Specifically methylates the guanine in position 1207 of 16S rRNA in the 30S particle. guanosine(1207) in 16S rRNA + S-adenosyl-L-methionine = H(+) + N(2)-methylguanosine(1207) in 16S rRNA + S-adenosyl-L-homocysteine Monomer. Belongs to the methyltransferase superfamily. RsmC family.