For some time I've been puzzled that, when doing a TX gain calibration either manually or with the utility, the SWR displayed was 1.0:1 on all bands except for 10m where it was 1.5:1. Yesterday my K3 (Ser. No. 266) had a meeting with a K3 (slightly earlier Ser. No.) belonging to David G4DMP (the owners met too!) and we found that his K3 was the same.
Now here's the interesting thing. During tx gain calibration a 50 ohm dummy load is used and the ATU is in bypass mode. As an experiment David put his K3's ATU in circuit on 10m and pressed ATU Tune - result (unsurprisingly) 1.0:1. He then put the ATU back into bypass mode and held Tune as one would do in a tx gain calibration. Hey presto - 1.0:1! My K3 behaved in exactly the same way and now always displays 1.0:1 on 10m into the dummy load with the ATU in bypass mode. Presumably this is something to do with the ATU not being out of circuit when in bypass mode. 73 to all Geoff G3UCK ______________________________________________________________ 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
