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 <w...@mac.com> 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 <w...@w2xj.net> 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 <n...@elecraft.com> 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 <johna...@gmail.com> 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:Elecraft@mailman.qth.net >>> >>> This list hosted by: http://www.qsl.net >>> Please help support this email list: http://www.qsl.net/donate.html >>> Message delivered to w...@w2xj.net >> ______________________________________________________________ >> 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 >> Message delivered to w...@mac.com ______________________________________________________________ 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 Message delivered to wa6...@gmail.com ______________________________________________________________ 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 Message delivered to arch...@mail-archive.com