Diddn't proof read enoough, meant voltage transformer. Brian D <gro...@planet3.freeuk.co.uk> wrote:
> I have had similar problems with swr trips on my KPA500, only after > several transmissions on some bands. By a process of elimination it was > traced to a toroidal voltage transformer > heating up in an external coupler. It came on > suddenly after about 5 minutes of transmissions, and came good after a few > minutes to cool. Replacing the toroid with a larger one cured the problem. > > > > "Ron D'Eau Claire" <r...@cobi.biz> wrote: > > > Hi Dave: I thought you said it happened after you sent CQ+Call a few > > times. When a core heats to its Curie temp, the inductance change > > happens "instantly". You are right - if it happens instantly when you > > hit the key it is not heating. Something is breaking down. > > > > 73, Ron AC7AC > > > > -----Original Message----- From: Elecraft > > [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Dave Cole Sent: > > Saturday, May 13, 2017 10:39 AM To: elecraft@mailman.qth.net Subject: > > Re: [Elecraft] Strange SWR change on 20 at > > > > I added the SWR meter... My actual SWR jumps instantly up about1 SWR > > unit... I believe it is a bad connection on the Challenger where the > > main antenna connects to the 20 meter tuning stub... > > > > Just sort of surprised me to see a second person with the exact same > > issue is all... SWR change is instant, so it is not heating... Happens > > at 30 watts, or 1 KW... Time for a rebuild. > > > > 73s and thanks, Dave NK7Z http://www.nk7z.net > > > > On 05/13/2017 10:07 AM, Dave Cole wrote: > > > Hmmm... I am having the exact same issue... My SWR changes after a > > > few transmissions, then returns... Up until now, I have been > > > suspecting my antenna... Time to add an external SWR bridge between > > > the tuner and antenna as a permanent thing... > > > > > > 73s and thanks, Dave NK7Z http://www.nk7z.net > > > > > > On 05/13/2017 09:07 AM, Terry Brown wrote: > > > > I recently started using my horizontal loop that is about a full > > > > wavelength on 80, for 20 meters. I took down my yagi as we are > > > > moving; drat! My Horizontal Loop is at 40 ft. height and fed with > > > > 450 window line into a 4:1 voltage balun with about 15 ft. of coax > > > > to rig. > > >> > > >> > > >> > > > > I am running 100 watts through my KXPA100. I tune a frequency in > > > > the CW portion of 20 to about 1.2 :1 and start sending CQ. After > > > > about 3 to 4 3x3 CQ's,, the SWR goes off the charts and power drops > > > > to zero. I can retune the antenna and the process repeats itself. > > > > 20 meters is the only band affected. > > >> > > >> > > >> > > > > I am wondering if I am having RF problems in that part of the 20 > > > > meter bands This only occurs on 20 meters. The Amp is grounded, but > > > > the KX3 is not bonded to the Amp. > > >> > > >> > > >> > > > > I would appreciate any advice. > > >> > > >> > > >> > > > > Thanks and 73's, > > >> > > >> > > >> > > > > Terry de N7TB > > >> > > > > ______________________________________________________________ > > > > 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 > > > > d...@nk7z.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 > > > d...@nk7z.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 r...@cobi.biz > > > > ______________________________________________________________ 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 > > gro...@planet3.freeuk.co.uk > > > > > > -- Brian Duffell Yarm England ______________________________________________________________ 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
