Multiple peaks? At what bandwidths? My K2 give nice flat filter shapes at bandwidths 1000 Hz and narrower. At SSB bandwidths, the filter passband has several or more very large peaks and has a gentle roll off in either lows (USB) or highs (LSB). Even at widths of 1.6 KHz the passband shows a couple of big peaks.
In contrast my IC-735 shows a nice flat passband with no slope to it (thus proving the issue is not my PC sound card or the way I ran spectrogram). I did some screen shots and sent them to Elecraft support to see if it was a problem. No it's not. The Xtal filter was optimized for variable bandwidth over CW bandwidths and doesn't work as well at SSB widths. Apparently the fixed-width filter in the SSB adapter does not have this issue. Your post sounds like your rig is not "right". My rig has the new generation matched Xtal filters and I put in the 2nd set of grounding straps (per the instructions in the KSB2 documentation IIRC). Oh, and with spectrogram, I got much better results if I let it filter / average over 3 seconds or so. That really suppressed the noise and showed the filter shape more accurately. - Keith KD1E - - K2 5411 - -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED] Sent: Tuesday, May 23, 2006 9:38 AM To: [email protected] Subject: [Elecraft] Filters The filters in my K2 have always been a little weird. Tuning around, the signal would always peak at the wrong point and then drop when it's at the correct sidetone frequency. I lived with it for a while. I finally took some initiative and tried it out with spectrogram and using the Elecraft noise generator. My findings were a bit suprising. The filter shape has multiple peaks and is not uniform at all.. compared to a few others I have seen. I compared it to another friends K2 and it was confirmed - my filter shape is funky. What should I do? Do I need to buy new crystals? Is something out of whack? Thanks, James Kern KB2FCV _______________________________________________ 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
