The hardware (IF in the NB LEVEL display) blanker is analog, and works the same as blankers in analog receivers for decades. But it takes high impulse very short spikes to drive it. An analog blanker will always cause some degree of "distortion", description of said "distortion" always particular to the hearer. Not just K3, any classic analog blanker. The circuit is modulating the IF with what amounts to a square wave pulse. Noteworthy in use of these is splatter from other loud signals in the IF stage which has the blanker.
>From time to time on the lower bands, I have my hide-and-seek 13kV power line buzz. The IF blanker works well on this for me as long as it's not a contest. I drop back to the DSP blanking in a contest, but without all the loud signals to splatter the IF blanker, the IF is a tad better. On the other hand, I have this AC related growl/buzz on 6 meters which the IF blanker won't touch at all. DSP blanking t2-7 or t3-7 gets it nicely. The DSP blanker is the future. It's code. It can be worked on, improved, and have new ideas added to it. Oh, and one other thing, running the RF gain wide open on lowbands with PRE on, or not using ATT when you should, is the enemy of the blankers. Engaging the ADC defense hardware AGC by smash-mouthing RF gain/PRE/ATT settings mushes blanker effectiveness. 73, Guy. On Sun, Jun 13, 2010 at 10:15 PM, juergen <[email protected]> wrote: > Hi Toby > > Frankly the hardware noise blanker on the K3 is mostly useless. > > I dont really dont even know if its "analog" in nature. I have compared it to > many other analog blankers on other radios, if it does work its barely > perceptible. > > I must have a faulty analog blanker. The way people speak about how well it > works i just dont see in practice. I have 2 k3's and have used my clubs K3's > and they are all the same. All i seem to hear is distortion and no blanking > effect. > > > The DSP noise blanker on the K3 is a different story. On any of the number 7 > settings it will take care of most power line noise. I find that you > really need to use the 7 setting even for mild power line noise. On true > analog noise blankers you could take out mild power line noise without > aggressive settings which just cause distortion. The K3's DSp noise blanker > is impressive even with all the distortion, so yes it does "work" > > If you do have a radio from the past that works in your location I would > suggest you keep it. That is what I have done, I have radios here that I use > on the low bands that beat the K3's DSP blanker and they just conventional > analog blankers. The big advantage is that I can use these blankers on low > settings and still have a "decent" receiver without distortion. > > > Noise blankers on radios have always been luck of the draw. I know of > several people who have changed radios for nothing more than good noise > blanker performance. These days operating anywhere in big cities you really > need a decent noise blanker. > > > John > > > --- On Sun, 6/13/10, Toby Pennington <[email protected]> wrote: > >> From: Toby Pennington <[email protected]> >> Subject: [Elecraft] Hardware Noise Blanker on the K3 >> To: [email protected] >> Date: Sunday, June 13, 2010, 6:41 PM >> Someone with power line >> noise.......does the hardware noise blanker work very well >> on s9 power line noise. IF so, is the SSB signal >> distorted ? DSP blankers work to some extent but >> distort the audio. >> >> Toby W4CAK >> ______________________________________________________________ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:[email protected] >> >> 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:[email protected] > > 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:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
