Stupid system.....logged me out while I was typing....OK, shorter version: there is a 'pulsating' noise and visual (on Mic Stream on the DAX) when transmitting on FT8, 20 m. Rig is a 6300, V 2.1.33. Was working fine for a while, just noticed this as replies to contacts dropped off. OK, further info: seems to be an ATU issue. With the ATU turned off, the pulsing stops BUT the SWRs go up to about 1.7 or a bit higher. SWR has never been an issue with the TransWorld antenna, better go see if it has ants!