I have gone and done it now. Got out the laptop and a couple of cables and after waiting for forever while windows crashed and updated and was just a typical pain in the arse, I finally got it all working and with a flat battery and only putting out about 10w, made a single contact into the USA with NT9J as proof its working on the 15m band.
I only called CQ 4 times and worked the one station before putting the battery on the charger to top it back up. Next I will have to find where the power supply is and get it out and use it. I have power out in the sun room so its no problems to hook up, its just cold out there at night and on days like today when its overcast and raining.
One thing I know is, once i have some better antennas in the air, I should be able to do quite ok from here. No noise floor means I hear everything and I know that I am already putting out a better signal than i did at the old house. I would never have been spotted in the EU this early in the day and certainly not with the 30w i typically run on FT8, let alone the 10w im currently doing.
Its looking promising.
EDIT: Gave the battery 30mins on charger and had another go. Antenna seems to favor the USA, going to have to change its orientation and try again tomorrow and see if things are different. I do not think i have ever seen so many spots in the USA on 15m. Its a bit early for all the action on 40m. But the spot in Chile is promising.