On 09/03/2014 03:17 AM, Kurt Pawlikowski wrote: > Josh, > > Unfortunately, I'm not familiar enough with the KXPA100 to know if, > when bypassing the unit internally, there is DC continuity between the > input and output. If there is (I suspect so), you should be able to > measure between them with a regular ohm meter. While not 100% > definitive, if it fails this test (again, assuming DC continuity), that > would be a major indicator of some connection problem.
Good advice. I used a multimeter to measure for continuity. Yikes, the tip and the ring of my "RX IN" jack appear to be shorted to each other, and also shorted to ground! Is that normal? I'm going to open it up and check the wires carefully on the panel where the jacks are, hopefully nothing is touching. I've heard that measuring antenna stuff at DC can be an illusion, as some things are supposed to appear open or appear shorted at DC, as they're designed to carry RF, not DC. My meter can only measure resistance at DC, it can't do anything fancier (no capacitance or inductance, no measuring resistance at AC/RF, no impedance or reactance). Also, when the antenna is selected, the tip and the ring of "ANT 1" (or "ANT 2" if selected) also appear to be shorted to each other and to ground. The KXPA100 isolates the antenna that is *not* selected: its ring is still shorted to ground, but its tip has no connection. Josh K6JSH > > Hope that helps! > > > kurtt WB9FMC > 2015 Hamfesters Hamfest Chairman > Looking for my replacement since 2014! > http:\\ham-ham.org > > On 9/3/2014 03:24, Josh Lehan wrote: >> Hi there! >> >> I assembled my KXPA100 (with ATU) recently, serial number 0595. >> Unfortunately, it isn't working. The link to the KX3 works great >> (rather slick, everything was instantly recognized), but the KXPA100 is >> not making any antenna connection cleanly. KX3 is properly configured >> to link with the KXPA100. >> >> I heard nothing at all, on any band, as if the antenna wasn't connected >> at all. I tried initiating an ATU tuning cycle, only to see a SWR fault >> on the KXPA100 almost instantly, so I stopped that rather quickly. The >> SWR wouldn't improve below 32.0-1 (terrible). >> >> I opened it up again and removed then reconnected the tricky little TMP >> connectors, and that helped a little. Using needlenose pliers made all >> the difference. I am now pretty confident I have the TMP connectors >> fully inserted (they weren't, earlier). Now, I can hear stations very >> faintly, S0 at most (not enough to light up any signal bars on the KX3). >> This is still very bad, because when bypassing the KXPA100 by using a >> barrel connector to connect the KX3 to the antenna directly (for >> testing), it's loud and clear, around S5-S9, which is normal for my >> antenna. >> >> I can transmit just fine, using the KX3 and its built-in ATU, without >> the KXPA100, so I can rule out anything else in my setup that might be >> causing a problem. Both antenna and dummy load normally work great. >> Ruled out cables by using barrel connector to join two cables together >> directly (cutting the KXPA100 out of the circuit) and that also worked >> great. I just can't get a good connection when going through the >> KXPA100. >> >> Now, I'm at a loss what to do. I think there might be a fault with the >> ATU connection internally of the KXPA100. It was straightforward to put >> it together, though, I don't think I made any mistakes there, but >> probably will disassemble it all and try again. >> >> Switching between antenna 1 and antenna 2 makes an audible difference in >> the noise level, so I know that works. However, the ATU switch on the >> KXPA100 doesn't seem to make a difference at all, there is no difference >> in noise level between bypass/manual/auto. Shouldn't there be an >> audible difference here? There also is no difference when KXPA100 is >> powered off vs. on, which seems strange to me. Same SWR fault happens >> instantly when trying to tune with ATU, or doing any transmission for >> that matter. >> >> What should be my next step in troubleshooting? >> >> Thanks! >> >> Josh >> K6JSH >> ______________________________________________________________ >> 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 ku...@pinrod.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
