Joe What you describe is not 'variable'. N4LQ Steve ----- Original Message ----- From: "Joe Subich, W4TV" <li...@subich.com> To: "Guy Olinger K2AV" <olin...@bellsouth.net> Cc: <elecraft@mailman.qth.net> Sent: Sunday, October 31, 2010 4:47 PM Subject: Re: [Elecraft] K3 APF Adjustable Q
> >>> What I have been trying to point out is that there is a general >>> benefit for a milder shape, that one MAY leave on all the time, >>> and tweak to tight as needed. > > If you want a "milder" shape, use Dual PB filter with a 400 - 500 Hz > background and 100 Hz foreground. That can certainly be left on > all the time and the APF switched on when needed ... at least once > all of the controls have been programmed. > > 73, > > ... Joe, W4TV > > > On 10/31/2010 12:03 PM, Guy Olinger K2AV wrote: >> I'd say for variable Q, the tightest setting should be just what is >> there now. So no one is losing anything. >> >> What I have been trying to point out is that there is a general >> benefit for a milder shape, that one MAY leave on all the time, and >> tweak to tight as needed. MP's EDSP, 450 Hz sidetone, NR=D, Contour= >> 11 oclock as an example of a mild contour that is really helpful. >> >> Being able to tune the APF tight setting around allows me to match the >> "tone" of the almost ring to the remembered tone of the weak station >> and have it come up when I hit it. >> >> If the choice is sharp or no APF and no APF tune, I have to RIT the >> station to sidetone. This has a couple of disadvantages. >> >> First, if running in a contest, and there are very loud stations up >> and down (aren't there always?), RIT up and down is going to let the >> co-channel guys in under the roofing filter and into pre-APF digital >> space. That can't be useful. Second, continuing to tune the station >> in becomes hard if the station stops or fades out because there is >> nothing to "calibrate" the completion of RIT twiddle other than >> hearing the tone from the station move to sidetone, and now it's >> stopped or faded. >> >> The presence of APF tune, or variable Q does not disadvantage anyone >> who doesn't need them, the same way all the really neat digital stuff >> does not disadvantage the straight CW operators. The current setting >> and shape of APF is definitely the right max Q setting, and does very >> well for me. >> >> I just want a mild Q setting to imitate the shape I had with the MP >> all those years. Those who hear it will get it, just like those that >> hear the sharp APF for the first time and try it, get it. I think a >> lot of people will leave a mild Q on ALL THE TIME for general >> operating. It lowers the level of the stuff up and down a little >> without any ringing, but still allows one to hear up and down for off >> frequency callers. For me it's an EASIER listen for hours on end. >> >> 73, Guy. >> >> On Sun, Oct 31, 2010 at 10:47 AM, Steve Ellington<n...@carolina.rr.com> >> wrote: >>> If the caller is off frequency I would just use RIT to center him in my >>> passband as usual and let APF do it's thing. >>> Having used outboard APFs for years, the ability to adjust it's >>> selectivity >>> is very important. If the band is quiet and the signal is very weak, I >>> would >>> adjust the APF nearly to the point of oscillation then back it off a >>> tad. If >>> the signal is weak but there is a lot of QRN, I would back off the >>> selectivity a bit further but still take advantage of some extra peaking >>> capability. >>> >>> N4LQ >>> Steve >>> >>> ----- Original Message ----- >>> From: "Joe Subich, W4TV"<li...@subich.com> >>> To:<elecraft@mailman.qth.net> >>> Sent: Sunday, October 31, 2010 10:27 AM >>> Subject: Re: [Elecraft] K3 APF Adjustable Q >>> >>> >>>> >>>>>> however the fixed Q has a bit of ring and at times I would like to >>>>>> back it off (widen) it just a tad. >>>> >>>> This is the same mistake Yaesu made in the FT-1000D; de-Qing the >>>> original APF made it useless in later radios. This is the very >>>> reason not to add adjustable Q or reduce the Q of the APF currently >>>> in field test. If you want a less aggressive filter that is centered >>>> on the sidetone, use Dual PB ... that's exactly what it is designed >>>> to do (and it does a very good job when used as designed). >>>> >>>> Adjustable center frequency is very important ... particularly when >>>> PB CTRL is set for Shift=.05 (to allow LO-CUT-HI to function) as >>>> the 50 Hz increments too course to tune APF using the VFO. The user >>>> also needs the ability to adjust the peak independently in order to >>>> peak up an off frequency caller and not "chase them up the band." >>>> >>>> 73, >>>> >>>> ... Joe, W4TV >>>> >>>> >>>> On 10/31/2010 8:58 AM, Steve Ellington wrote: >>>>> If I had a choice between variable center frequency and adjustable Q, >>>>> I >>>>> would choose adjustable Q. >>>>> >>>>> My logic is: The center frequency automatically follows the sidetone >>>>> frequency so I have no need to adjust it however the fixed Q has a bit >>>>> of >>>>> ring and at times I would like to back it off (widen) it just a tad. >>>>> >>>>> Otherwise it's a HUGE improvement, sounds great and I wish to thank >>>>> those >>>>> who made it possible. >>>>> >>>>> 73 >>>>> N4LQ >>>>> Steve >>>>> >>>>> ______________________________________________________________ >>>>> 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 >>>>> >>>> ______________________________________________________________ >>>> 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 >>> >>> ______________________________________________________________ >>> 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 >>> >> > ______________________________________________________________ > 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 ______________________________________________________________ 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
