be new news to anyone: > > You can set the K3's filter bandwidth configuration to cause the roofing > filter to switch at points other than the bandwidth printed on the filter. > Maybe you would like your (nominally) 500 Hz filter to switch in at 450 or > 550 Hz. My 8-pole 250 Hz filter is a bit broader than 250 Hz, and I've set > it to switch at 300 Hz. > > You can also turn off a filter (set its bandwidth to zero temporarily) to > evaluate whether a change you're hearing is due to the roofing filter or the > change in bandwidth provided by the DSP. > > And you should attempt to adjust the filter gain compensation so that there > is no change in the volume of the note you're tuned to. Rene, who guides > the assembly of K3s built by Elecraft, told me that he uses a voltmeter on > the speaker terminals when adjusting the gain compensation and can get > usually get within a half decibel. > > I notice a definite qualitative change as the narrower filters switch in. It > sounds quieter, and it seems like the volume is being turned down. I think > I'm responding to the reduced low and high frequency components that are > supposed to be cut off. The DSP-related changes seem more gradual. > > Dick, K6KR > > > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Darwin, Keith > Sent: Tuesday, July 08, 2008 7:43 AM > To: [email protected] > Subject: RE: Re: [Elecraft] Hearing the effect of narrower roofing filter > > Not sure, David, if your Q was to me or to Hank. I can only answer for > me. > > When I adjust the filter width knob, I'm most definitely hearing the > combined effect of the DSP bandwidth reduction and the change in roofing > filters. But, since I can change DSP without changing the roofing > filter (by stepping from 1500 Hz down to 550 Hz) I can get a good feel > for how the DSP filter sounds. Then, stepping to 500 Hz, I can see the > combined effect of one more DSP step plus the insertion of the 500 Hz > roofing filter. The observed big change from 550 Hz to 500 Hz is > *mostly* due to the roofing filter. > > - Keith N1AS - > - K3 711 - > > ----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of > [EMAIL PROTECTED] > > Fine observations when you change the filter setting knob, but what > makes you think you are hearing the effect of the roofing filter and not > the dsp filter? > > David > G3UNA > > _______________________________________________ > Elecraft mailing list > Post to: [email protected] > You must be a subscriber to post to the list. > Subscriber Info (Addr. Change, sub, unsub etc.): > http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/subscribers.htm > Elecraft web page: http://www.elecraft.com > > No virus found in this incoming message. > Checked by AVG - http://www.avg.com > Version: 8.0.138 / Virus Database: 270.4.6/1540 - Release Date: 7/8/2008 > 6:33 AM > > > > No virus found in this incoming message. > Checked by AVG - http://www.avg.com > Version: 8.0.138 / Virus Database: 270.4.6/1540 - Release Date: 7/8/2008 > 6:33 AM > > _______________________________________________ > Elecraft mailing list > Post to: [email protected] > You must be a subscriber to post to the list. > Subscriber Info (Addr. Change, sub, unsub etc.): > http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/subscribers.htm > Elecraft web page: http://www.elecraft.com _______________________________________________ Elecraft mailing list Post to: [email protected] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
