Thanks for all the calls today.
The antenna was a 21m long half wave end fed vertical held up by a Cody box kite. No advantage at this time of year, but its fun and much lighter than a fishing pole.
The DC power was supplied by a 5ah LiPo battery pack, which happily ran the IC7000 at full 100w+ output for the duration of the activation.
The LiPo pack is 600g, so its a lot lighter than equivalent SLABs. However it does require some voltage reduction, as the peak charged voltage is approx 16.8v. I do this with some bridge rectifier diodes in series and gradually remove them as the voltage drops. (Does anyone knows how to design light weight DC-DC converters that can handle 20A ?)
Overall its a nice combination if the wind is consistent.