Sorry for the late response.. I had the exact problem several weeks ago. Every time I removed the batteries the problem would be resolved.. The problem was ultimately me being a dumb ass.. I had purchased a nice blue tooth speaker that perfectly sat on top of the KX3, however it kept sliding off. My solution was to glue a small round magnet on the front corners on the KX3 top. I also glued the same small magnet on the bottom of the radio. Well guess what, I knew better but didn't even think about magnetic shielding of the inductors in the ATU. While testing everything was fine, when I was convinced everything was ok I would place the radio back in it's operating position everything was still ok even with speaker on top, as long as I was on 20 meters, as soon as I went to 40 which could be a couple of days later.. the radio again went to 25.4:1
One magnet was not enough to do it, but when both magnets were on the top right hand corner, it was all over for the ATU.. makes 100% sense now that I know what was happening... Regards.. Fred Fred Moore email: [email protected] [email protected] phone: 321-217-8699 On 4/19/17 11:55 PM, nate t wrote: > Hi all, > > I opened up the KX3 and pulled the ATU, everything seemed to be in order and > the LPF was in the correct position. > > I put the original batteries back in to keep the testing the same as > previously. They were a bit lower than I had previously thought, read 9V > (alkaline). I put up a 20m dipole and tested it, 20m tuned up right away and > I let it run for a bit. I then switched down to 40m and it tuned up right > away to a 1.0:1. After switching back and forth between 40/30/20 a few times, > I noticed that the relays seemed to be switching a bit slower than normal, > and that the tuning power was going down to 2.0W instead of the normal 3.0W. > > Went to 40m again, and it started landing on the 25.4:1 SWR every try. Pulled > up the battery monitor on the display, and while it was running the tuning > process, the voltage was dropping down to 7.9V, and it'd stick at 25.4:1. > Switched over to external power and it would properly tune 40m again on the > 20m dipole without issue. > > The dummy load I ordered arrived today as well, and using new batteries, it > will tune 1:0.1 on all bands. > > I'm going to chalk this up to being a low voltage situation, and hopefully it > doesn't return! > > I appreciate everyone's suggestions. > > 73 > > >> On Apr 17, 2017, at 11:35 AM, Walter Underwood <[email protected]> wrote: >> >> 25.4:1 SWR is what the KX3 reads for a short or an open, if I remember >> correctly. >> >> Agreed, open it up, make sure everything is tight, include the ribbon cable. >> >> wunder >> K6WRU >> Walter Underwood >> CM87wj >> http://observer.wunderwood.org/ (my blog) >> >>> On Apr 17, 2017, at 11:20 AM, Don Wilhelm <[email protected]> wrote: >>> >>> Nate, >>> >>> Since the problem is intermittent, I would not suspect a problem with an >>> active component. >>> >>> You might want to remove the bottom cover and check to be certain the >>> hardware on the BNC jack is tight and the LPF on the BNC connector is >>> properly positioned. You may have to lift the KXAT3 to check - see Figure >>> 43 of the KX3 Kit Assembly Manual. >>> >>> 73, >>> Don W3FPR >>> >>> On 4/16/2017 4:55 AM, nate t wrote: >>>> Hi, >>>> I was working with my KX3 earlier today, RX only, using an endfed, while >>>> running on batteries, RXing WSPR and PSK31. >>>> After running for a bit, the ATU seemed to stop working. Attempting to >>>> retune on 40m, it would stick at a 25.4:1 SWR. >>>> Tried switching down to 20m and it retuned right away to a 1.3:1. Applying >>>> external power to the unit, I tried tuning again on 40m (battery was >>>> reporting 10V if I recall correctly); It then tuned the end fed up, but >>>> only to a 1.7, which it will typically match to a 1.0:1, it would also get >>>> stuck at the 25.4:1 SWR on some of the attempted tunes. >>> ______________________________________________________________ >>> 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]
