Default [Q] SPH-L720 need help with mdoem

hi new to posting if i am not in the right area just move my thread

hi im running gummy rom 1.1 (release date 11-21-13) and i have L720VPUEMK2 as my baseband
but im having signal drops no LTE or 3g so what is the best modem to use with this rom

NEED HELP ASAP