I'm glad you beat me to this, Ray :) Wayne
> On Jun 19, 2021, at 11:50 AM, Ray <[email protected]> wrote: > > Did You Trying Transmitting in CW mode with the Mic disconnected ? > WA6VAB ray > > > From: Wayne Burdick > Sent: Saturday, June 19, 2021 11:41 AM > To: Tom Doligalski > Cc: Elecraft Reflector; John Harper > Subject: Re: [Elecraft] K4 observation > > > > On Jun 19, 2021, at 3:17 AM, Tom Doligalski <[email protected]> wrote: > > > > Actually, it could be a radio station. I haven’t listened long enough to > > ascertain… > > > > Frankly, I don’t care! The bigger problem is the rfi when I transmit. > > Which *will* be fixed. > > Wayne > > > > > Tom W4KX > > > > Sent from my iPad > > > >> On Jun 18, 2021, at 11:10 PM, w2xj <[email protected]> wrote: > >> > >> > >> Wayne > >> > >> I seriously doubt this is an RF issue. TV is all digital and has no > >> discrete audio carrier. TV RF interference would sound like white noise. > >> This sounds more like an audio ground loop of some sort. > >> > >> > >> > >> > >>> On June 18, 2021 10:33 PM Wayne Burdick <[email protected]> wrote: > >>> > >>> > >>> John, > >>> > >>> If the K4 is *off*, then there's no active circuitry involved. However, > >>> the headphone plug-insertion detect circuit may involve an IC downstream > >>> that could include a schottky diode junction -- a potential way a very > >>> strong signal could be rectified right at the radio end of the cable. > >>> We're looking at that. > >>> > >>> If the cable is not very well shielded, and the TV station is *very > >>> strong*, I can imagine modern physics just barely covering this > >>> situation. It would help if the headphone cable was about the length of > >>> an end-fed dipole at the station's frequency. > >>> > >>> As for the K4 chassis itself: It's very well sealed (far better than the > >>> K3/K3S). > >>> > >>> Wayne > >>> N6KR > >>> > >>> > >>> > >>>>> On Jun 18, 2021, at 3:36 PM, John Harper <[email protected]> wrote: > >>>> > >>>> https://www.youtube.com/watch?v=u1XRaNpgQDI > >>>> > >>>> John AE5X > >>>> https://ae5x.blogspot.com > >>>> > >>>>> Noticed that when the antenna are disconnected, and the K4 turned off, > >>>>> I hear a local TV station in the headphones… Never happened on the K3. > >>>> ______________________________________________________________ > >>> > >>> > >>> ______________________________________________________________ > >>> 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 > >>> Message delivered to [email protected] > >> ______________________________________________________________ > >> 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 > >> Message delivered to [email protected] > > ______________________________________________________________ > 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 > Message delivered to [email protected] ______________________________________________________________ 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 Message delivered to [email protected]
