/P-ish second attempt
Success. After my failed first attempt I untangled all the leads, ditched the USB hub and tried a 1:1 unun. With the FT818 set to 2.5W I managed a QSO with a DK at about -13. The wifi was struggling for the Mac to load pskreporter so had to try that once back in the house, but it shows it is getting out ok. Not too bad for 2.5W into a Diamond HF40CL on the car roof parked next to the house. Hopefully this bodes well for an excursion and possible attempt at activating a POTA.
No ferrites on the antenna lead plus one on each USB lead. I did not take those off to experiment as they are not in the way anyway.