Many thanks to Ken (K6MR), Joe (4X1RV), and Kirk (K6KAR) for your quick answers and for providing the schematic information. I pulled the unit and did some poke and prod testing with a DVM here on the anti-static mat. My fear was that K18 had a bad contact in the ANT1 position. -Not!- What had apparently happened was that I had a batch of the offshore made "Amazon Special" PL-259s that appear to have a slightly oversize center pin. The patch cable used until recently had one of them on one end. It had spread the leaves on the ANT1 SO259 just enough that a good connector, when perfectly centered and seated, did not make contact! Gentle recentering of the leaves with a miniature flat blade screw drive yielded relief and a self-administered head smack. Jack Spitznagel - KD4IZ Science River LLC Biomedical Consulting Services
-----Original Message----- From: kirk.hard...@k6kar.com <kirk.hard...@k6kar.com> Sent: Sunday, July 11, 2021 14:07 To: kd...@frawg.org Subject: RE: [Elecraft] KAT500 ANT1 problem Jack, The KAT500 schematic is on line (partial) https://www.qsl.net/wb4kdi/Elecraft/KAT500/KAT500_RevA_page1.png https://www.qsl.net/wb4kdi/Elecraft/KAT500/KAT500_RevA_page2.png https://www.qsl.net/wb4kdi/Elecraft/KAT500/KAT500_RevA_page5.png Although all schematics aren't available, this may be enough to get you going. 73, Kirk, K6KAR -----Original Message----- From: elecraft-boun...@mailman.qth.net <elecraft-boun...@mailman.qth.net> On Behalf Of kd...@frawg.org Sent: Sunday, July 11, 2021 12:38 PM To: Elecraft@mailman.qth.net Cc: 'Elecraft Support' <supp...@elecraft.com> Subject: [Elecraft] KAT500 ANT1 problem All, This is likely something very straight forward, but I do not have a schematic to follow and troubleshoot. Symptom: ANT 1 circuit seems to be dead. No match and fault on switch from ANT2 to ANT1. No receive signal. Tests: Took KAT500 out of line to by-pass tuner, antenna on ANT1 is OK and will match normally with rig's internal ATU. With KAT500 back in line, selected each tuning position (AUTO, MAN, BYP) no difference With KAT500 still in line, ANT2 and ANT3 work nominally. Checks: Reset to factory defaults, restored last working Configuration, no change in above behavior. If I was a betting guy, I'd guess a relay or switching diode was open, however - no schematic, don't really know. Did I miss something Does this little beastie need to go back to the mothership? Thanks, Jack Spitznagel - KD4IZ Science River LLC Biomedical Consulting Services ______________________________________________________________ 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 kirk.hard...@k6kar.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