I have similar issue and was told in this mailing list that the issue came from antenna port isolation but it was within specification. If you open the KAT500 box, you will find that lines between antenna ports and switch relay are close enough to cause inter-port cross-talk.
I wanted to switch 3 antennas with KAT500 but decided not. instead, I connected antenna 1 to port A, dummy load to port B and antenna 2 to power C. This improves isolation between antenna 1 and 2. 73 de JH3SIF, Keith Kiichiro (Keith) Onishi Sent from iPad 2018/07/08 7:08、Fred Jensen <k6...@foothill.net> のメッセージ: > Andy, > > From your explanation, it sounds like you've switched the active KAT500 > antenna port to a dummy load on which you're hearing a local 6m station. If > that's correct, I don't believe you're looking at port isolation, you're just > receiving a local guy on your dummy load, which wouldn't be at all strange. > What did I misunderstand here? > > 73, > > Fred ["Skip"] K6DGW > Sparks NV DM09dn > Washoe County > >> On 7/7/2018 12:27 PM, hawley, charles j jr wrote: >> If you have ever disassembled an alpha delta, you can see what it takes for >> an attempt at isolation. >> >> Chuck Jack >> KE9UW >> >> Sent from my iPhone, cjack >> >>> On Jul 7, 2018, at 2:13 PM, ANDY DURBIN <a.dur...@msn.com> wrote: >>> >>> I've been using Alpha Delta model Delta-4 switches for manual antenna >>> selection. I thought that having the ability to auto select the >>> appropriate antenna with my KAT500 would be a significant improvement for >>> my station. I don't have a K3 so I created a band decoder that drives the >>> KAT500 band inputs and now have automatic antenna switching. However, I'm >>> unimpressed by the isolation between antenna ports. >>> >>> With the KAT500 switched to the dummy load I'm still decoding a local FT8 >>> station on 6 m. The difference in the FT8 signal between dummy load and >>> antenna is about 19 dB. I have not found a specification for KAT500 port >>> isolation. Is what I'm seeing typical? >>> >>> Thanks and 73, >>> Andy k3wyc >>> > > ______________________________________________________________ > 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 jh3...@sumaq.jp ______________________________________________________________ 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
