More actual use testing. Charging at 1a.
All the batteries charged up good this time. 4.2 volts on the Keeppower.
Charged a mixed bag of older LSD NiMH. After charging with the UC put them in the XTAR.
But the USB power supply was weak so pulled one out then did one that after.
It's was actually ok as they were not in the XTAR for more than 15 minutes or so before being fully charged.
So from that powerbank it did just fine. But then from an Anker 3200 it cut short at 4 volts (remember the solar cut short at 4.1). I suppose that's better than not terminating the charge but no expert on this topic. It's a PITA to charge in a wall outlet (but did totally work) as the cord is so short and it has gotta, sorta hang unless using the USB ports on my power stripe. So this IMHO is a mobile thing. Which still makes me wonder why the powerbank inconstancy? I tested it with a larger Anker, 13000 mAh and it seemed to work fully but didn't write anything down or really double check it. Going to test some more with a few more powerbanks. Overall my advice is to test it with whatever power supply first before depending on it. I was really surprised the F1 didn't work to charge lithium ion yet seemed to work with NiMH when using the UC. I gotta revisit that. Given the light weight and bulk will probably pack it to support my camera, takes AA and headlamps AA/18650/14500 using a compatible power bank. Still don't get why they all don't work.