When we’re out and about I always have the KX3 and stuff with me. I leave the PX3 at home though. I power it all with a home built 10Ah LiFePo4 battery which gives me quite a while at 50W from my KXPA100.
Antenna is usually a doublet of about 50 feet / leg and fed with 300 ohm TV antenna twin lead. Needless to say some sort of impedance matching is required so I use a home brew Z-match ATU. The centre of the doublet is at around twenty feet on a squid pole.
Sometimes I use a 53 foot wire which is end fed via a 9:1 unun with about 20 or 25 feet of counterpoise. I prefer the doublet though. Another antenna I use a bit is 50 feet of zip cord with one conductor stripped off at 35 feet. Both antennas work pretty well for what they are just heaved into a tree if there’s one available. No trees ? I use the doublet.
One of my projects (apart from all the others) is to get a Pi 3 together for FT-8 and PSK and logging and do some really compact portable digital stuff – the thought of lugging a laptop and associated stuff around just doesn’t apeal.