I've solved my mystery. I read in the archives that the KAT3 ATU is not completely out of circuit in "bypass mode". If I understand correctly, small values of L and C are used to remove it functionally, but there is stray reactance that might contribute to the higher indicated SWR on some bands.
So then I wondered if the KAT3 might need to be tuned at least once into a 50 ohm load for the "bypass" state to be correctly determined. Made sense in my imagination, and thinking on it, I realised I'd never tuned the ATU into a 50 ohm load before. So I did that - tuned the KAT3 to the dummy load on the bands where it previously indicated higher than expected in ATU bypass mode. I let it do its stuff and find a match for the dummy load, then bypassed the ATU. Now, in ATU "Bypass" mode, the K3 reads 1.0:1 SWR into the same dummy load that it previously showed as 1.5:1. Issue gone. 73, John VK7JB -- View this message in context: http://elecraft.365791.n2.nabble.com/K3-SWR-meter-readings-on-10m-tp6519425p6520233.html Sent from the Elecraft mailing list archive at Nabble.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
