How to calculate the size solar panel(s) required to charge radio batteries ?
Application: Portable/backpack radio & battery recharged via solar panel:
12V, 12Ahr Lithium Iron Battery provide power to Yaesu FT817ND or FT857D
Motorola PMNN4077C 7.4V, 2200mAh Battery in Moto XPR6550 hand-held
Charging using the 110vac wall-wort takes several hours, seeking the correct wattage of multiple small or larger roll-up solar panels to adequately recharge the radio batteries.