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I have three 8 pole filters installed, 2.8, 1.8, and .4 kHz. As I
rotate the WIDTH knob, the filters switch in and out at their transition frequencies (as they should). But when that switch occurs, the background noise pitch frequency seems to jump to a different SHIFT frequency setting. In other words, the transition between filters is not smooth. I am wondering if all K3's with 8 pole filters do the same thing as mine? My filter offsets are all set to zero, as that is what I am told the 8 pole filters offsets should be. _______________________________________________ Elecraft mailing list Post to: [hidden email] 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 |
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I suspect that the filter gain rather than the width is the major cause
of that behavior. Try working with the FLx GN setting in the CONFIG menu to see if you can obtain a smoother transition. You could expect the widest filter to have the smallest loss, so start with the transition between FL1 and FL2 and when that seems right, move on to the FL2 and FL2 transition, etc. The easiest way to do this is with a broadband noise generator (such as the Elecraft NGen) so you have a constant input to the K3 and it would be easy to evaluate the audio level using Spectrogram or some other audio spectrum analyzer, although a AC DMM connected across the speaker would give decent results. Once you have the filter gains equalized, you can easily change the filter offsets if necessary. While the 8 pole filter offsets are close to zero, it is not practical to expect that they are all exactly zero. 73, Don W3FPR W5UN wrote: > I have three 8 pole filters installed, 2.8, 1.8, and .4 kHz. As I > rotate the WIDTH knob, the filters switch in and out at their > transition frequencies (as they should). But when that switch occurs, > the background noise pitch frequency seems to jump to a different > SHIFT frequency setting. In other words, the transition between > filters is not smooth. > > I am wondering if all K3's with 8 pole filters do the same thing as mine? > > My filter offsets are all set to zero, as that is what I am told the > 8 pole filters offsets should be. > > Elecraft mailing list Post to: [hidden email] 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 |
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In reply to this post by Dave-W5UN
Hi, I find that shift has to be reduced progressively as width is reduced on SSB eg. 2.7KHz width *1.5KHz shift 2.1KHz *1.25KHz shift As I decrease the WIDTH past my 2.1KHz roofing filter with DSP, I constantly adjust SHIFT downwards to achieve normal sounding audio eg. 1.8KHz 1.1KHz shift I asked Lyle about it and he said that for SSB, LO and HIGH CUT should be used instead of WIDTH for SSB. WIDTH is meant for narrow bandwidth modes i.e. CW. Personally I find LO and HIGH cut arkward to use, especially when you have optional roofing filters installed. This is because the primary function of NORM is overloaded to automatically select the 2.7KHz roofing filter???. The secondary function of NORM (I/II) means you can have a some defaults, but try remembering what's behind them in the middle of a contest (if you get enough time to select them). It would be nice if the primary function of NORM just normalised the current filter width around the current shift value. Doug GM0ELP |
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Doug, GM0ELP wrote:
> Personally I find LO and HIGH cut arkward to use, especially when you have > optional roofing filters installed. This is because the primary function > of > NORM is overloaded to automatically select the 2.7KHz roofing filter???. > The > secondary function of NORM (I/II) means you can have a some defaults, but > try remembering what's behind them in the middle of a contest (if you get > enough time to select them). > > It would be nice if the primary function of NORM just normalised the > current > filter width around the current shift value. When using narrow (250 Hz 8-pole XTAL) filters in the two receivers I find the shift is sensitive to touch and adjust. It would be good to have smaller increments than the present. I usually have the CW pitch set to 520 Hz. Cannot remember it was this sensitive before the latest F/W upgrade, was it? any one else noticed this? 73 Len SM7BIC _______________________________________________ Elecraft mailing list Post to: [hidden email] 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 |
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In reply to this post by GM0ELP
Doug,
I always use the HiCut/LoCut for SSB and just forget about the NORM settings. The center frequency will be automatically set and it is quick to turn the HI knob just enough to reduce interference - the roofing filters will switch in automatically as required to support the DSP bandwidth. If you listen to a SSB signal and try using the LO and HI CUT knobs, you should observe that you can cut a lot at the high end, but not much can be cut on the low end without loosing intelligibility. I agree it is a pain to maintain intelligibility for a voice signal when using the WIDTH and SHIFT controls - every time the width is changed, the shift must be adjusted to maintain a usable speech response - it is a requirement, just like you indicated. If you look at the frequency content of a human voice, you will find that there must always be energy in the 300 to 500 Hz range to maintain intelligibility. If you have a 2.2 kHz filter set that extends from 300 Hz to 2500 Hz (filter center 1.4), and you narrow that using the width control to 1.8 kHz, the filer center will stay at 1.4 kHz, and the filter will span from 500 Hz to 2.3 kHz - the important portion of the signal at 300 to 500 Hz will be gone, and the passband must be re-centered at 1.2 kHz to gain it back. I believe it is much easier to set the LoCut somewhere in the 200 to 350 Hz range (let's assume it is set at 300 Hz). For a 2.2 kHz filter width, set the HiCut to 2.5 kHz. If you then move the HiCut down to 2.1 kHz, the filter width is now 1.8 kHz and intelligibility is maintained - if you have the 1.8 kHz roofing filter installed, it should be switched in automatically when the width is reduced to 1.8 kHz either by using the HiCut or the WIDTH control. One does not have to do the addition and subtraction to determine the filter width at all - just change the HI CUT knob until the QRM is reduced sufficiently - move LO CUT a little if that is necessary too, but do it while listening to the signal, you will know when the desired signal becomes unintelligible. Try it - if your narrow filters do not switch in automatically when using only the HiCut, there is something wrong. Let the DSP do the math for you, it is much faster at that task than either of us are. 73, Don W3FPR GM0ELP wrote: > Hi, > I find that shift has to be reduced progressively as width is reduced on SSB > eg. > > 2.7KHz width *1.5KHz shift > 2.1KHz *1.25KHz shift > > As I decrease the WIDTH past my 2.1KHz roofing filter with DSP, I constantly > adjust SHIFT downwards to achieve normal sounding audio eg. > > 1.8KHz 1.1KHz shift > > I asked Lyle about it and he said that for SSB, LO and HIGH CUT should be > used instead of WIDTH for SSB. WIDTH is meant for narrow bandwidth modes > i.e. CW. > > Personally I find LO and HIGH cut arkward to use, especially when you have > optional roofing filters installed. This is because the primary function of > NORM is overloaded to automatically select the 2.7KHz roofing filter???. The > secondary function of NORM (I/II) means you can have a some defaults, but > try remembering what's behind them in the middle of a contest (if you get > enough time to select them). > > It would be nice if the primary function of NORM just normalised the current > filter width around the current shift value. > > Doug GM0ELP > > > Elecraft mailing list Post to: [hidden email] 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 |
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For ssb contests, I've got Norm 1 set for BW=1.8, FC=1.1
I leave the controls in the shift/width mode and make minor tweaks on the shift control to maximize intelligibility with different voice characteristics. I don't touch the width control during the contest. There are a lot of different ways to operate this radio. Dave Hachadorian, K6LL Yuma, AZ _______________________________________________ Elecraft mailing list Post to: [hidden email] 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 |
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In reply to this post by Lennart Michaëlsson
I haven't found it any more sensitive. The granularity is 50hz and I believe
that 10hz would work much better for CW. Because of this, I really never use shift as I have in other rigs. 73, Gary W7TEA When using narrow (250 Hz 8-pole XTAL) filters in the two receivers I find the shift is sensitive to touch and adjust. It would be good to have smaller increments than the present. I usually have the CW pitch set to 520 Hz. Cannot remember it was this sensitive before the latest F/W upgrade, was it? any one else noticed this? 73 Len SM7BIC _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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
73,
Gary W7TEA K3 #1001, #5763 |
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W7TEA wrote:
> The granularity is 50hz and I believe that 10hz would work much better > for CW. We're planning to improve SHIFT granularity (etc.) in a future firmware release. 73, Wayne N6KR --- http://www.elecraft.com _______________________________________________ Elecraft mailing list Post to: [hidden email] 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 |
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In reply to this post by Don Wilhelm-4
Hi Don,
Thanks for info, I have tried it and have let it do the math as you suggested. The problem comes when you are operating in a contest and QRM both above and below is constantly changing. Having both LO and HI CUT to tweek during RX periods ONLY is just too restrictive and no-one I have spoken to in the above situation uses LO and HIGH CUT for this reason. If the primary function of NORM didn't change the roofing filter as well or adjustment were allowed during tx then the situation would be better. Cancelling any redundant settings of LO and HIGH CUT in one button push would be more easily accomplished and would become useable for contests. Everyone I have spoken to are working around these firmware quirks by using the harder to get at secondary feature of the NORM button to select a known SHIFT and WIDTH setting during RX whilst simultaneously trying to type calls. It's a hassle and detracts from the operating enjoyment of the K3 and is why I mentioned it. Doug GM0ELP
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Hi Doug and Don,
This is one aspect of the K3 on SSB that I think can be improved. I agree that in a contest there is just not enough time to tweak the SSB filters for maximum intelligibility. HI CUT without an accompanying LO CUT does not work very well to improve intelligability. It would help if the WIDTH control would move the centre frequency down/up by a fraction of the bandwidth change (approx. 25Hz per KHz). I suggested some time ago that the XFIL button was not much use on SSB. Personal choice SSB filter settings could be saved and be recalled by repeated pressing of the XFIL button. For general listening I use macros and the K3 Utility to recall any number of filter settings. I would rather not go to the computer to accomplish this. My fingers just could not control those little knobs for filter adjustment (poor eyesight and insensitive fingers) so I fitted 2 larger knobs (3/4 in dia and 7/8 in long). They are a bit big but I no longer nudge the VFO knob. I would also have preferred a positive detent on the filter encoders. 73 Tony Fegan VE3QF K3 #137 GM0ELP wrote: > Hi Don, > Thanks for info, I have tried it and have let it do the math as you > suggested. The problem comes when you are operating in a contest and QRM > both above and below is constantly changing. Having both LO and HI CUT to > tweek during RX periods ONLY is just too restrictive and no-one I have > spoken to in the above situation uses LO and HIGH CUT for this reason. If > the primary function of NORM didn't change the roofing filter as well or > adjustment were allowed during tx then the situation would be better. > Cancelling any redundant settings of LO and HIGH CUT in one button push > would be more easily accomplished and would become useable for contests. > Everyone I have spoken to are working around these firmware quirks by using > the harder to get at secondary feature of the NORM button to select a known > SHIFT and WIDTH setting during RX whilst simultaneously trying to type > calls. It's a hassle and detracts from the operating enjoyment of the K3 and > is why I mentioned it. > > Doug GM0ELP > > > Don Wilhelm-4 wrote: >> Doug, >> >> I always use the HiCut/LoCut for SSB and just forget about the NORM >> settings. >> The center frequency will be automatically set and it is quick to turn >> the HI knob just enough to reduce interference - the roofing filters >> will switch in automatically as required to support the DSP bandwidth. >> >> > _______________________________________________ Elecraft mailing list Post to: [hidden email] 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 |
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On Jan 28, 2009, at 1:32 PM, Tony Fegan VE3QF wrote: > I suggested some time ago that the XFIL button was not much use on SSB. > Personal choice SSB filter settings could be saved and be recalled by > repeated pressing of the XFIL button. You can use the I/II "floating" presets if you have two crystal filter/DSP filter setups you prefer during contests. They were intended for exactly this purpose -- quickly adjusting the passband to accommodate changing conditions. Just hold I/II to switch between them (adjust DSP controls as required for each one). These settings are saved per-mode. 73, Wayne N6KR --- http://www.elecraft.com _______________________________________________ Elecraft mailing list Post to: [hidden email] 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 |
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This is what I do on SSB. Works great here.
73, Bill K9YEQ K2 #35; KX1 #35; K3 #1744; mini mods On Jan 28, 2009, at 1:32 PM, Tony Fegan VE3QF wrote: > I suggested some time ago that the XFIL button was not much use on SSB. > Personal choice SSB filter settings could be saved and be recalled by > repeated pressing of the XFIL button. .............. Just hold I/II to switch between them (adjust DSP controls as required for each one). These settings are saved per-mode. 73, Wayne N6KR _______________________________________________ Elecraft mailing list Post to: [hidden email] 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 |
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I note that I can use NORM during TX but not NORM I/II, is this in the fix list?
Doug GM0ELP
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On Jan 31, 2009, at 4:05 AM, GM0ELP wrote: > > I note that I can use NORM during TX but not NORM I/II, is this in the > fix > list? Yes. Wayne N6KR --- http://www.elecraft.com ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
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