Rule out or in the feed line. Put the amp into a dummy load and see if it trips. Good Luck.
73/Gary W2CS > On May 31, 2020, at 12:54 PM, Jim Miller <[email protected]> wrote: > > I run 1500w for JT65 EME. No problems. My antenna measures 1.4:1 on the > KPA1500 swr meter and therefore never engages ATU. > > Have you vetted your feedline at 1500w? Many times something might be good > at low power and fail at 1500. neither the AA230 or K3s will stress such a > feedline. > > I believe the AA230 will do TDR. What does that show? Have you inspected > each connector for corrosion? > > jim ab3cv > > On Sun, May 31, 2020 at 12:47 PM Peter Dougherty <[email protected] > <mailto:[email protected]>> wrote: > >> Hi all (and sorry about the blank post-I don't know what happened there). >> >> >> >> I am experiencing a continuing and repeatable problem with my KPA-1500 on >> 6m. With the amp in bypass I am able to operate normally with my K3s, but >> the amp's meter is showing a 1.8 to 2:1 SWR on that band, despite >> measurements on an AA-230 analyzer and the SWR meter on the K3s itself >> showing it virtually flat (no more than 1.2:1). >> >> Once the amp is placed set to operate it's still showing SWR measurements >> of >> 1.8:1 to 2.1:1 consistently when delivering power. If the tuner is bypassed >> I can't run more than about 600W out before it faults. If I put the tuner >> in >> and click it to tune, it will deliver power just fine at 1200 or 1300 Watts >> for ONE FT8 transmit cycle. When it goes to transmit again it hard-faults >> with too much reflected power. Using 100W straight from the K3s there is no >> issue whatsoever, but *any* level of power from the KPA is liable to trip >> the excess reflected power sensor on the amp. >> >> At first I thought I had an antenna problem, but yesterday I put up a brand >> new 6m LFA and it's doing the same thing. This coming week I plan to >> replace >> the feedline with LMR-400--it's got a combination of 3/8" hardline and >> RG-213 at the moment. Any thoughts on what might be going on here? Is there >> a known-issue on 6m with the KPA? >> >> >> --------------------------------------------- >> 73 and Good DX >> Peter, W2IRT >> >> >> >> President, North Jersey DX Association >> >> DXCC Card Checker >> Letter O Manager, ARRL Incoming 2nd District QSL bureau >> >> >> >> ______________________________________________________________ >> 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] <mailto:[email protected]> >> > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > <http://mailman.qth.net/mailman/listinfo/elecraft> > Help: http://mailman.qth.net/mmfaq.htm <http://mailman.qth.net/mmfaq.htm> > Post: mailto:[email protected] <mailto:[email protected]> > > This list hosted by: http://www.qsl.net <http://www.qsl.net/> > Please help support this email list: http://www.qsl.net/donate.html > <http://www.qsl.net/donate.html> > Message delivered to [email protected] <mailto:[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]
